文章
Dummer. ゛☀
2017年09月19日
Dischidia is a genus of some 80 species of trailing, twining or scandent, succulent epiphytes found throughout the tropics of Asia (New Guinea, Moluccas, Philippines, India, tropical Australia, Hong Kong, Taiwan) through to the western Pacific.
Dischidia are plants that grow on supports such as tree trunks or branches. Their stems may produce roots along the nodes to absorb nutrients and water and provide additional support for the plant. Dischidia are some of the easiest and most rewarding plants to grow! They tolerate wide variations in temperature and humidity. A very succulent species with grey/yellow/green colored foliage depending on light exposure. The foliage is also somewhat variable depending upon culture. A quick grower for drier areas of the terrarium and excellent in hanging baskets for home and garden!
Growing Conditions
Light: Grow Dischidia in medium to bright light to keep the plant happy.
Water: Water Dischidia when the soil surface starts to dry. The plant is fairly drought tolerant, so you don’t need to be alarmed if you forget to water it now and again.
USDA Hardiness Zone: 10 and 11.
Soil: Plant your Dischidia in a loose, well-draining soil designed for epiphytic plants; it is usually composed of coconut husk or shredded bark.
Grower’s Tips
Allow the soil to dry out before you water the plant. They are used to getting moisture only from dew and the air, and cannot tolerate boggy media. When the bark medium is dry to the touch, submerge the container in water until air bubbles are gone.
Dischidia also needs high humidity. Mist the plant every day or place the container on a saucer filled with pebbles and water. The water will evaporate and moisten the air while the pebbles will hold the sensitive roots out of the water.
Dischidia doesn’t really need fertilizer but you should change the planting media every year. If you wish, apply a diluted by half liquid plant food when you water beginning in spring and stopping by September.
Dischidia are plants that grow on supports such as tree trunks or branches. Their stems may produce roots along the nodes to absorb nutrients and water and provide additional support for the plant. Dischidia are some of the easiest and most rewarding plants to grow! They tolerate wide variations in temperature and humidity. A very succulent species with grey/yellow/green colored foliage depending on light exposure. The foliage is also somewhat variable depending upon culture. A quick grower for drier areas of the terrarium and excellent in hanging baskets for home and garden!
Growing Conditions
Light: Grow Dischidia in medium to bright light to keep the plant happy.
Water: Water Dischidia when the soil surface starts to dry. The plant is fairly drought tolerant, so you don’t need to be alarmed if you forget to water it now and again.
USDA Hardiness Zone: 10 and 11.
Soil: Plant your Dischidia in a loose, well-draining soil designed for epiphytic plants; it is usually composed of coconut husk or shredded bark.
Grower’s Tips
Allow the soil to dry out before you water the plant. They are used to getting moisture only from dew and the air, and cannot tolerate boggy media. When the bark medium is dry to the touch, submerge the container in water until air bubbles are gone.
Dischidia also needs high humidity. Mist the plant every day or place the container on a saucer filled with pebbles and water. The water will evaporate and moisten the air while the pebbles will hold the sensitive roots out of the water.
Dischidia doesn’t really need fertilizer but you should change the planting media every year. If you wish, apply a diluted by half liquid plant food when you water beginning in spring and stopping by September.
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文章
Dummer. ゛☀
2017年09月19日
Frailea are very small cacti that rarely reach 2 inches (5 cm) in diameter. The plants are native Brazil. These little cacti are quite interesting in their form but their life cycle is even more surprising. There are several species of this genus available for home growers, but the plants are considered threatened in their native habitat.
Rounded, flattish mounds of solitary to occasionally divided chocolate, purple-brown or greenish brown Fraileas make interesting contrasts to other succulents. This genus is named for Manuel Fraile, who once was in charge of the cactus collection of the United States Department of Agriculture.
Growing Fraileas is not difficult and these little plants are super starter plants for the novice gardener or just for someone who travels consistently but wants to come home to a living thing.
The majority of these plants grow as solitary little flattened domes. The spines are extremely tiny and arrayed along the ribs. The body of the plant may range from chocolate to reddish green with several other color variations possible. Often, the plant will produce a fuzzy white fruit that dries to a fragile, membranous capsule filled with large seeds. This fruit is often a surprise as flowers are rare and are cleistogamous, meaning they don’t need to open to produce fruit and seed.
If you are lucky enough to observe a full bloom, the flower will be larger than the body of the plant and rich sulfur yellow. Growing Frailea is easy from seed as germination is quick and reliable.
Rounded, flattish mounds of solitary to occasionally divided chocolate, purple-brown or greenish brown Fraileas make interesting contrasts to other succulents. This genus is named for Manuel Fraile, who once was in charge of the cactus collection of the United States Department of Agriculture.
Growing Fraileas is not difficult and these little plants are super starter plants for the novice gardener or just for someone who travels consistently but wants to come home to a living thing.
The majority of these plants grow as solitary little flattened domes. The spines are extremely tiny and arrayed along the ribs. The body of the plant may range from chocolate to reddish green with several other color variations possible. Often, the plant will produce a fuzzy white fruit that dries to a fragile, membranous capsule filled with large seeds. This fruit is often a surprise as flowers are rare and are cleistogamous, meaning they don’t need to open to produce fruit and seed.
If you are lucky enough to observe a full bloom, the flower will be larger than the body of the plant and rich sulfur yellow. Growing Frailea is easy from seed as germination is quick and reliable.
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文章
Dummer. ゛☀
2017年09月19日
A major agricultural pest, the tomato fruitworm can feed on many different plants. Hence, the species has been given many different common names including cotton bollworm and corn earworm. It has also been known to consume tobacco, legumes, grain sorghum, and other vegetables and fruits.
The pest occurs throughout the Western Hemisphere. In warm areas several generations occur annually. North of Interstate 70 the pupae cannot overwinter in the soil. Most populations enter Missouri as migrating swarms of moths from the southern United States.
Symptoms and Diagnosis
Tomato Fruitworm
The evidence of tomato fruitworm is usually a visible black hole at the base of the fruit stem. When the tomato is cut, tunneling is evident and the cavity may contain frass and decay as well as the worm itself.
Corn Earworm
Most evidence of corn earworm is at the tip of the ear—damaged kernels, frass, the worm itself, and possibly resulting fungal disease.
Life Cycle
The eggs of this pest are each about ½ the diameter of a pinhead. They are spherical with a flattened base and white or cream in color, developing a reddish-brown band just prior to the young hatching. Depending on the temperature, the young hatch in 2-10 days.
The larvae measure 11/2-2 inches when fully grown and may be green, brown, pink, yellow, or even black. They have tan heads and alternating light and dark stripes run lengthwise on the bodies. The skin is coarse and has small, thorn-like projections called tubercles. The larval stage lasts 14-21 days.
When the larvae are finished feeding the worms drop to the ground and enter the soil near the base of the plant where they transform into shiny brown pupae. During summer adults emerge in 10-14 days and start the cycle over. In the fall, south of Interstate 70 the pupae survive winter 2-6 inches below the soil surface. The moths emerge from overwintering pupae during late April and May.
Adult moths are usually light yellow-olive in color with a single dark spot near the center of each forewing. Each forewing has 3 slanted dark bands. Their hind wings are white.
The cycle repeats itself with the moths laying eggs at dusk on host plants on warm days. The total generation time is 28-35 days.
The moths lay eggs on the foliage of the tomato plants. With corn the moths usually lay eggs on corn tassels and silks but the larvae will migrate down the silk to the ear tips within one hour of hatching where they will feed on the developing kernels protected by the husk. When larval development is complete the larvae chew through the husk and drop to the ground to begin the pupal stage.
Integrated Pest Management Strategies
Tomato Fruitworm
1. Sanitation. Collect and dispose of any infested fruit before the insect completes its life cycle.
2. Introduce parasitic wasps. Do not remove parasitized caterpillars. Instead, leave them to assist as a natural, biological control.
3. Dusting with diatomaceous earth may kill larvae.
4. Use of a biological pesticide such as Bt can kill larvae during the warmest months.
5. Use chemical pesticides. The pest has developed a resistance to many pesticides but the following pesticides are often used: esfenvalerate (Asana), methomyl (Lannate), azinphos-methyl (Guthion), carbaryl (Sevin), or pyrethrin. These must be applied before the worm enters the fruit.
6. Minimize local food sources. Avoid planting tomatoes near corn or other hosts of the fruitworm to minimize populations.
The pest occurs throughout the Western Hemisphere. In warm areas several generations occur annually. North of Interstate 70 the pupae cannot overwinter in the soil. Most populations enter Missouri as migrating swarms of moths from the southern United States.
Symptoms and Diagnosis
Tomato Fruitworm
The evidence of tomato fruitworm is usually a visible black hole at the base of the fruit stem. When the tomato is cut, tunneling is evident and the cavity may contain frass and decay as well as the worm itself.
Corn Earworm
Most evidence of corn earworm is at the tip of the ear—damaged kernels, frass, the worm itself, and possibly resulting fungal disease.
Life Cycle
The eggs of this pest are each about ½ the diameter of a pinhead. They are spherical with a flattened base and white or cream in color, developing a reddish-brown band just prior to the young hatching. Depending on the temperature, the young hatch in 2-10 days.
The larvae measure 11/2-2 inches when fully grown and may be green, brown, pink, yellow, or even black. They have tan heads and alternating light and dark stripes run lengthwise on the bodies. The skin is coarse and has small, thorn-like projections called tubercles. The larval stage lasts 14-21 days.
When the larvae are finished feeding the worms drop to the ground and enter the soil near the base of the plant where they transform into shiny brown pupae. During summer adults emerge in 10-14 days and start the cycle over. In the fall, south of Interstate 70 the pupae survive winter 2-6 inches below the soil surface. The moths emerge from overwintering pupae during late April and May.
Adult moths are usually light yellow-olive in color with a single dark spot near the center of each forewing. Each forewing has 3 slanted dark bands. Their hind wings are white.
The cycle repeats itself with the moths laying eggs at dusk on host plants on warm days. The total generation time is 28-35 days.
The moths lay eggs on the foliage of the tomato plants. With corn the moths usually lay eggs on corn tassels and silks but the larvae will migrate down the silk to the ear tips within one hour of hatching where they will feed on the developing kernels protected by the husk. When larval development is complete the larvae chew through the husk and drop to the ground to begin the pupal stage.
Integrated Pest Management Strategies
Tomato Fruitworm
1. Sanitation. Collect and dispose of any infested fruit before the insect completes its life cycle.
2. Introduce parasitic wasps. Do not remove parasitized caterpillars. Instead, leave them to assist as a natural, biological control.
3. Dusting with diatomaceous earth may kill larvae.
4. Use of a biological pesticide such as Bt can kill larvae during the warmest months.
5. Use chemical pesticides. The pest has developed a resistance to many pesticides but the following pesticides are often used: esfenvalerate (Asana), methomyl (Lannate), azinphos-methyl (Guthion), carbaryl (Sevin), or pyrethrin. These must be applied before the worm enters the fruit.
6. Minimize local food sources. Avoid planting tomatoes near corn or other hosts of the fruitworm to minimize populations.
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文章
Dummer. ゛☀
2017年09月19日
Root-knot nematodes are microscopic, plant-parasitic roundworms in the genus, Meloidogyne. Normally they exist in sandy soil in hot climates or short winters, but they have spread to our region as well. In Missouri alone 40 species of parasitic nematodes exist. About 2000 plants are susceptible to infection by these nematodes, and they can cause global crop loss. Root-knot nematode larvae infect plant roots that drain the plant’s ability to take up water and sufficient nutrients. Because of their microscopic size the nematodes go unnoticed until serious symptoms appear. The pathogenic nematodes can allow entrances for root rots, and wilts. They can also transmit viral diseases.
Symptoms and Diagnosis
A plant infected with root-knot nematodes often exhibits the same signs of nutrient deficiency. It may be stunted, yellowed, or wilted, and can lead to premature death of the plant. Below the ground, the roots of the plant are swollen or knotted with root galls, and unless a plant is removed from the soil to examine the roots, the cause of the poor plant growth remains undetected. The appearance of the galls on the roots can be confused with nitrogen-fixing nodules common in the legume family. However it is easy to distinguish between them, as the nitrogen nodules can be easily rubbed off while the nematode galls cannot be removed.
Life Cycle
The root-knot nematode is parthenogenic, that is a single female can reproduce without males and a new generation can occur every 28 days if conditions are ideal. Inside the gall, the enlarged female appears as a shiny white body, the size of a pinhead. She deposits 300 to 500 eggs in a protective jelly-like material. These glistening white to yellow egg masses are present on the root surfaces. Juveniles emerge from the eggs in the soil and penetrate between and through cells at the center of the root, usually near the growing tip. These larvae actively feed and remain at this same site. The juvenile stage can over-winter even under very unfavorable conditions. New adult nematodes develop from the larvae and start the cycle again.
Integrated Pest Management Strategies
1. Never buy or plant any stunted-yellowed plants. When a new plant’s roots are examined and its roots contain root knots that will not easily rub off, do not plant it. If someone gives you a division of their plant whose roots contain these root-knots, never add it to your garden because it will contaminate all of your healthy plants with the nematodes.
2. Keep plants healthy and avoid stressing plants and water plants during periods of high temperatures and drought. Also keep other insect pests and fungal diseases under control. Control weeds as they can act as hosts to these nematodes. Keep tools clean.
3. ;Rotate crops, planting nematode resistant plants when possible. It may take 3-5 years to kill off these nematodes before replanting the same plant.
4. Destroy any plants you discover that are infested with root-knot nematodes and don’t compost them. Replace all the soil before adding a new plant to this area.
5. Soil solarization has demonstrated some success in eliminating root-knot nematodes. Thoroughly moisten the soil and cover with clear plastic in full sun during the hottest months of the year. The soil must maintain these high temperatures for a period of at least 4-6 weeks to be effective. Re-moisten the soil under the plastic if it dries out.
6. No chemical controls are advised for home gardeners. Some restricted use chemicals are available for commercial, licensed applicators.
Symptoms and Diagnosis
A plant infected with root-knot nematodes often exhibits the same signs of nutrient deficiency. It may be stunted, yellowed, or wilted, and can lead to premature death of the plant. Below the ground, the roots of the plant are swollen or knotted with root galls, and unless a plant is removed from the soil to examine the roots, the cause of the poor plant growth remains undetected. The appearance of the galls on the roots can be confused with nitrogen-fixing nodules common in the legume family. However it is easy to distinguish between them, as the nitrogen nodules can be easily rubbed off while the nematode galls cannot be removed.
Life Cycle
The root-knot nematode is parthenogenic, that is a single female can reproduce without males and a new generation can occur every 28 days if conditions are ideal. Inside the gall, the enlarged female appears as a shiny white body, the size of a pinhead. She deposits 300 to 500 eggs in a protective jelly-like material. These glistening white to yellow egg masses are present on the root surfaces. Juveniles emerge from the eggs in the soil and penetrate between and through cells at the center of the root, usually near the growing tip. These larvae actively feed and remain at this same site. The juvenile stage can over-winter even under very unfavorable conditions. New adult nematodes develop from the larvae and start the cycle again.
Integrated Pest Management Strategies
1. Never buy or plant any stunted-yellowed plants. When a new plant’s roots are examined and its roots contain root knots that will not easily rub off, do not plant it. If someone gives you a division of their plant whose roots contain these root-knots, never add it to your garden because it will contaminate all of your healthy plants with the nematodes.
2. Keep plants healthy and avoid stressing plants and water plants during periods of high temperatures and drought. Also keep other insect pests and fungal diseases under control. Control weeds as they can act as hosts to these nematodes. Keep tools clean.
3. ;Rotate crops, planting nematode resistant plants when possible. It may take 3-5 years to kill off these nematodes before replanting the same plant.
4. Destroy any plants you discover that are infested with root-knot nematodes and don’t compost them. Replace all the soil before adding a new plant to this area.
5. Soil solarization has demonstrated some success in eliminating root-knot nematodes. Thoroughly moisten the soil and cover with clear plastic in full sun during the hottest months of the year. The soil must maintain these high temperatures for a period of at least 4-6 weeks to be effective. Re-moisten the soil under the plastic if it dries out.
6. No chemical controls are advised for home gardeners. Some restricted use chemicals are available for commercial, licensed applicators.
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文章
Dummer. ゛☀
2017年09月19日
Oak leaf blister (oak leaf curl) is a fungal leaf disease caused by the fungus Taphrina caerulescens. Circular, raised areas ranging up to 2 inches in diameter are scattered over the upper leaf surface. During cool wet springs, almost all species of oak are subject to the leaf blister disease. Members of the red oak family are particularly susceptible to infection. The disease is closely related to Taprina deformans which causes peach leaf curl.
Symptoms and Diagnosis
Blister-like, circular, raised areas appear scattered on the upper leaf surface. This raised area causes a corresponding depression on the lower leaf surface at the same site and of the same size. The color of the upper convex area is yellowish white while the bottom concave area is yellowish brown.
Leaves with numerous spots may fall prematurely to the ground. If well-established trees defoliate before midsummer, they will sometimes leaf out later in the season. When defoliation occurs in late summer, leaf loss will have little impact on the overall health of the tree.
Life Cycle
During mid-spring, microscopic spores are produced in leaf spots. These spores are carried by wind and splashing raindrops onto bud scales and twigs where they remain in a dormant stage until the following early spring. At this time, rain washes the spores onto young leaves where infection takes place. Depending on weather conditions, small circular spots begin to develop in 2 to 4 weeks. Spores produced on these spots will lodge in bud scales and again remain resting until the following spring. Cool wet weather is required for germination on young leaves, and if these conditions continue, severe infection can occur. If weather conditions are not favorable for spore germination shortly after bud break, only minor infection will occur. As the leaves mature, they become more resistant to infection.
Integrated Pest Management Strategies
1. Maintain plant vigor. Keep the tree well watered during drought conditions (approximately 1 inch of water per week) and well-drained during periods of heavy rain. Fertilize according to soil test recommendations. Apply nitrogen every 3 to 5 years for mature shade trees.
2. General health. Oak leaf blister does not seriously affect the overall health of the tree unless the tree is repeatedly defoliated in successive years. Even if this occurs, the second set of leaves should emerge at a time when conditions are not conducive to reinfection of leaves and newly formed bud scales.
3. Fungicides. A single application of a fungicide applied in the spring at the time of bud-swelling is usually adequate. Apply with a power sprayer and coat buds and twigs thoroughly for good control. chlorothalonil (Daconil) is currently registered for use in controlling oak leaf blister. Fungicides will not be effective if applied after bud break. As with the use of all chemicals, carefully read and follow the manufacturer’s directions.
Symptoms and Diagnosis
Blister-like, circular, raised areas appear scattered on the upper leaf surface. This raised area causes a corresponding depression on the lower leaf surface at the same site and of the same size. The color of the upper convex area is yellowish white while the bottom concave area is yellowish brown.
Leaves with numerous spots may fall prematurely to the ground. If well-established trees defoliate before midsummer, they will sometimes leaf out later in the season. When defoliation occurs in late summer, leaf loss will have little impact on the overall health of the tree.
Life Cycle
During mid-spring, microscopic spores are produced in leaf spots. These spores are carried by wind and splashing raindrops onto bud scales and twigs where they remain in a dormant stage until the following early spring. At this time, rain washes the spores onto young leaves where infection takes place. Depending on weather conditions, small circular spots begin to develop in 2 to 4 weeks. Spores produced on these spots will lodge in bud scales and again remain resting until the following spring. Cool wet weather is required for germination on young leaves, and if these conditions continue, severe infection can occur. If weather conditions are not favorable for spore germination shortly after bud break, only minor infection will occur. As the leaves mature, they become more resistant to infection.
Integrated Pest Management Strategies
1. Maintain plant vigor. Keep the tree well watered during drought conditions (approximately 1 inch of water per week) and well-drained during periods of heavy rain. Fertilize according to soil test recommendations. Apply nitrogen every 3 to 5 years for mature shade trees.
2. General health. Oak leaf blister does not seriously affect the overall health of the tree unless the tree is repeatedly defoliated in successive years. Even if this occurs, the second set of leaves should emerge at a time when conditions are not conducive to reinfection of leaves and newly formed bud scales.
3. Fungicides. A single application of a fungicide applied in the spring at the time of bud-swelling is usually adequate. Apply with a power sprayer and coat buds and twigs thoroughly for good control. chlorothalonil (Daconil) is currently registered for use in controlling oak leaf blister. Fungicides will not be effective if applied after bud break. As with the use of all chemicals, carefully read and follow the manufacturer’s directions.
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文章
Dummer. ゛☀
2017年09月19日
Worldwide, Nectria fungi cause several common canker and dieback diseases, especially in hardwood trees. Nectria canker, which is caused by the fungus, Nectria galligena, may occur on over 60 species of trees and shrubs including apple, ash, birch, dogwood, elm, sweet gum, holly, maple, pear and walnut. A similar disease infects members of the magnolia family. Nectria canker is usually not a fatal disease, but it can cause considerable damage as the cankered area is weakened and susceptible to breakage. It may also adversely affect the appearance of the affected plant. This disease is important commercially as it reduces the quality and quantity of forest products.
Another member of the Nectria genus, Nectria cinnabarina, causes the disease Nectria dieback. Also known as coral spot Nectria canker or Nectria canker, this disease occurs on many plant species, including apple, ash, barberry, birch, boxwood, crabapple, elm, hickory, honey locust, linden, maple, pear, rose and Japanese zelkova. Nectria cinnabarina usually grows as a saprophyte on dead wood, but if a plant is wounded or otherwise stressed, the fungus becomes an opportunistic weak parasite, producing cankers and causing dieback of twigs and branches. Maples are especially affected by this disease as are recently wounded or severely pruned trees and shrubs, urban ornamentals and new transplants of other species.
Symptoms and Diagnosis
Although it is most common in spring and fall, the Nectria fungus can infect plants throughout the year as long as there is sufficient moisture and the temperature is above freezing. Plants that are stressed by cold, drought, mechanical injuries or other disease are especially susceptible. Infections may be worse in autumn and winter when the host plant is dormant and wound recovery is weaker than in the growing season.
The first symptom of a Nectria infection is a depressed discolored area of bark near wounds or at the base of dead twigs or branches. These cankers are usually not noticed until other symptoms appear.
The first easily visible signs of Nectria canker are small creamy white or red to reddish orange fruiting structures and the development of callus tissue. This callus tissue is produced as the host plant attempts to isolate the fungus. If the callus does not isolate the infection, the fungus will continue to grow into healthy wood and the plant will respond by growing another ridge of callus tissue. This alternation of fungal growth and callus ridge, which may occur for many years, results in a rounded or elongated target-like shape. The bark of older ridges may decay and weather away exposing the ridges of wood underneath. This disease grows slowly and larger stems are rarely girdled, although multiple lesions may grow together and kill a branch or the entire plant. Plants that are stressed are most severely affected by the disease. This fungus may also affect apple fruit causing it to rot during storage.
The first obvious sign of Nectria dieback may not occur until spring when the plant begins to grow. Affected twigs, branches, or even entire plants will not produce leaves or may wilt suddenly. Larger branches or small trees may be girdled and killed. The fungus produces reproductive structures that vary in color from creamy, coral pink, pink-orange, light purplish red or orange-red and that darken as they mature.
Life Cycle
Nectria galligena overwinters in the callus tissue growing slowly while its host is dormant. During moist periods, creamy white cushion-like fruiting structures will develop. These are followed by a second type of reproductive structure, which is red to reddish orange, pin-head sized and lemon-shaped, in autumn through spring. During rain or other moist weather, spores are released and dispersed by wind or water infecting susceptible plants through natural openings such as leaf scars or through wounds from improper pruning, sunscald, storm damage, frost cracks or other mechanical damage. As the fungus grows, it kills bark, cambium, and the outermost sapwood.
The life cycle of the Nectria dieback fungus is similar to that of Nectria canker. Creamy to coral pink to pink-orange or light purplish red spore-producing structures develop in spring or early summer. These will age to tan, brown, or nearly black. Orange-red fruiting structures, which mature to dark reddish brown and may persist through winter, are produced in summer and autumn. Both structures release spores that are dispersed by water and can invade susceptible tissue producing cankers and dieback.
Integrated Pest Management Strategies
1. Proper selection. Choose trees and shrubs that are well adapted to the climate of the area to minimize infection due to freeze damage and other environmental stresses.
2. Maintain plant vigor. Keep plants healthy and growing vigorously by using good cultural techniques. These include choosing the appropriate planting site, watering during dry periods, using mulch around the base of the tree or shrub and fertilizing and pruning properly. Pruning is best done in late winter. Avoid pruning in spring when higher moisture can increase risk of infection or in late summer and autumn, which can delay the plant’s natural cold hardiness response. Minimize any wounding due to root pruning, transplanting or lawnmowers to reduce infection sites.
3. Prune. Prune out branch cankers during dry periods when conditions are unfavorable for infection. Disinfect pruning tools in a 1-part bleach to 9-parts water solution between each cut.
Another member of the Nectria genus, Nectria cinnabarina, causes the disease Nectria dieback. Also known as coral spot Nectria canker or Nectria canker, this disease occurs on many plant species, including apple, ash, barberry, birch, boxwood, crabapple, elm, hickory, honey locust, linden, maple, pear, rose and Japanese zelkova. Nectria cinnabarina usually grows as a saprophyte on dead wood, but if a plant is wounded or otherwise stressed, the fungus becomes an opportunistic weak parasite, producing cankers and causing dieback of twigs and branches. Maples are especially affected by this disease as are recently wounded or severely pruned trees and shrubs, urban ornamentals and new transplants of other species.
Symptoms and Diagnosis
Although it is most common in spring and fall, the Nectria fungus can infect plants throughout the year as long as there is sufficient moisture and the temperature is above freezing. Plants that are stressed by cold, drought, mechanical injuries or other disease are especially susceptible. Infections may be worse in autumn and winter when the host plant is dormant and wound recovery is weaker than in the growing season.
The first symptom of a Nectria infection is a depressed discolored area of bark near wounds or at the base of dead twigs or branches. These cankers are usually not noticed until other symptoms appear.
The first easily visible signs of Nectria canker are small creamy white or red to reddish orange fruiting structures and the development of callus tissue. This callus tissue is produced as the host plant attempts to isolate the fungus. If the callus does not isolate the infection, the fungus will continue to grow into healthy wood and the plant will respond by growing another ridge of callus tissue. This alternation of fungal growth and callus ridge, which may occur for many years, results in a rounded or elongated target-like shape. The bark of older ridges may decay and weather away exposing the ridges of wood underneath. This disease grows slowly and larger stems are rarely girdled, although multiple lesions may grow together and kill a branch or the entire plant. Plants that are stressed are most severely affected by the disease. This fungus may also affect apple fruit causing it to rot during storage.
The first obvious sign of Nectria dieback may not occur until spring when the plant begins to grow. Affected twigs, branches, or even entire plants will not produce leaves or may wilt suddenly. Larger branches or small trees may be girdled and killed. The fungus produces reproductive structures that vary in color from creamy, coral pink, pink-orange, light purplish red or orange-red and that darken as they mature.
Life Cycle
Nectria galligena overwinters in the callus tissue growing slowly while its host is dormant. During moist periods, creamy white cushion-like fruiting structures will develop. These are followed by a second type of reproductive structure, which is red to reddish orange, pin-head sized and lemon-shaped, in autumn through spring. During rain or other moist weather, spores are released and dispersed by wind or water infecting susceptible plants through natural openings such as leaf scars or through wounds from improper pruning, sunscald, storm damage, frost cracks or other mechanical damage. As the fungus grows, it kills bark, cambium, and the outermost sapwood.
The life cycle of the Nectria dieback fungus is similar to that of Nectria canker. Creamy to coral pink to pink-orange or light purplish red spore-producing structures develop in spring or early summer. These will age to tan, brown, or nearly black. Orange-red fruiting structures, which mature to dark reddish brown and may persist through winter, are produced in summer and autumn. Both structures release spores that are dispersed by water and can invade susceptible tissue producing cankers and dieback.
Integrated Pest Management Strategies
1. Proper selection. Choose trees and shrubs that are well adapted to the climate of the area to minimize infection due to freeze damage and other environmental stresses.
2. Maintain plant vigor. Keep plants healthy and growing vigorously by using good cultural techniques. These include choosing the appropriate planting site, watering during dry periods, using mulch around the base of the tree or shrub and fertilizing and pruning properly. Pruning is best done in late winter. Avoid pruning in spring when higher moisture can increase risk of infection or in late summer and autumn, which can delay the plant’s natural cold hardiness response. Minimize any wounding due to root pruning, transplanting or lawnmowers to reduce infection sites.
3. Prune. Prune out branch cankers during dry periods when conditions are unfavorable for infection. Disinfect pruning tools in a 1-part bleach to 9-parts water solution between each cut.
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文章
Dummer. ゛☀
2017年09月19日
Cornus species are riddled with leaf diseases. After the discovery of dogwood anthracnose that devastated the dogwood population in the northeastern U.S., it has been increasingly more significant to be on alert for disease outbreaks. Three leaf spot diseases that show themselves in varying degrees are dogwood anthracnose, spot anthracnose, and powdery mildew. Dogwood anthracnose and powdery mildew are of particular concern. Dogwood anthracnose was confirmed in St. Louis in 2012 and again in 2015. Powdery mildew can occur yearly.
Symptoms and Diagnosis
Symptoms of Dogwood Anthracnose: Dogwood anthracnose is a disease caused by the fungus, Discula destructiva. Since its discovery in the 1970s, the spread has been swift and the results disastrous to the native Cornus florida. Symptoms include leaf spots that are soft and very wet with purple borders, twig blight, dead leaves that cling to the tree, epicormic shoots (water sprouts with many shoots occurring near the base of the tree), lower branch dieback, and eventually death. Conditions that favor disease include low light levels, high humidity, and temperatures of 60 F. In the St. Louis area it was found in the Kirkwood/Ladue area in 2012 and the Brentwood area in 2015. It is considered established in St. Louis.
Symptoms of Spot Anthracnose: Spot anthracnose is caused by the fungus, Elsinoe corni. Symptoms include small, dark, pinprick lesions with purple borders on leaf surfaces. The lesions are numerous and usually occur on dry leaves. The disease is unsightly, but typically not very harmful.
Symptoms of Powdery Mildew: Powdery mildew is caused by the fungus, Microsphaera pulchra. Early symptoms include round, white or gray powder-like spots that appear on upper leaf surfaces. These spots form a dry white layer on leaves. As young leaves become infected, they appear twisted, dry, and leathery. Older leaves look bronzed. Moderate temperatures, low light, and high humidity accelerate this disease. High nitrogen levels cause the disease to flourish.
Integrated Pest Management Strategies
1. Choose disease resistant varieties. A soon-to-be released cultivar for dogwood anthracnose resistance is called ‘Appalachian Spring’. Cultivars less susceptible to spot anthracnose include ‘Cherokee Princess’, ‘Cherokee Sunset’, and ‘Springtime’. ‘Cherokee Brave’, C. kousa, and C. kousa x C. florida crosses are resistant to powdery mildew.
2. Water the roots of the tree. Avoid using overhead irrigation in order to reduce the incidence of leaf spot.
3. Practice good sanitation. Promptly remove and dispose of any dead or dying twigs or branches found in trees as well as leaves that show the symptoms of dogwood anthracnose. Leaves with spot anthrancnose and powdery mildew can remain but rake and remove them in the fall when they drop.
4. Remove plants confirmed with dogwood anthracnose. Removing an infected tree confirmed with dogwood anthracnose is strongly recommended. The infected trees should NOT be converted to mulch to avoid spreading the disease.
5. Apply fungicides. If you suspect dogwood anthracnose, get it diagnosed by a professional prior to a fungicide application. Powdery mildew should also be controlled, especially if the disease has occurred previously.
Symptoms and Diagnosis
Symptoms of Dogwood Anthracnose: Dogwood anthracnose is a disease caused by the fungus, Discula destructiva. Since its discovery in the 1970s, the spread has been swift and the results disastrous to the native Cornus florida. Symptoms include leaf spots that are soft and very wet with purple borders, twig blight, dead leaves that cling to the tree, epicormic shoots (water sprouts with many shoots occurring near the base of the tree), lower branch dieback, and eventually death. Conditions that favor disease include low light levels, high humidity, and temperatures of 60 F. In the St. Louis area it was found in the Kirkwood/Ladue area in 2012 and the Brentwood area in 2015. It is considered established in St. Louis.
Symptoms of Spot Anthracnose: Spot anthracnose is caused by the fungus, Elsinoe corni. Symptoms include small, dark, pinprick lesions with purple borders on leaf surfaces. The lesions are numerous and usually occur on dry leaves. The disease is unsightly, but typically not very harmful.
Symptoms of Powdery Mildew: Powdery mildew is caused by the fungus, Microsphaera pulchra. Early symptoms include round, white or gray powder-like spots that appear on upper leaf surfaces. These spots form a dry white layer on leaves. As young leaves become infected, they appear twisted, dry, and leathery. Older leaves look bronzed. Moderate temperatures, low light, and high humidity accelerate this disease. High nitrogen levels cause the disease to flourish.
Integrated Pest Management Strategies
1. Choose disease resistant varieties. A soon-to-be released cultivar for dogwood anthracnose resistance is called ‘Appalachian Spring’. Cultivars less susceptible to spot anthracnose include ‘Cherokee Princess’, ‘Cherokee Sunset’, and ‘Springtime’. ‘Cherokee Brave’, C. kousa, and C. kousa x C. florida crosses are resistant to powdery mildew.
2. Water the roots of the tree. Avoid using overhead irrigation in order to reduce the incidence of leaf spot.
3. Practice good sanitation. Promptly remove and dispose of any dead or dying twigs or branches found in trees as well as leaves that show the symptoms of dogwood anthracnose. Leaves with spot anthrancnose and powdery mildew can remain but rake and remove them in the fall when they drop.
4. Remove plants confirmed with dogwood anthracnose. Removing an infected tree confirmed with dogwood anthracnose is strongly recommended. The infected trees should NOT be converted to mulch to avoid spreading the disease.
5. Apply fungicides. If you suspect dogwood anthracnose, get it diagnosed by a professional prior to a fungicide application. Powdery mildew should also be controlled, especially if the disease has occurred previously.
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文章
Dummer. ゛☀
2017年09月19日
Guignardia blotch is a foliage disease of many Aesculus species, including California, Ohio, red, and yellow buckeye and common, red, and Japanese horse chestnuts. Bottlebrush buckeye (A. parviflora) and some varieties of Ohio buckeye (A. glabra varieties arguta, monticola, and sargentii) may be resistant.
The leaves of affected plants develop large reddish brown blotches surrounded by yellow tissue, often causing the foliage to curl and brown. In severe cases, leaves may fall prematurely in late summer. Since the foliage is usually not badly damaged until after the tree has completed much of its annual growth, the disease is primarily aesthetic.
Wet weather promotes the growth of Guignardia blotch. In the United States, this fungal disease only occurs east of the Great Plains, perhaps because of the drier conditions of the West. This disease may become severe in nurseries or in plantings where tree crowns are close together.
Symptoms and Diagnosis
Guignardia blotch first appears as water-soaked irregular areas. These enlarge quickly and in a few days are reddish-brown to brown leaf spots with clear bright yellow margins. The blotches vary in size and may frequently grow together, covering large areas of leaf tissue. This causes the leaf to curl and brown, becoming dry and brittle, and may cause early leaf drop. Fruiting bodies of the fungus, seen as black pinhead-sized specks, may be visible in the lesions. Occasionally petioles and immature fruit may also have small reddish brown lesions. Symptoms of this disease are similar to those of environmental leaf scorch. Leaves affected by scorch will be on the sunny or windy side of the tree while Guignardia blotch may affect most leaves. Scorched leaves will not have the black fruiting bodies. See also “Scorch of Trees and Shrubs”.
Life Cycle
The Guignardia fungus overwinters on fallen Aesculus leaves. In early spring, its fruiting bodies mature and during wet weather, they release spores into the air. If the spores land on newly developing susceptible leaves that remain wet for several hours, the leaves become infected, resulting in blotches within 10–20 days. New fruiting bodies develop in early June and in wet weather, more infections may continue throughout the summer.
Integrated Pest Management Strategies
1. Sanitation. Rake and dispose of infected leaves.
2. Pruning. Thin the tree canopy to improve air circulation and to speed drying of leaves.
3. Fungicides. Chemical treatment is usually not necessary or recommended in the home landscape. Serious damage may be controlled by applying a fungicide containing chlorothalonil or mancozeb at bud break and then repeating the application at 10 to 14 day intervals as long as wet conditions continue.
The leaves of affected plants develop large reddish brown blotches surrounded by yellow tissue, often causing the foliage to curl and brown. In severe cases, leaves may fall prematurely in late summer. Since the foliage is usually not badly damaged until after the tree has completed much of its annual growth, the disease is primarily aesthetic.
Wet weather promotes the growth of Guignardia blotch. In the United States, this fungal disease only occurs east of the Great Plains, perhaps because of the drier conditions of the West. This disease may become severe in nurseries or in plantings where tree crowns are close together.
Symptoms and Diagnosis
Guignardia blotch first appears as water-soaked irregular areas. These enlarge quickly and in a few days are reddish-brown to brown leaf spots with clear bright yellow margins. The blotches vary in size and may frequently grow together, covering large areas of leaf tissue. This causes the leaf to curl and brown, becoming dry and brittle, and may cause early leaf drop. Fruiting bodies of the fungus, seen as black pinhead-sized specks, may be visible in the lesions. Occasionally petioles and immature fruit may also have small reddish brown lesions. Symptoms of this disease are similar to those of environmental leaf scorch. Leaves affected by scorch will be on the sunny or windy side of the tree while Guignardia blotch may affect most leaves. Scorched leaves will not have the black fruiting bodies. See also “Scorch of Trees and Shrubs”.
Life Cycle
The Guignardia fungus overwinters on fallen Aesculus leaves. In early spring, its fruiting bodies mature and during wet weather, they release spores into the air. If the spores land on newly developing susceptible leaves that remain wet for several hours, the leaves become infected, resulting in blotches within 10–20 days. New fruiting bodies develop in early June and in wet weather, more infections may continue throughout the summer.
Integrated Pest Management Strategies
1. Sanitation. Rake and dispose of infected leaves.
2. Pruning. Thin the tree canopy to improve air circulation and to speed drying of leaves.
3. Fungicides. Chemical treatment is usually not necessary or recommended in the home landscape. Serious damage may be controlled by applying a fungicide containing chlorothalonil or mancozeb at bud break and then repeating the application at 10 to 14 day intervals as long as wet conditions continue.
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文章
Dummer. ゛☀
2017年09月19日
Scale insects are common pests of many trees and shrubs. There are two general types of scale– armored scale and soft scales. A few of the species that fall into the armored scales are oystershell scale, San Jose scale, euonymus scale, and pine needle scale. Some soft scales are cottony maple scale, magnolia scale, and tuliptree scale. Scale coverings range in size, shape, and color depending on species.
Symptoms and Diagnosis
Trees heavily infested with armored scale often look water-stressed. Leaves turn yellow and drop, twigs and limbs may die, and the bark cracks and gums. Armored scales can kill trees and must be controlled when their population gets too high.
Soft scales also reduce plant vigor, but usually not enough to kill the plant. The main problem soft scales cause is the large amounts of honeydew they produce, which can cover leaves and fruit and act as a growth medium for black, sooty mold. Honeydew also attracts ants, flies, wasps, and bees that can become a nuisance.
Scale are identified by their body covering, which normally appears as a colored raised area on the leaf or stem of the plant that can be flicked off with the point of a knife or a fingernail. They vary in size but are generally only about 1/8 inch long.
Life Cycle
The life cycle of each species of scale can vary depending on the season and species. Armored scales usually have several generations a year, while soft scales have a single generation.
Scale overwinters on leaves, needles, stems, or twigs of the infested plant under the covering (shell) it creates. Under the scale shell, the female lays eggs. In the spring, the eggs hatch and the unprotected larvae (crawlers) emerge from under the protective shell and begin feeding on their own. The actual date of emergence varies with each type of scale insect and the weather. New plants can be infested when crawlers walk or are blown by the wind to a nearby plant. After a few days, the crawlers of armored scales settle down permanently, molt (and lose their legs), and begin to form their covering. Soon winged adult males crawl out from beneath their cover and mate with covered females. Adult male scales are tiny, winged, and seldom seen. Soft scale crawlers move about the plant a little longer after hatching before they settle down at a permanent feeding site. Some soft scale species move around during their immature stages and retain their legs for life. Their covers may be smooth or cottony, but they are firmly attached to their bodies. Soft scale tends to be larger than armored scale. Mature scales never move once they firmly attach themselves to the plant.
Integrated Pest Management Strategies
1. Maintain plant vigor. Maintaining a healthy plant is the best way to prevent infection by diseases or attack by insects. This can be accomplished by proper care including watering, fertilizing, providing a well-draining soil medium, adequate lighting, and air movement.
2. Pruning. Prune out heavily infested shoots or limbs. This will reduce the population and foster growth of new un-infested shoots.
3. Manual. Remove scale manually by rubbing them off the plant using your hand or a toothbrush. In the case of houseplants, use a cotton swab and rubbing alcohol.
4. Biological. Natural enemies, such as the ladybird beetle (ladybug) and small parasitic wasps, help control many scale species. Inspect the scale for round exit holes made by the emerging adult parasites. Before applying any insecticides, check the plant for the presence of the natural enemies and make sure that they are not already reducing scale numbers. If pesticide treatment is deemed necessary, confine the treatment to only those plants infested.
5. Chemical control. Many scale species on deciduous trees can be effectively controlled with either a dormant spray of refined horticultural, superior-type oil or summer oil spray or both. Oils and insecticidal soaps work by smothering the insect, both adults and crawlers. Other insecticides registered for use include malathion, bifenthrin, imidacloprid and pyrethrins.
6. Timing. Broad spectrum insecticidal treatments are most effective when applied in the crawler stage. Monitor by using double-sided sticky tape around some branches of the tree. Crawlers appear as tiny, pale yellow specks ("fried eggs") on the tape.
7.Repeat. In the case of overlapping generations, where every stage of development occurs, two to four applications at ten-day intervals will be needed.
8. Directions. Read and follow label directions. Check to insure the type scale and the host plant are listed on the label before using any insecticide.
Symptoms and Diagnosis
Trees heavily infested with armored scale often look water-stressed. Leaves turn yellow and drop, twigs and limbs may die, and the bark cracks and gums. Armored scales can kill trees and must be controlled when their population gets too high.
Soft scales also reduce plant vigor, but usually not enough to kill the plant. The main problem soft scales cause is the large amounts of honeydew they produce, which can cover leaves and fruit and act as a growth medium for black, sooty mold. Honeydew also attracts ants, flies, wasps, and bees that can become a nuisance.
Scale are identified by their body covering, which normally appears as a colored raised area on the leaf or stem of the plant that can be flicked off with the point of a knife or a fingernail. They vary in size but are generally only about 1/8 inch long.
Life Cycle
The life cycle of each species of scale can vary depending on the season and species. Armored scales usually have several generations a year, while soft scales have a single generation.
Scale overwinters on leaves, needles, stems, or twigs of the infested plant under the covering (shell) it creates. Under the scale shell, the female lays eggs. In the spring, the eggs hatch and the unprotected larvae (crawlers) emerge from under the protective shell and begin feeding on their own. The actual date of emergence varies with each type of scale insect and the weather. New plants can be infested when crawlers walk or are blown by the wind to a nearby plant. After a few days, the crawlers of armored scales settle down permanently, molt (and lose their legs), and begin to form their covering. Soon winged adult males crawl out from beneath their cover and mate with covered females. Adult male scales are tiny, winged, and seldom seen. Soft scale crawlers move about the plant a little longer after hatching before they settle down at a permanent feeding site. Some soft scale species move around during their immature stages and retain their legs for life. Their covers may be smooth or cottony, but they are firmly attached to their bodies. Soft scale tends to be larger than armored scale. Mature scales never move once they firmly attach themselves to the plant.
Integrated Pest Management Strategies
1. Maintain plant vigor. Maintaining a healthy plant is the best way to prevent infection by diseases or attack by insects. This can be accomplished by proper care including watering, fertilizing, providing a well-draining soil medium, adequate lighting, and air movement.
2. Pruning. Prune out heavily infested shoots or limbs. This will reduce the population and foster growth of new un-infested shoots.
3. Manual. Remove scale manually by rubbing them off the plant using your hand or a toothbrush. In the case of houseplants, use a cotton swab and rubbing alcohol.
4. Biological. Natural enemies, such as the ladybird beetle (ladybug) and small parasitic wasps, help control many scale species. Inspect the scale for round exit holes made by the emerging adult parasites. Before applying any insecticides, check the plant for the presence of the natural enemies and make sure that they are not already reducing scale numbers. If pesticide treatment is deemed necessary, confine the treatment to only those plants infested.
5. Chemical control. Many scale species on deciduous trees can be effectively controlled with either a dormant spray of refined horticultural, superior-type oil or summer oil spray or both. Oils and insecticidal soaps work by smothering the insect, both adults and crawlers. Other insecticides registered for use include malathion, bifenthrin, imidacloprid and pyrethrins.
6. Timing. Broad spectrum insecticidal treatments are most effective when applied in the crawler stage. Monitor by using double-sided sticky tape around some branches of the tree. Crawlers appear as tiny, pale yellow specks ("fried eggs") on the tape.
7.Repeat. In the case of overlapping generations, where every stage of development occurs, two to four applications at ten-day intervals will be needed.
8. Directions. Read and follow label directions. Check to insure the type scale and the host plant are listed on the label before using any insecticide.
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文章
Dummer. ゛☀
2017年09月18日
Jungle Cacti are a group of cacti that grow in rain forests. Unlike their desert relatives, these plants do not resemble one another and many do not have spines. Jungle Cacti include those species in genera such as Acanthocereus, Disocactus, Epiphyllum, Hatiora, Hylocereus, Lepismium, Rhipsalis, Schlumbergera, Selenicereus, and perhaps a few others. Almost everyone has seen at least one representative from this group even if they were unaware that the plant was actually a cactus. The most common of these are the Holiday Cacti: Easter Cactus (Hatiora gaertneri), Thanksgiving Cactus (Schlumbergera truncata) and Christmas Cactus (Schlumbergera x buckleyi). These plants are all true cacti despite their lack of big spines and inability to withstand the harsh conditions of the desert. Now when we associate “cactus” with one of these, it does not seem unusual that they would require different care when growing than the stereotypical image that comes to mind when we think about the family Cactaceae.
Soil
Most Jungle Cacti are either epiphytic or lithophytic meaning they grow in trees or grow on rocks respectively. This type of plant gets its nutrients from the air or from dead leaves and other debris that may have collected in crotches, cracks, or crevasses. It is important to note that there are no parasitic cacti. Those that grow in trees do so for support, but do not sap nutrients from their host. For best results we’ll want our soil to mimic these natural conditions.
Some good ingredients for creating a suitable potting mixture for Jungle Cacti include: orchid bark, pearlite, potting soil, peat, coir, pumice, and oak leaf mold. The most important aspect of the mixture is good drainage. The pearlite helps create this by keeping the soil loose and “airy” and so does the orchid bark. Additionally the orchid bark tends to hold more moisture than pearlite or gravel. Pumice can be substituted for the pearlite. Keep in mind that the orchid bark will eventually break down into soil. This will create a very rich soil that may not be as effective in keeping the roots healthy. Repot your Jungle Cacti every 2 or three years with a fresh mix. The best time to do this is shortly after your plant has finished blooming. This is when it will be ready to start growing again. You might also add some fertilizer to the new mix.
Water
Well drained soil is critical for keeping the water from rotting the roots off the plant. With the proper soil, however, watering is really quite simple. The easiest way to gauge whether or not it’s time to water is to stick your finger in the top 0.5 inch (1.2 cm) of soil. If the soil is dry, go ahead and water. If it’s not, wait! Don’t let your Jungle Cactus go too long without water. If the stem segments are shriveled and the soil is dry, it is probably in need of water. Be careful! If the plant is over watered, the stems will also look shriveled, but the soil will be damp. If this is the case, do not give it more water. An over-watered plant will start to turn yellowish, then get more and more mushy and dark reddish-brown like a rotten apple. This is because the cells took in so much water they broke and are now dead and rotting. This usually happens from the ends first. This will continue even after you stop watering too much, but often you will have enough plant left to start over.
Light
Jungle Cacti can survive in a wide range of light conditions. However, we’ll assume the goal is not to have plants simply surviving, but thriving. For the plants to thrive the amount and intensity of light are key ingredients.
There are three lighting situations that are not as ideal, but often times necessary due to space constraints. These are morning shade/full afternoon sun, full shade, and full sun. Let’s explore these conditions further. It may seem that shade in the morning and full-sun in the afternoon should produce the same results as full morning sun/afternoon shade, but it doesn’t. This is because the temperature is cooler in the morning than the afternoon and for many plants the afternoon sun is a little too intense and plants will often take on a sickly-yellow appearance and may develop spots. In full-sun these symptoms will be even more apparent. As with most things in nature there are exceptions and some plants actually prefer full-sun and thrive in it. In full shade the plants will don a dark-green healthy appearance, but the stems will be stretched out long and thin in an attempt to reach more light.
Not only is light essential for healthy stems, it also triggers blooming in many species. In ideal conditions a particular plant may exhibit fantastic growth with many show-quality stems, but they won’t bloom. In this situation exposing the plant to longer and more intense sunlight will trigger it to bloom. Don’t forget that plants can get sunburn just like people do. If you have a plant that has been mostly shaded, don’t just stick it out in direct sunlight or you will certainly end up with a badly scared cactus. This is even true for desert cacti that occur naturally in extremely hot, intense sunlight.
Soil
Most Jungle Cacti are either epiphytic or lithophytic meaning they grow in trees or grow on rocks respectively. This type of plant gets its nutrients from the air or from dead leaves and other debris that may have collected in crotches, cracks, or crevasses. It is important to note that there are no parasitic cacti. Those that grow in trees do so for support, but do not sap nutrients from their host. For best results we’ll want our soil to mimic these natural conditions.
Some good ingredients for creating a suitable potting mixture for Jungle Cacti include: orchid bark, pearlite, potting soil, peat, coir, pumice, and oak leaf mold. The most important aspect of the mixture is good drainage. The pearlite helps create this by keeping the soil loose and “airy” and so does the orchid bark. Additionally the orchid bark tends to hold more moisture than pearlite or gravel. Pumice can be substituted for the pearlite. Keep in mind that the orchid bark will eventually break down into soil. This will create a very rich soil that may not be as effective in keeping the roots healthy. Repot your Jungle Cacti every 2 or three years with a fresh mix. The best time to do this is shortly after your plant has finished blooming. This is when it will be ready to start growing again. You might also add some fertilizer to the new mix.
Water
Well drained soil is critical for keeping the water from rotting the roots off the plant. With the proper soil, however, watering is really quite simple. The easiest way to gauge whether or not it’s time to water is to stick your finger in the top 0.5 inch (1.2 cm) of soil. If the soil is dry, go ahead and water. If it’s not, wait! Don’t let your Jungle Cactus go too long without water. If the stem segments are shriveled and the soil is dry, it is probably in need of water. Be careful! If the plant is over watered, the stems will also look shriveled, but the soil will be damp. If this is the case, do not give it more water. An over-watered plant will start to turn yellowish, then get more and more mushy and dark reddish-brown like a rotten apple. This is because the cells took in so much water they broke and are now dead and rotting. This usually happens from the ends first. This will continue even after you stop watering too much, but often you will have enough plant left to start over.
Light
Jungle Cacti can survive in a wide range of light conditions. However, we’ll assume the goal is not to have plants simply surviving, but thriving. For the plants to thrive the amount and intensity of light are key ingredients.
There are three lighting situations that are not as ideal, but often times necessary due to space constraints. These are morning shade/full afternoon sun, full shade, and full sun. Let’s explore these conditions further. It may seem that shade in the morning and full-sun in the afternoon should produce the same results as full morning sun/afternoon shade, but it doesn’t. This is because the temperature is cooler in the morning than the afternoon and for many plants the afternoon sun is a little too intense and plants will often take on a sickly-yellow appearance and may develop spots. In full-sun these symptoms will be even more apparent. As with most things in nature there are exceptions and some plants actually prefer full-sun and thrive in it. In full shade the plants will don a dark-green healthy appearance, but the stems will be stretched out long and thin in an attempt to reach more light.
Not only is light essential for healthy stems, it also triggers blooming in many species. In ideal conditions a particular plant may exhibit fantastic growth with many show-quality stems, but they won’t bloom. In this situation exposing the plant to longer and more intense sunlight will trigger it to bloom. Don’t forget that plants can get sunburn just like people do. If you have a plant that has been mostly shaded, don’t just stick it out in direct sunlight or you will certainly end up with a badly scared cactus. This is even true for desert cacti that occur naturally in extremely hot, intense sunlight.
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0
文章
Dummer. ゛☀
2017年09月18日
Dyckia is a genus of bromeliad found within the Pitcairnioideae subfamily of Bromeliads. There are 120 different species with many more cultivars. Most species are native to Brazil, but a few originate from other South American countries such as Uruguay, Paraguay and Bolivia.
The genus was introduced into Europe during the nineteenth century, and was named for Prince von Salm-Dyck, an early expert on succulents. Dyckias are not technically succulents, as they do not store water in their leaves like true succulents. They are xerographic and survive long periods without water by going dormant. Their rosette of thick succulent leaves will eventually wilt, but recovery is rapid when watering is resumed.
The leaves vary from long and strappy to short and scalloped. All foliage is fairly rigid and may be smooth or serrated, a solid color or variegated or spotted. Long stalks with multiple red, yellow, or orange flowers appear in spring. The wide range of varieties ensures that there is a specimen for every taste.
Growing Conditions
Most of the plants survive in warm regions with heavy rainfall for half the year and very dry conditions the rest of the time. This makes Dyckia care slightly challenging, as getting the right balance of moisture to keep the plant happy may be difficult. Dyckia growing conditions in their natural setting should be mimicked as much as possible.
In their native region, it is not uncommon to find some forms growing on top of rocks near water. Water and the cycle of the monsoon season are important features to Dyckia health. They are used to rather poor soil when they do grow in ground and should be planted in a good succulent mixture.
Dyckia need full sun and temperatures of up to 90°F (32°C) to thrive. Beware of exposing the plants to freezing temperatures for more than a brief time as they are not cold hardy. Temperatures below 40°F (4°C) seem to be the limit of Dyckia growing conditions.
Dyckia are exposed to harsh sun and very dry conditions for most of the year. Then the rainy season appears and the plants are half drowned. Contrary to common sense, they seem to love this treatment and plants are healthiest when the monsoon season is harsh and long.
General Care
While actively growing, the plants need regular water to produce happy plants. The soil should not be soggy but evenly moist at all times. Use a saucer under potted plants to keep the roots from sitting in water but allow for evaporation and consistent humidity. In winter, when growth is dormant, you may reduce the amount of water by half.
Fertilize from spring to fall with a half strength liquid plant food. In the wild, the plants form pups or offsets, which result in new plants. The same is true in container grown plants and these can be divided away from the parent with ease.
The plants set seed readily when flowers are present and these germinate quickly. However, they also freely hybridize and the species resulting from the seed may not represent the parent.
The genus was introduced into Europe during the nineteenth century, and was named for Prince von Salm-Dyck, an early expert on succulents. Dyckias are not technically succulents, as they do not store water in their leaves like true succulents. They are xerographic and survive long periods without water by going dormant. Their rosette of thick succulent leaves will eventually wilt, but recovery is rapid when watering is resumed.
The leaves vary from long and strappy to short and scalloped. All foliage is fairly rigid and may be smooth or serrated, a solid color or variegated or spotted. Long stalks with multiple red, yellow, or orange flowers appear in spring. The wide range of varieties ensures that there is a specimen for every taste.
Growing Conditions
Most of the plants survive in warm regions with heavy rainfall for half the year and very dry conditions the rest of the time. This makes Dyckia care slightly challenging, as getting the right balance of moisture to keep the plant happy may be difficult. Dyckia growing conditions in their natural setting should be mimicked as much as possible.
In their native region, it is not uncommon to find some forms growing on top of rocks near water. Water and the cycle of the monsoon season are important features to Dyckia health. They are used to rather poor soil when they do grow in ground and should be planted in a good succulent mixture.
Dyckia need full sun and temperatures of up to 90°F (32°C) to thrive. Beware of exposing the plants to freezing temperatures for more than a brief time as they are not cold hardy. Temperatures below 40°F (4°C) seem to be the limit of Dyckia growing conditions.
Dyckia are exposed to harsh sun and very dry conditions for most of the year. Then the rainy season appears and the plants are half drowned. Contrary to common sense, they seem to love this treatment and plants are healthiest when the monsoon season is harsh and long.
General Care
While actively growing, the plants need regular water to produce happy plants. The soil should not be soggy but evenly moist at all times. Use a saucer under potted plants to keep the roots from sitting in water but allow for evaporation and consistent humidity. In winter, when growth is dormant, you may reduce the amount of water by half.
Fertilize from spring to fall with a half strength liquid plant food. In the wild, the plants form pups or offsets, which result in new plants. The same is true in container grown plants and these can be divided away from the parent with ease.
The plants set seed readily when flowers are present and these germinate quickly. However, they also freely hybridize and the species resulting from the seed may not represent the parent.
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文章
Dummer. ゛☀
2017年09月18日
Lampranthus is a fairly large genus with 100-150 species coming from South Africa. It provides some of the most spectacular displays of bright flowers from the succulent world, and is widely used as ground cover, either annual or perennial as the climate allows. Several species are used for landscaping and vary from shrubby to trailing, and they also for the flowering period. All the species tend to become woody as they age.
The genus name “Lampranthus” means “shining-flowers” in Latin, and the species of this genus have large, extremely bright flowers, of a range of colors (sometimes even bi-colored), that usually appear in summer, and frequently cover the plants entirely. The species of this genus typically have long, smooth, elongated, succulent leaves. These can be triangular or cylindrical, and appear in opposite pairs on the shrubs’ branches.
The spectacular flowers need full sun to open. As most mesemb, they are followed by woody capsules that open when wet, to insure propagation of the seeds at the best possible time.
Growing Conditions and General Care
Lampranthus are generally hardy in U.S. Department of Agriculture plant hardiness zones 8 through 11, but this varies depending on the species.
Lampranthus thrive in well-drained, poor soils and are suitable for soils with a sandy or rocky texture, although they’ll grow in almost any soil type. They tolerate exposure to salt and grow in coastal conditions. Plant rooted cuttings in spring after the possibility of frost has passed. Space the cuttings 6 to 24 inches (15 to 60 cm) apart for trailing species, using closer spacings for quicker coverage. Dig a hole just a little larger than the roots at the cutting’s base. Put the roots in the hole, cover them with soil and tamp the soil firmly in place. For erect or mounding species, space them according to the mature dimensions for the particular species.
Water the plants immediately after planting, but then let the top inch of soil dry before watering again. Water the plants in this manner through the first spring and summer they are in place. They are drought-tolerant once established, when they will need watering only during extended dry periods.
Lampranthus need full sun to keep the growth from becoming leggy and for best flowering. They don’t need fertilizing, as that causes overgrowth of softer, weaker branches. After plants flower, prune off the old flowers and any developing fruits. Lampranthus are short-lived perennials and may need replacement after several years.
For container Lampranthus, use a cactus and succulent potting mix. Containers need watering throughout the year whenever the top layer of soil dries out. Plants can grow almost year-round in mild climates. Prune as needed any time of year to keep the plant to size. Bring containers indoors before the first frost is predicted.
Propagation
The propagation is by seed or cuttings. Seeds need warmth to germinate, 60°F (16°C) or more is suggested. Cuttings should be taken in summer. Six inch (15 cm) shoot stripped of their bottom leaves and planted in moist sand should rapidly root.
The genus name “Lampranthus” means “shining-flowers” in Latin, and the species of this genus have large, extremely bright flowers, of a range of colors (sometimes even bi-colored), that usually appear in summer, and frequently cover the plants entirely. The species of this genus typically have long, smooth, elongated, succulent leaves. These can be triangular or cylindrical, and appear in opposite pairs on the shrubs’ branches.
The spectacular flowers need full sun to open. As most mesemb, they are followed by woody capsules that open when wet, to insure propagation of the seeds at the best possible time.
Growing Conditions and General Care
Lampranthus are generally hardy in U.S. Department of Agriculture plant hardiness zones 8 through 11, but this varies depending on the species.
Lampranthus thrive in well-drained, poor soils and are suitable for soils with a sandy or rocky texture, although they’ll grow in almost any soil type. They tolerate exposure to salt and grow in coastal conditions. Plant rooted cuttings in spring after the possibility of frost has passed. Space the cuttings 6 to 24 inches (15 to 60 cm) apart for trailing species, using closer spacings for quicker coverage. Dig a hole just a little larger than the roots at the cutting’s base. Put the roots in the hole, cover them with soil and tamp the soil firmly in place. For erect or mounding species, space them according to the mature dimensions for the particular species.
Water the plants immediately after planting, but then let the top inch of soil dry before watering again. Water the plants in this manner through the first spring and summer they are in place. They are drought-tolerant once established, when they will need watering only during extended dry periods.
Lampranthus need full sun to keep the growth from becoming leggy and for best flowering. They don’t need fertilizing, as that causes overgrowth of softer, weaker branches. After plants flower, prune off the old flowers and any developing fruits. Lampranthus are short-lived perennials and may need replacement after several years.
For container Lampranthus, use a cactus and succulent potting mix. Containers need watering throughout the year whenever the top layer of soil dries out. Plants can grow almost year-round in mild climates. Prune as needed any time of year to keep the plant to size. Bring containers indoors before the first frost is predicted.
Propagation
The propagation is by seed or cuttings. Seeds need warmth to germinate, 60°F (16°C) or more is suggested. Cuttings should be taken in summer. Six inch (15 cm) shoot stripped of their bottom leaves and planted in moist sand should rapidly root.
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文章
Dummer. ゛☀
2017年09月18日
Echeveria elegans, also known as Mexican Snowball is a dense, blue-gray succulent species from Mexico that mounds or spreads slowly in tight colonies. Edges of leaves are slightly pink, producing equally pretty small pink flowers with a yellow tinge. Very handsome and uniform in the garden.
Mexican Snowball is aptly named for two reasons: the succulent rosettes are an icy blue color and this species is the hardiest of the Echeveria, a genus of succulents with their center of diversity in Mexico.
The low-growing clusters are very suitable to fill rock crevices and are occasionally used to cover the roof tiles of a house‐top. A layer of rosettes stapled to the roof overhang is used to hold an inch of peaty soil to the roof. It is also used to form silvery blue small borders and are believed to keep away evil spirits.
Growing Conditions
Light: Grow Echeveria elegans in full sun to light shade.
Water: Water moderately when in growth; not at all when dormant.
Temperature: More cold hardy than many other Echeverias, this one makes an excellent rock garden or container plant that needs occasional winter protection below 25°F (-4°C).
Soil: Grow in well-drained soil.
Fertilizer: Apply a balanced liquid fertilizer 2 or 3 times in the growing season.
Grower’s Tips
Mexican Snowball is certainly one of the most versatile neat, low-growing ground cover succulents. It is easy to care for and is a good starting point for beginning gardeners. It is considered to be drought tolerant but it does best with occasional watering in a well drained soil. This is typical of many Echeveria. They can be planted in full sun in coastal areas and they like some light shade when planted inland. Elsewhere grow as a houseplant in winter in a cool, bright window and keep dry until spring.
Propagation
Propagate by seed sown as soon as ripe or by root, stem or leaf cuttings in spring.
Mexican Snowball is aptly named for two reasons: the succulent rosettes are an icy blue color and this species is the hardiest of the Echeveria, a genus of succulents with their center of diversity in Mexico.
The low-growing clusters are very suitable to fill rock crevices and are occasionally used to cover the roof tiles of a house‐top. A layer of rosettes stapled to the roof overhang is used to hold an inch of peaty soil to the roof. It is also used to form silvery blue small borders and are believed to keep away evil spirits.
Growing Conditions
Light: Grow Echeveria elegans in full sun to light shade.
Water: Water moderately when in growth; not at all when dormant.
Temperature: More cold hardy than many other Echeverias, this one makes an excellent rock garden or container plant that needs occasional winter protection below 25°F (-4°C).
Soil: Grow in well-drained soil.
Fertilizer: Apply a balanced liquid fertilizer 2 or 3 times in the growing season.
Grower’s Tips
Mexican Snowball is certainly one of the most versatile neat, low-growing ground cover succulents. It is easy to care for and is a good starting point for beginning gardeners. It is considered to be drought tolerant but it does best with occasional watering in a well drained soil. This is typical of many Echeveria. They can be planted in full sun in coastal areas and they like some light shade when planted inland. Elsewhere grow as a houseplant in winter in a cool, bright window and keep dry until spring.
Propagation
Propagate by seed sown as soon as ripe or by root, stem or leaf cuttings in spring.
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文章
Dummer. ゛☀
2017年09月18日
Calandrinia is a plant genus that contains many species of purslane, including the redmaids. The genus was named for Jean Louis Calandrini, an 18th-century Swiss botanist. It includes around 150 species of annual herbs which bear colorful flowers in shades of red to purple and white. Plants of this genus are native to Australia, Chile, and western North America.
Calandrinia are half hardy perennials and annuals. As the perennials have a short life span they are usually grown as half hardy annuals in the garden. They are low growing, reaching heights of about 6 to 18 inches (15 to 45 cm) and bloom with hundreds of bright pink and purple flowers from middle to late summer. Names for Calandrinia include Rock Purslane, Parakeelya and Redmaids. They are ideal, ground cover and edging plants, they can also be used in rockeries. Plants are able to grow in very hot conditions.
Growing Conditions and General Care
Calandrinia plants are very easy to care for as they can tolerate prolonged dry periods. They do not like to much water, especially in the winter. Plants are able to grow as a short lived perennial in warm regions but should be grown as annuals elsewhere. Propagate by taking cuttings or allow plants to self seed in situ.
If you plan to grow outdoors from seed then Calandrinia species should be sown at a depth of 0.1 inch (3 mm) after the last frost of spring. If you prefer to start off Calandrinia as seeds indoors then they should be started off about eight weeks before they are due to be put out.
They should be grown at a temperature of 55 to 59°F (13 to 15°C), and take from one to two weeks to germinate. The seedlings of Calandrinia should be planted out with a spacing of about 8 inches (20 cm) following the last possible frost of spring into an area that receives plenty of sun, and into a gritty or sandy soil.
Calandrinia are half hardy perennials and annuals. As the perennials have a short life span they are usually grown as half hardy annuals in the garden. They are low growing, reaching heights of about 6 to 18 inches (15 to 45 cm) and bloom with hundreds of bright pink and purple flowers from middle to late summer. Names for Calandrinia include Rock Purslane, Parakeelya and Redmaids. They are ideal, ground cover and edging plants, they can also be used in rockeries. Plants are able to grow in very hot conditions.
Growing Conditions and General Care
Calandrinia plants are very easy to care for as they can tolerate prolonged dry periods. They do not like to much water, especially in the winter. Plants are able to grow as a short lived perennial in warm regions but should be grown as annuals elsewhere. Propagate by taking cuttings or allow plants to self seed in situ.
If you plan to grow outdoors from seed then Calandrinia species should be sown at a depth of 0.1 inch (3 mm) after the last frost of spring. If you prefer to start off Calandrinia as seeds indoors then they should be started off about eight weeks before they are due to be put out.
They should be grown at a temperature of 55 to 59°F (13 to 15°C), and take from one to two weeks to germinate. The seedlings of Calandrinia should be planted out with a spacing of about 8 inches (20 cm) following the last possible frost of spring into an area that receives plenty of sun, and into a gritty or sandy soil.
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文章
Dummer. ゛☀
2017年09月18日
The genus Matucana belongs to the family of Cactaceae and is a native of Peru, particularly of the Andean city of Matucana, from which it takes its name. The genus includes about 20 species currently spread throughout South America. The plants grow in the highlands of the Andes at above 2500 m of altitude. Sturdy, robust, the Matucana are quite popular among collectors for its ease of cultivation.
Matucana is characterized by bright green plants, sized small and medium, both globular and cylindrical, with numerous ribs segmented into dense spines and tubercles. The bloom is apical and flowers, usually appearing in late spring or summer, are elongated and tubular. They hatch at night and lasts from 2 to 4 days, offering a wide variety of colors, from white to red, yellow and bright orange.
Growing Conditions and General Care
All species are sensitive to moisture. Watering should therefore be limited to the growing season and should be made only when the substrate is completely dry. It must be suspended during the winter. Since they tend to lose their roots in cold and wet, these plants must be kept warm even in winter. A temperature not under 50°F (10°C) is suitable. Some species, for natural adaptation, can resist at temperatures below 32°F (0°C).
If the plants are in the vegetative stage and optimal environmental conditions (a low moisture content with substantial temperature swing between day and night is appreciated), the growth is quite fast and you can get blooms already after 2-3 years after birth.
Matucana must be grown in a very porous and draining soil. It can be composed largely by sand, lapilli and gravel. To encourage the development of a dense network of spine, the quality of the nutrients in the substrate is very important. The soil must be rich in potassium, poor in nitrogen. Since the roots are very delicate and subject to rot, the soil should be kept as dry as possible: do not forget that in their natural environment these plants grow in steep and inaccessible places.
Matucana like dry, fresh and light air. A direct exposure to sunlight is appropriated, but too high temperatures (above 90°F/32°C), very different from those of their original environment, may damage them. In these cases it is best to filter the sun’s rays or prefer a bright area anyway, but at least partially shaded.
Propagation
Propagation is easy by seed, sowing should preferably be done in the spring.
Matucana is characterized by bright green plants, sized small and medium, both globular and cylindrical, with numerous ribs segmented into dense spines and tubercles. The bloom is apical and flowers, usually appearing in late spring or summer, are elongated and tubular. They hatch at night and lasts from 2 to 4 days, offering a wide variety of colors, from white to red, yellow and bright orange.
Growing Conditions and General Care
All species are sensitive to moisture. Watering should therefore be limited to the growing season and should be made only when the substrate is completely dry. It must be suspended during the winter. Since they tend to lose their roots in cold and wet, these plants must be kept warm even in winter. A temperature not under 50°F (10°C) is suitable. Some species, for natural adaptation, can resist at temperatures below 32°F (0°C).
If the plants are in the vegetative stage and optimal environmental conditions (a low moisture content with substantial temperature swing between day and night is appreciated), the growth is quite fast and you can get blooms already after 2-3 years after birth.
Matucana must be grown in a very porous and draining soil. It can be composed largely by sand, lapilli and gravel. To encourage the development of a dense network of spine, the quality of the nutrients in the substrate is very important. The soil must be rich in potassium, poor in nitrogen. Since the roots are very delicate and subject to rot, the soil should be kept as dry as possible: do not forget that in their natural environment these plants grow in steep and inaccessible places.
Matucana like dry, fresh and light air. A direct exposure to sunlight is appropriated, but too high temperatures (above 90°F/32°C), very different from those of their original environment, may damage them. In these cases it is best to filter the sun’s rays or prefer a bright area anyway, but at least partially shaded.
Propagation
Propagation is easy by seed, sowing should preferably be done in the spring.
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