#菊瘿蚊 分布与危害 分布区域：北京 河北 河南 安徽 重庆等地 为害作物：菊花 早菊各品种 悬崖菊 九月菊 万寿菊及菊科其他植物 为害症状：幼虫在菊株叶腋、顶端生长点及嫩叶上为害，形成绿色或紫绿色、上尖下圆的桃形虫瘿，为害重的菊株上虫瘿累累，植株生长缓慢，矮化畸形，影响座蕾和开花。 形态特征 成虫 雌成虫体长3-3．5mm，初羽化时桔红色，渐变为黑褐色，腹部暗桔红色，背部各节有黑色横斑。触角念珠状，17-19节，节间有毛，并有较短的轮生毛。足长，黄色。胸发达，胸背黑色。尾部较尖，有明显的管状能伸缩的产卵器。翅淡灰色，半透明，具微毛，端圆，有 3条明显的纵脉，无横脉。雄成虫体稍瘦小，长3mm左右。腹部灰至灰褐色。触角念珠状，17- 19节，节间毛及轮生毛均较长。前翅圆阔，具微毛，纵脉3条；后翅退化为平衡棍。腹背板黑色，腹部前6节较粗，后3、4节细长。卵 长0．5mm，长卵圆形，初桔红色，后呈紫红色。末龄幼虫体长3．5-4mm，橙黄色，纺锤形。头退化不显著。口针可收缩，端部具一弯曲钩，胸部有时发现有不大显著的剑骨片。裸蛹 长3-4mm，橙黄色，其外侧各具短毛1根。 发生规律 河北、河南年生5代，以老熟幼虫越冬。翌年3月化蛹，4月初成虫羽化，在菊花幼苗上产卵，第一代幼虫于4月上、中旬出现，田间不久出现虫瘿，5月上旬虫瘿随幼苗进入田间，5月中、下旬一代成虫羽化。卵散产或聚产在菊株的叶腋处和生长点。幼虫孵化后经1天即可蛀入菊株组织中，经5天左右形成虫瘿。随幼虫生长发育，虫瘿逐渐膨大。每个虫瘿中有幼虫 1.13头。幼虫老熟后，在瘿内化蛹。成虫多从虫瘿顶部羽化，羽化孔圆形，蛹壳露出孔口一半。以后各代都在菊花田内繁殖为害。第2代5月中下旬-6月中下旬发生；第3代6月下旬-8月上旬；第4代8月上旬-9月下旬；第5代9月下旬-10月下旬。10月下旬后幼虫老熟，从虫瘿里脱出，入土下1-2cm处作茧越冬。天敌有5种寄生蜂。 防治方法 (1)清除田间菊科植物杂草，减少虫源。 (2)避免从菊花瘿蚊发生严重地区引种菊苗，因菊花瘿蚊发生较早，苗期即可带卵和初孵幼虫。 (3)药剂防治成虫发生期可喷国光依它（45%丙溴辛硫磷）乳油1500倍液，国光必治1500倍液，50％辛硫磷乳油1000-1500倍液，杀死产卵成虫。 (4)保护天敌。该虫发生后期，当天敌数量大时，不要盲目使用化学药剂，以保护天敌充分发挥天敌的自然控制力，这样既可以控制后期为害，又可以压低明年春季的发生量。

You can find succulents in just about every garden center, big box store and even the grocery store now. While these plants are relatively easy to care for, there are times when your plants may not look very healthy. Even if you have the greenest of “green thumbs” (or not) here are a few tips to help keep your succulents healthy. [图片]1. You are Giving Them Too Much Water Succulents don’t need to be watered like your common or typical houseplant. Well drained soil is a must…water when the soil is dry. Give your plant a thorough soaking and let the excess water drain out. 2. The Planting Container is Too Small Did you find a cute tea cup or flower pot for your succulent? Sure it looks cute, but does it give the roots the room it needs to grow? Probably not. The depth of the container should be twice as deep as the roots of the plant, while the width should be at least three times as wide. This gives the plant plenty of room to spread out! [图片]3. The Planting Container Doesn’t Provide Drainage People love panting succulents in cute containers, but the truth is if they don’t have proper drainage they will never work. Your container should have several drainage holes where water can escape. A piece of net over the holes can help dirt from escaping in the process. 4. They aren’t Getting Enough Light Succulents love warm weather and plenty of light. Not every succulent needs to be in direct sunlight all day long, be sure to know the exact light requirements of your plants. Shade is NOT good for succulents, they will loose their color and will get “leggy” stretching for the light. 5. Your Soil Isn’t Nutrient Rich Succulents love nutrient rich soil. During the growing season, a balanced fertilizer, which has been diluted to 1/4 strength, can be added to the water for each watering. [图片]6. You Need to Transplant Them If your succulent has been in a container for several months and seems to be thriving, you need to repot it into a larger container. By doing so you will give it more room to grow and it won’t get cramped and smothered by its own roots. Are you ready to enjoy more healthy, vibrant, and ALIVE succulents? Give these 6 reasons your succulents are dying your consideration, make the changes needed, and enjoy the succulents you have always dreamed of.

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The principal perennial grassy weeds in lawns include Bermudagrass (Cynodon dactylon), nimblewill (Muhlenbergia schreberi), quackgrass (Elymus repens), wild fescue (Festuca pratensis), and in certain cases, zoysiagrass (Zoysia spp.). Each of these grasses, except wild fescue, is characterized by a vigorous, invasive growth habit under usual horticultural practices. They are especially troublesome in turf, because, unlike their common broadleaf counterparts, selective herbicides for their control are unknown. [图片]Integrated Pest Management Strategies 1. Dig or pull plants. This method can be effective for controlling invading, perennial grassy weeds in beds and other non-lawn spaces. Constant vigilance is required because remaining root fragments and other plant parts will usually sprout, leading to renewed infestation. This technique cannot be recommended for use in turf except on a very limited basis. The usual practices of maintaining healthy, vigorous lawns comprised of cool-season grasses will not exclude invasion by nimblewill, Bermudagrass, or zoysiagrass from infested adjoining plots. [图片]2. Use herbicides. Perennial grassy weeds can usually be controlled only by the application of non-selective, general purpose herbicides, e.g., glyphosate (Roundup, Kleenup) or glyfosinate. Small patches of these weeds in turf may be controlled by spot spraying. Of course, all vegetation will be killed, so the spotted turf must be repaired by proper soil preparation and overseeding with desirable species. Heavily infested, larger areas will probably require broadcast spraying of entire areas as a first step in lawn renovation. Whenever possible, this exercise should be carried out in late summer or early fall. Carefully directed sprays of non-selective herbicides have proven useful for controlling heavy infestation of perennial, grassy weeds in beds or other relatively open spaces. Desirable plants must be protected by adequate shielding to prevent contact with the herbicides during application. Although somewhat tedious, these materials may also be applied by carefully painting them on the weedy plants' surfaces. [图片]3. Use all herbicides according to label instructions. Equipment must be cleaned and should not be used for applications other than herbicides.

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Some of the most common perennial broadleaf weeds in Missouri lawns include bindweed, chicory, creeping bellflower, dandelion, ground ivy, mouseear chickweed, plantain, thistle, violets, and white clover. They differ from annual weeds in that they continue to grow year after year and once established, they are not affected by preemergent herbicides. [图片]Integrated Pest Management Strategies 1. Hand dig or spot treat. If only a few weeds are present, hand dig the weeds with a forked tool to cut the root off well below ground level. You can also spot treat using glyphosate (Roundup, Kleenup) or the chemicals listed below. Since glyphosate (Roundup, Kleenup) is NOT selective, it will also kill any grass you get it on so apply very carefully. This method works best with weeds such as thistle or large plantain plants. The herbicide can also be brushed on individual weeds, avoiding the grass. NOTE: 2,4-D products listed below used according to label directions will not damage grass caught in the overspray. 2. Use chemical herbicides. When problem areas are too large for spot treating, hose-end products are the easiest for homeowners to use. Garden centers and hardware stores carry many different brands that contain various combinations of 2,4- D, MCPA, MCPP, and dicamba, weed killers that control broadleaf weeds. First establish the identity of the weeds, then check product labels to determine which herbicide best controls the weeds you have. Then, be sure and follow label directions. Some weeds may require more than one application. Perennial weeds are best killed when they are actively growing, which is usually in spring and fall. Herbicides applied in the summer are usually less effective. 3. Shade out the weeds. Areas of weeds can also be killed by covering the affected areas with black plastic, felt paper, boards, or cardboard until the weeds are dead. This will kill all plants that are shaded, including both desirable and undesirable perennial grasses. This may take several weeks. The killed areas will need to be tilled and reseeded or sodded at a later date.[图片]

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Nimblewill, Muhlenbergia schreberi, is a warm-season perennial grass, which forms dense mats one or more feet in diameter in sun or shade. Patches look fuzzy, somewhat like a scouring pad, with a dull, blue-green tinge making them quite noticeable against the greener lawn grasses. Its stoloniferous growth pattern makes it resemble creeping bentgrass and Bermuda grass. Because it is a warm-season grass, patches of nimblewill appear as brown, dead spots early in the year and can be confused with actual dead spots. During the growing season its blue-green color and "fuzzy" faded appearance helps to differentiate it from other grasses. It is weakly attached to its roots and pulls up easily. It grows well in either sun or shade and often invades shady areas of turf where other more desirable grasses find it difficult to grow. [图片]Symptoms and Diagnosis Nimblewill has thin flat leaves with four veins on the upper surface; its leaves are usually less than 2 inches long and are blue-green. Leaves are rolled in the bud with a very short membranous ligule and only a few hairs near the ligule. The hard thin stems begin growing upright but later often lie flat on the ground near the base and become upright farther up the stem. It can be confused with creeping bentgrass which is finer in texture with narrow green leaves, a large, pointed ligule and no hairs around the ligule. Another look-a-like is Bermuda grass, which can be distinguished by its fringed ligule of fringed hairs. [图片]Life Cycle Nimblewill is a warm-season perennial grass, which flowers from August to October. It turns brown at the first frost and is very slow to green up in the spring. It spreads by seeds and spreading stems. [图片]Integrated Pest Management Strategies 1. Maintenance. Maintain a dense, healthy lawn through proper turf selection, establishment, and maintenance. Improve soil drainage, reduce shade and increase air movement. 2. Chemical control. Presently only one herbicide available to homeowners, Tenacity (active ingredient mesotrione), provides selective control of nimblewill in cool-season lawns such as Kentucky bluegrass, tall fescue, fine fescues and perennial ryegrass. Application rates can vary so follow label directions. It is not approved for use on warm-season grasses such as zoysia grass. Several applications are needed for good control and a non-ionic surfactant should be added to the mix. Nimblewill will become bleached and white as it dies. A cheaper control method is to apply a non-selective, post-emergent herbicide such as glyphosate (Roundup) to patches of nimblewill and then replant the areas. Apply the herbicide when the nimblewill is actively growing during the summer. Applying in late autumn to early spring when it is dormant will not provide control. Glyphosate, being a non-selective herbicide, will kill desirable lawn grasses as well. 3. Watering. Improve drainage as nimblewill thrives in poorly drained moist soil. [图片]Organic Strategies Strategies 1 and 4 are strictly organic approaches.

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Dodder is an annual seed-bearing parasitic vine in the dodder family (formerly placed in the morning-glory family). Its thin, thread-like, yellow or orange stems grow rapidly entwining and covering their host plants. Cuscate is the most common genus and is found throughout the US and Canada. Of the 50 species that occur, most are found in tropical and warm-temperate areas but some species also occur in cooler areas including St. Louis where they can grow from seed each year and infest herbaceous and small woody plants. Since seeds can be difficult to separate from some agricultural crops dodder has been spread widely through agriculture. [图片]Life Cycle Dodder seeds germinate in soil and can live on their own for 5 to 10 days until they are about a foot tall. If they have not found a suitable host by this time the seedlings will die. Seedlings that find a suitable host twine around the plant and insert haustoria (modified adventitious roots) into the tender stem. The haustoria penetrate and tap the plant's vascular system for water, minerals and nutrients. Plants are weakly photosynthetic, but most produce very little food on their own. They rely upon their host plant for survival. As the vine taps the host plant its connection to the soil is severed. Small, white, bell-shaped flowers form in late summer and early fall and can produce copious amounts of seed. Plants are annual and are killed by frost. Plants regrow from seed each year. [图片]Integrated Pest Management Strategies 1. Remove the plants. As soon as the thin vining stems of dodder are observed they should be gathered and removed before seed is set. Removal of the host plant is usually recommended. Complete eradication from the host plant is usually not possible. 2. Scout for and remove new seedlings as they appear. Monitor areas previously infested with dodder closely and pull young seedling before they attach themselves to new plants and certainly before they set seed. Seeds can survive in the soil for more than 20 years. 3. Treat with an herbicide. Dodder and the host plant can be killed by treating with glyphosate, a non-selective herbicide. As a follow-up measure to kill germinating seeds, treat soil with a preemergent herbicide such as Dacthal before seeds germinate in spring. [图片]Organic Strategies Strategies 1 and 2 are strictly organic approaches.

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Mosses are small, primitive plants that have reduced leaves and a mass of fine, thread-like stems. A mild, wet winter combined with turfgrass which is thin and weak offers an opportunity for moss and/or algae growth. Mosses are not parasitic on turfgrass. They produce their own food, grow where grass will not, and form a soft mat of growth, which makes a barrier, preventing grass from growing. Shady conditions and infertile and/or compacted, poorly drained soil encourage moss growth. [图片]Symptoms and Diagnosis Moss in the lawn is quite visible and can be annoying. Large areas void of grass may be covered by moss. These small primitive plants have reduced leaves and reproduce by spores, not seeds. [图片]Life Cycle Moss prefers to grow and become established in the winter with growth peaking in early, wet springs. If grass is established in the fall, moss will fail to compete for space in which to grow. This presents the best strategy for avoiding moss development. [图片]Integrated Pest Management Strategies 1. Cultural practices to inhibit moss growth and stimulate growth of desirable healthy lawn grass. A. Test soil for pH and nutrient content. If deficient in nutrients, follow recommendations of soil test. Fertilize with nitrogen just before the growth cycle. B. Improve drainage. In moist areas with poor drainage, add soil or contour the area to move water away from low lying areas. C. Increase light penetration. Trim lower branches of shade trees and thin to improve light penetration to the soil surface and improve air circulation. A ground cover may be used in lieu of grass if shade is too intense. D. Loosen compacted soils. Compacted soil should be tilled or core aerated to reduce compaction. Loosening the top 2 to 4 inches of soil will help. Cultivation breaks up the algae crust or moss mats. 2. Manual removal. Remove as much of the moss as possible by raking or dethatching. 3. Treatment.Treat the mossy areas with iron compounds; liquid ferric sulfate is the most effective. Fertilizers with iron compounds also work if very fine, near-dust formulations are used. Moss killers containing zinc sulfate will kill the moss but can also damage grass. Buy only products which state "for controlling moss in lawns" as some are for removal of moss in sidewalks and roofs and can be harmful to other plants. Lime and copper sulfate are ineffective in killing moss. 4. Turf selection. In shaded, well-drained soil, plant fine fescues. For shaded, moist areas, plant rough bluegrass. Neither grass, however, will survive extremely heavy shade or soil saturated for long periods. 5. Watering. Keep grass in good condition in the summer by watering deeply to establish deep roots. If an automatic watering system is used, water plentifully once or twice a week (1 inch per watering). [图片]Organic Strategies Strategies 1.B, 1.C, 1.D, 2, 4, and 5 are strictly organic approaches. Strategy 1.A could be considered an organic approach if an organic fertilizer is used.

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Crabgrass is an annual grassy lawn weed that spreads along the ground creating a dense mat that smothers desirable grasses. It was introduced from Eurasia and is widespread throughout the United States. [图片]Symptoms and Diagnosis There are three crabgrass species commonly found as weeds in lawns - hairy crabgrass (Digitaria sanguinalis), southern crabgrass (Digitaria ciliaris) and smooth crabgrass (Digitaria ischaemum). All three species are pale green, have a prostrate or ascending growth habit, and have flat 5-10 mm wide blades. The seed heads have 2-6 branches with 2 rows of seeds along each branch. Crabgrass may be found in a wide variety of landscape settings but grows best in full sun. Life Cycle Crabgrass is a warm season annual grass that overwinters as seeds and germinates when soil temperatures in mid spring consistently remain at 50 to 55 degrees for a number of days in a row. Seeds can continue to germinate throughout the summer if soil temperatures and moisture conditions are adequate. It grows during the heat of summer, sets seeds and is killed by the first frost. [图片]Integrated Pest Management Strategies 1. Practice good cultural techniques to keep lawns healthy and free of drought, nutritional or injury-induced stress. Cool season grasses fertilized in the fall and mid to late spring will go into mid-summer dormancy later and will compete better with the crabgrass. 2. Set the lawnmower at 3 inches high. Taller grass will shade the soil and decrease the germination rate of crabgrass seeds. 3. Pull crabgrass plants before they set seed. One plant can produce 150,000 seeds. 4. Overseed existing cool season lawns in the fall. A thick turf in the spring will shade the lawn, retard seed germination and better compete with any germinating weed plants. 5. Apply corn gluten meal herbicide about two to three weeks before crabgrass seeds begin to germinate. In Missouri, this would be between mid March to mid April or about the time when forsythia first begins to bloom. Corn gluten will inhibit the germination of turf grass seeds and should not be used within six weeks of reseeding a lawn. Corn gluten is only about 65% effective compared to synthetic products but is an organic control. 6. Apply a pre-emergent crabgrass herbicide about two weeks before crabgrass seeds begin to germinate. In mid-Missouri, this would be between mid March to mid April or about the time when forsythia first begins to bloom. Applying a pre-emergent herbicide after the crabgrass has begun to germinate will not provide good control but may inhibit seedlings at the 2-leaf stage or seeds that are slower to germinate. Products that combine pre-emergent herbicides and fertilizer are not recommended. Read and follow label directions carefully. 7. Apply a post-emergent crabgrass herbicide if a pre-emergent herbicide was not used or if it was ineffective and control is warranted in early summer. Read and follow label directions carefully. 8. Do nothing in late summer. Crabgrass is an annual grass that will be killed by frost. Applying a post-emergent herbicide in late summer may not be warranted as the first frost will kill it. Next year apply a pre-emergent in early spring to prevent new seedlings. [图片]Organic Strategies Strategies 1 - 5 are strictly organic approaches.

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Bamboos are divided into clumpers or runners, which can have a major impact on how well behaved they will be in your garden. [图片]Clumping bamboos Clumping types have a very short rhizomatous root structure and are incapable of expanding more than a few inches a year and will generally form discrete clumps. The clumps slowly enlarge as new culms emerge every year, and may require anywhere from 2-10 feet or more of space in order to reach their mature height, depending on species. Except for species of the genus Fargesia, the clumpers tend to be less cold-hardy than runners. Clumping bamboos generally do not require control. They may be shaped by removing new shoots at soil level when they begin to encroach more closely on nearby structures. [图片]Running bamboos Running types spread by sending out underground runners, or rhizomes, which sometimes emerge far from the parent plant. Runners fill in the spaces between plantings faster, making them ideal for screens, hedges, and the popular open grove look. Runners may be contained, as described below, since the rhizomes grow sideways at a depth of about 2-18 inches. Many are cold-hardy. Following are some strategies you can try for containing and eradicating running bamboos. [图片]Integrated Pest Management Strategies 1. Contain the running bamboo with a physical barrier. The safest containment methods for running bamboo are 1) Planting in containers, or 2) Installing a vertical 30-40 mil thick plastic rhizome barrier 22-30 inches deep around the perimeter of the area in which the bamboo is to be contained. The advantage of this material is that even large plantings of bamboo can be surrounded with a single length of plastic, requiring only one seam. It is preferable to cement (which often develops cracks), or metal (which rusts and requires many seams), is less expensive, and lasts 20-30 years if installed properly. Please refer to The American Bamboo Society for detailed installation instructions. 2. Cut off unwanted shoots. The active growth period usually lasts for only about 2 weeks every spring, then little or no additional new growth will occur until the following spring. Therefore, cut off any shoots you don’t want but remember all of the culms (stalks) of bamboo in a clump or grove are interconnected underground by rhizomes (underground stems). New shoots will grow again next year. If the bamboo in your yard comes from another’s yard, separate your grove from his by cutting the connecting rhizomes, which are usually quite shallow. If this isn’t done, and his part is healthy and vigorous, the rhizomes in your part will still be supported by the photosynthesis in the leaves of his part, and your efforts will be in vain. Cutting rhizomes with a spade or a saw will do the trick if it is done every year. If the growth is old, you may need to use a mattock or a digging bar the first time. Digging a ditch and putting in a barrier is a more permanent solution. 3. Mow unwanted shoots in lawn areas. If the bamboo is surrounded by lawn, then just mow frequently over the area where the bamboo is coming up during the spring shooting season. 4. Many years of effort may be needed to eradicate running bamboo. Begin by either digging as much of the root system out as possible – no easy job – or cutting the bamboo to the ground and then continue by following up with regular removal. New shoots will come up from the rhizomes. Break them off or cut them off with pruning shears. Keep doing this until no more shoots come up. This will exhaust the energy stored in the rhizomes underground. Without green leaves to photosynthesize and produce new energy, they will no longer be able to send up new shoots. The rhizomes will be left behind, but will rot away. This is a slow, labor intensive process. 5. Using chemical weed killers may be helpful. Be warned bamboo doesn't respond well to any herbicide currently on the market. If glyphosate (Round Up) is used, remember it is taken in through the leaves only, and it must be applied in an undiluted form. Often the plants will still re-shoot. Some have used a “cut and paste method” with some success. Each culm is cut to within 6” of the ground and immediately (within 15 seconds) painted with concentrated glyphosate. It has been noted that imazapyr (Arsenal) is more effective on bamboo than glyphosate. However, imazapyr has a great deal of foliar and soil activity and can be very harmful to nearby hardwood trees, shrubs, and all grasses if their roots extend into the vicinity of the application. Therefore, if the bamboo is growing near any desirable plant species, imazapyr should not be used. Glyphosate does not have soil activity and will only kill plants that are contacted with the spray solution. This makes glyphosate a more useful herbicide option for most areas where bamboo grows. It is important to note that one application of glyphosate will not eradicate bamboo. It will most likely be necessary to mow and spray as many as 4 times for complete bamboo control to be achieved. Persistence is key when targeting running bamboo. [图片]Organic Strategies Strategies 1, 2, 3, and 4 are strictly organic approaches.

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#牡丹扁刺蛾 分布与危害 分布广泛在黑龙江、吉林、辽宁、河北、安徽等。是牡丹的主要害虫之一。 主要是2龄和3龄幼虫为害，2龄幼虫食叶肉，3龄后幼虫咬食叶表皮，导致叶片成穿孔，5龄后大量蚕食叶片，为害严重，影响树势及观赏。体有毒毛，接触人后有刺痛感或红肿现象。 形态特征 成虫 雄蛾体长12-18毫米，翅展30-40毫米，雄虫35-45毫米。头、胸、腹基部白色微带黄色。腹部其余部分和肛毛簇黄色，触角干白色，前翅后缘有2个褐色斑，有的个体内侧的1个褐色斑不明显。前后翅反面亦白色。前翅前缘黑褐色。腹末有橙黄色毛。 卵 扁圆形，初为黄绿色，后变为暗褐色，长约1.1毫米。 幼虫 体长22-35毫米，扁平椭圆形，背稍隆起。每体节有4个绿色枝状毒刺，其中虫体两侧边缘的1对较大，亚背线上的1对较小。中背线灰白色，体背中央两侧各有一个明显的红点。 蛹 匿于茧中，长椭圆形，灰白色，羽化前转褐色。 茧 长14-15毫米，钙质，硬且脆，灰褐色。 发生规律 华北年生2代，主要是以3龄幼虫在树皮缝隙或枯枝落叶层内越冬。翌年4月底开始为害嫩芽，6月中旬化蛹，6月下旬成虫羽化，7月下旬-8月初第二代成虫出现，10月初进入越冬期。成虫在夜间活动，一般将卵产在叶背或枝干上。卵块表面被黄毛。幼虫孵化后，群集叶背取食，2龄后分散为害，越冬幼虫有群居性。 防治方法 （1）保护和利用天敌。有小茧蜂、上海青蜂等天敌。 （2）在冬季和早春刮除缝隙中的越冬幼虫，清除枯枝落叶，将其烧毁或深埋。减少虫源。 （3）化学防治：尽量选择在低龄幼虫期防治。此时虫口密度小，危害小，且虫的抗药性相对较弱。防治时用45%丙溴辛硫磷（国光依它）1000倍液，或国光乙刻（20%氰戊菊酯）1500倍液+乐克（5.7%甲维盐）2000倍混合液,40%啶虫.毒（必治）1500-2000倍液喷杀幼虫，可连用1-2次，间隔7-10天。可轮换用药，以延缓抗性的产生。