文章
Dummer. ゛☀
2017年07月30日
Family - Asteraceae
Stems - Stout, erect, herbaceous, to +2.5m tall, branching in the apical 1/2, single or multiple from the base, green but often purplish in strong sun, terete to slightly 4-angled (the angles rounded), villosulous to villous. The hairs of the stem with pustulate bases which create a slightly scabrous feel to the stem.
Leaves - Opposite, decussate, sessile, ovate, acute to acuminate, to +15cm long, +9cm broad, entire or with coarse shallow teeth (the teeth with minute whitish apices), scabrous above, sericeous below. Hairs on the upper surface of the leaves with pustulate bases, those of the lower surface pilosulose. Veins around the base of the blade impressed adaxially, expressed abaxially.
Inflorescence - Terminal cymose arrangement of flower heads on stems. Each division of the inflorescence subtended by a pair of reduced foliaceous bracts. Peduncles villosulous, with multicellular trichomes.
Involucre - To 2.5cm broad, +1.5cm tall (long). Phyllaries imbricate, not tightly appressed, broadly ovate to orbicular, acute to slightly acuminate, to 1.5cm long and broad, green, glandular pubescent and with some antrorse appressed hairs at the base externally, glandular and antrorse appressed pubescent in the apical half internally (glabrous basally), with ciliolate margins.
Ray flowers - +/-15 per flower head, fertile, pistillate. Ligule yellow, +3cm long, +7mm broad, with two adaxial vertical grooves, with a single notch at the apex, sparsely pubescent at the base. Corolla tube to 3mm long, pilose, pale yellow. Style yellowish-brown, divided to below the middle, glabrous, +/-7mm long. Achenes compressed, orbicular to broadly ovate, +/-7mm in diameter in flower, retrorse appressed pubescent, with two basal projections. Projections pointed, to 2-3mm long.
Disk flowers - Disk +2cm broad. Flowers staminate. Corolla tube yellow, 8-9mm long, contracted in the basal 1/5, white at the base, glabrous basally, with some pubescence at the apex, glabrous internally, 5-lobed. Lobes triangular, acute, +/-1mm long, erect. Stamens 5, adnate at the apex of the contracted portion of the corolla tube. Filaments yellow, -2mm long. Anthers brown, 5mm long, partially exserted, connivent around the style. Style yellow (pale in basal 1/2), to +1.5cm long, glabrous in the basal 1/2, pubescent apically, undivided. Achene white in flower, terete, with retrorse hairs, 6mm long, -1mm in diameter, tapered to the apex. Receptacle small, mostly flat or slightly convex. Chaff partially enclosing the achenes, +/-1.5cm long, -2mm broad, white in the basal 2/3, green apically, glabrous internally, pubescent (ciliate) externally at least on the midrib and at the apex, glabrous at the base.
Flowering - July - September.
Habitat - Rocky and dry open woods, prairies, glades.
Origin - Native to U.S.
Other info. - This big species can be found throughout Missouri. The plant is variable in stem and involucre pubescence but despite this, it is still an easy species to ID in the field. The broad rounded phyllaries and undivided styles are good characteristics for proper identification.
Steyermark breaks the species up into two varieties based on stem pubescence. Variety laeve T. & G. has glabrous and glaucous stems and involucres. Variety integrifolium has pubescent stems and involucres. This latter variety is much more common in the state.
Stems - Stout, erect, herbaceous, to +2.5m tall, branching in the apical 1/2, single or multiple from the base, green but often purplish in strong sun, terete to slightly 4-angled (the angles rounded), villosulous to villous. The hairs of the stem with pustulate bases which create a slightly scabrous feel to the stem.
Leaves - Opposite, decussate, sessile, ovate, acute to acuminate, to +15cm long, +9cm broad, entire or with coarse shallow teeth (the teeth with minute whitish apices), scabrous above, sericeous below. Hairs on the upper surface of the leaves with pustulate bases, those of the lower surface pilosulose. Veins around the base of the blade impressed adaxially, expressed abaxially.
Inflorescence - Terminal cymose arrangement of flower heads on stems. Each division of the inflorescence subtended by a pair of reduced foliaceous bracts. Peduncles villosulous, with multicellular trichomes.
Involucre - To 2.5cm broad, +1.5cm tall (long). Phyllaries imbricate, not tightly appressed, broadly ovate to orbicular, acute to slightly acuminate, to 1.5cm long and broad, green, glandular pubescent and with some antrorse appressed hairs at the base externally, glandular and antrorse appressed pubescent in the apical half internally (glabrous basally), with ciliolate margins.
Ray flowers - +/-15 per flower head, fertile, pistillate. Ligule yellow, +3cm long, +7mm broad, with two adaxial vertical grooves, with a single notch at the apex, sparsely pubescent at the base. Corolla tube to 3mm long, pilose, pale yellow. Style yellowish-brown, divided to below the middle, glabrous, +/-7mm long. Achenes compressed, orbicular to broadly ovate, +/-7mm in diameter in flower, retrorse appressed pubescent, with two basal projections. Projections pointed, to 2-3mm long.
Disk flowers - Disk +2cm broad. Flowers staminate. Corolla tube yellow, 8-9mm long, contracted in the basal 1/5, white at the base, glabrous basally, with some pubescence at the apex, glabrous internally, 5-lobed. Lobes triangular, acute, +/-1mm long, erect. Stamens 5, adnate at the apex of the contracted portion of the corolla tube. Filaments yellow, -2mm long. Anthers brown, 5mm long, partially exserted, connivent around the style. Style yellow (pale in basal 1/2), to +1.5cm long, glabrous in the basal 1/2, pubescent apically, undivided. Achene white in flower, terete, with retrorse hairs, 6mm long, -1mm in diameter, tapered to the apex. Receptacle small, mostly flat or slightly convex. Chaff partially enclosing the achenes, +/-1.5cm long, -2mm broad, white in the basal 2/3, green apically, glabrous internally, pubescent (ciliate) externally at least on the midrib and at the apex, glabrous at the base.
Flowering - July - September.
Habitat - Rocky and dry open woods, prairies, glades.
Origin - Native to U.S.
Other info. - This big species can be found throughout Missouri. The plant is variable in stem and involucre pubescence but despite this, it is still an easy species to ID in the field. The broad rounded phyllaries and undivided styles are good characteristics for proper identification.
Steyermark breaks the species up into two varieties based on stem pubescence. Variety laeve T. & G. has glabrous and glaucous stems and involucres. Variety integrifolium has pubescent stems and involucres. This latter variety is much more common in the state.
0
0
文章
Dummer. ゛☀
2017年07月30日
Family - Asteraceae
Stems - To 2m tall, from a short woody caudex and thickened roots, herbaceous, erect, glabrous, glaucous, branching in apical 1/2, fistulose, single from the base.
Leaves - Opposite, decussate, petiolate, trifoliolate. Petioles glabrous, to 2cm long. Bases of opposing petioles connected and enveloping the stem. Lateral leaflets sessile. Terminal leaflet with a short petiolule (to 5mm long). Leaflets entire, pubescent abaxially, very sparse pubescent adaxially, acute, oblong-lanceolate to lanceolate, to 11cm long, 3.5cm broad. Venation is tuberculate adaxially and plainly visible below. Margins thickened and antrorse strigillose.
Inflorescence - A flat-topped cymose arrangement of flower heads.
Involucre - Biseriate, to 6mm tall (long), 7mm in diameter. Outer phyllaries green and linear, +/-6 in number, very sparse pubescent, +/-5mm long, 1mm broad, rounded at apex. Inner phyllaries broad, green at base, yellow in apical 1/2, pubescent externally, glabrous internally, the apices bent and spreading outward, acute, 7-8mm long, 3-4mm broad.
Ray flowers - Sterile, typically 8 per flower head. Ligules yellow, to +/-3cm long, to 1cm broad, glabrous or with very few hairs near base by the corolla tube. Achene compressed, to 3.5mm long in flower, yellowish, mostly glabrous but with some pubescence at apex. Pappus of short eros scales.
Disk flowers - Disk to -1cm broad. Corolla 5mm long, contracted at base for about 1mm, dark purple at apex, 5-lobed. LObes acute, triangular, spreading to recurved, +/-.8mm long. Stamens 5, adnate at apex of contracted portion of corolla tube. Filaments white, glabrous, compressed, 2.1mm long, with an obvious midvein. Anthers purple, to 2.3mm long, connate around the style, partially exserted. Style glabrous, pale yellow, slightly swollen at base, bifurcate, purple in apical portion (stigmas). Achenes compressed, greenish-white in flower, glabrous, 3mm long. Pappus of short eros scales. Receptacle flat. Chaff thin, glabrous, golden at the apex, 7-8mm long, .3mm broad.
Flowering - July - September.
Habitat - Prairies, rocky open woods, bluffs, thickets, roadsides, railroads.
Origin - Native to U.S.
Other info. - This tall species of Coreopsis is found throughout Missouri except in a few counties in the "bootheel." The plant is tolerant of dry conditions and would make a good garden specimen. This plant is easy to ID in the field because of its glabrous, glaucous stems and its trifoliolate leaves. Occasionally a small plant will have leaves which are undivided.
Stems - To 2m tall, from a short woody caudex and thickened roots, herbaceous, erect, glabrous, glaucous, branching in apical 1/2, fistulose, single from the base.
Leaves - Opposite, decussate, petiolate, trifoliolate. Petioles glabrous, to 2cm long. Bases of opposing petioles connected and enveloping the stem. Lateral leaflets sessile. Terminal leaflet with a short petiolule (to 5mm long). Leaflets entire, pubescent abaxially, very sparse pubescent adaxially, acute, oblong-lanceolate to lanceolate, to 11cm long, 3.5cm broad. Venation is tuberculate adaxially and plainly visible below. Margins thickened and antrorse strigillose.
Inflorescence - A flat-topped cymose arrangement of flower heads.
Involucre - Biseriate, to 6mm tall (long), 7mm in diameter. Outer phyllaries green and linear, +/-6 in number, very sparse pubescent, +/-5mm long, 1mm broad, rounded at apex. Inner phyllaries broad, green at base, yellow in apical 1/2, pubescent externally, glabrous internally, the apices bent and spreading outward, acute, 7-8mm long, 3-4mm broad.
Ray flowers - Sterile, typically 8 per flower head. Ligules yellow, to +/-3cm long, to 1cm broad, glabrous or with very few hairs near base by the corolla tube. Achene compressed, to 3.5mm long in flower, yellowish, mostly glabrous but with some pubescence at apex. Pappus of short eros scales.
Disk flowers - Disk to -1cm broad. Corolla 5mm long, contracted at base for about 1mm, dark purple at apex, 5-lobed. LObes acute, triangular, spreading to recurved, +/-.8mm long. Stamens 5, adnate at apex of contracted portion of corolla tube. Filaments white, glabrous, compressed, 2.1mm long, with an obvious midvein. Anthers purple, to 2.3mm long, connate around the style, partially exserted. Style glabrous, pale yellow, slightly swollen at base, bifurcate, purple in apical portion (stigmas). Achenes compressed, greenish-white in flower, glabrous, 3mm long. Pappus of short eros scales. Receptacle flat. Chaff thin, glabrous, golden at the apex, 7-8mm long, .3mm broad.
Flowering - July - September.
Habitat - Prairies, rocky open woods, bluffs, thickets, roadsides, railroads.
Origin - Native to U.S.
Other info. - This tall species of Coreopsis is found throughout Missouri except in a few counties in the "bootheel." The plant is tolerant of dry conditions and would make a good garden specimen. This plant is easy to ID in the field because of its glabrous, glaucous stems and its trifoliolate leaves. Occasionally a small plant will have leaves which are undivided.
0
0
文章
Dummer. ゛☀
2017年07月30日
Family - Asteraceae
Stems - To 1m tall, erect, with fibrous roots, multiple from base, branching in apical 1/2, hirsute, slightly scabrous, herbaceous. Hairs of the stem multicellular.
Leaves - Opposite, petiolate. Petioles to +/-1.5cm long, hirsute, minutely winged with decurrent leaf tissue. Blades ovate-lanceolate, entire, acuminate, to +/-8cm long, +/-3.5cm broad, pubescent abaxially (slightly scabrous), mostly glabrous adaxially, lighter green abaxially, often with two small lateral lobes at base.
Inflorescence - Single flower heads terminating long peduncles. Peduncles to +15cm long, pubescent near base, glabrous near apex.
Involucre - Phyllaries in two series. Outer phyllaries 8, green, subulate to lanceolate, to 7mm long, 1.7mm broad, spreading, glabrous, with scarious margins, with some short cilia at apex. Inner phyllaries yellow-green, erect and spreading in apical 1/2, lanceolate, 9mm long, +/-3mm broad, glabrous.
Ray flowers - Typically 8 per flower head, sterile. Ligules to 1.5cm long, 8-9mm broad, glabrous, distinctly notched or lobed at apex. Achenes (in flower) 1.3mm long, .9mm broad, compressed, white. Pappus absent.
Disk flowers - Disk 6-8mm broad. Flowers yellow, 5-lobed. Corolla tube 4mm long, glabrous. Achenes with two small scales as pappus, compressed, glabrous, winged, tuberculate, 2.5-3mm long in fruit, black when mature, greenish-white in flower. Receptacle convex. Chaff 6mm long, compressed, whitish at base, becoming thin and yellow at apex.
Flowering - May - October.
Habitat - Rocky open woods, base of wooded bluffs, low ground, gravel stream beds, alluvial thickets, railroads.
Origin - Native to U.S.
Other info. - This species can be found mainly in the lower 1/2 of Missouri. A small population also occurs in the northeast corner of the state. This plant can be easy to ID because of its pubescent stems and leaves, distinctive leaf shape, and deeply notched ray ligules. The plant does well in cultivation and grows well from seed.
Stems - To 1m tall, erect, with fibrous roots, multiple from base, branching in apical 1/2, hirsute, slightly scabrous, herbaceous. Hairs of the stem multicellular.
Leaves - Opposite, petiolate. Petioles to +/-1.5cm long, hirsute, minutely winged with decurrent leaf tissue. Blades ovate-lanceolate, entire, acuminate, to +/-8cm long, +/-3.5cm broad, pubescent abaxially (slightly scabrous), mostly glabrous adaxially, lighter green abaxially, often with two small lateral lobes at base.
Inflorescence - Single flower heads terminating long peduncles. Peduncles to +15cm long, pubescent near base, glabrous near apex.
Involucre - Phyllaries in two series. Outer phyllaries 8, green, subulate to lanceolate, to 7mm long, 1.7mm broad, spreading, glabrous, with scarious margins, with some short cilia at apex. Inner phyllaries yellow-green, erect and spreading in apical 1/2, lanceolate, 9mm long, +/-3mm broad, glabrous.
Ray flowers - Typically 8 per flower head, sterile. Ligules to 1.5cm long, 8-9mm broad, glabrous, distinctly notched or lobed at apex. Achenes (in flower) 1.3mm long, .9mm broad, compressed, white. Pappus absent.
Disk flowers - Disk 6-8mm broad. Flowers yellow, 5-lobed. Corolla tube 4mm long, glabrous. Achenes with two small scales as pappus, compressed, glabrous, winged, tuberculate, 2.5-3mm long in fruit, black when mature, greenish-white in flower. Receptacle convex. Chaff 6mm long, compressed, whitish at base, becoming thin and yellow at apex.
Flowering - May - October.
Habitat - Rocky open woods, base of wooded bluffs, low ground, gravel stream beds, alluvial thickets, railroads.
Origin - Native to U.S.
Other info. - This species can be found mainly in the lower 1/2 of Missouri. A small population also occurs in the northeast corner of the state. This plant can be easy to ID because of its pubescent stems and leaves, distinctive leaf shape, and deeply notched ray ligules. The plant does well in cultivation and grows well from seed.
0
0
文章
Dummer. ゛☀
2017年07月30日
Family - Asteraceae
Stems - From a small crown and rhizomes, single or multiple from the base, herbaceous, erect, to -1m tall, simple to branching, green with light green vertical striations, somewhat carinate or not, somewhat angled in the upper 1/2, mostly glabrous or with a few hairs at the nodes, +/-3mm in diameter.
Leaves - Opposite, sessile, decussate, 3-5-lobed in the apical 1/2, shaped like a turkey foot, deep green above and below, sometimes with light green around the midvein abaxially, to +/-6cm long, antrorse strigillose above and below and on margins. Lobes 3-6mm broad, entire, typically with a minute whitish tip (use a lens to see). The central lobe typically longer than the lateral lobes. All the main veins of the leaf coming from the very base of the leaf. Leaves reduced to bracts in the inflorescence.
Inflorescence - Single pedunculate flower head terminating each stem. Some flowers axillary from the upper leaf axils. Peduncle typically naked, glabrous, slightly expanded just below the involucre.
Involucre - Biseriate. Outer series of +/-12 phyllaries. Phyllaries subulate-linear, entire, ascending, 6-7mm long, 2mm broad, rounded at the apex, with sparse strigose-ciliate margins. Inner phyllaries yellow-brown, bent outward in the apical 1/3, glabrous, 4-5mm broad, 7-9mm long, oblanceolate to spatulate, rounded to subacute at apex, with brown vertical striations, green at base.
Ray flowers - Sterile, 8-10 per flower head. Ligule yellow, 2-3cm long, +/-1cm broad, mostly glabrous or with a few hairs on the veins below, with 2 impressed veins near the base, 3-toothed at the apex, elliptic-oblong. Corolla tube greenish, +/-3mm long, with sparse multicellular trichomes. The trichomes pilosulous. Achenes compressed, brown at maturity, glabrous, with scarious margins, truncate apically and basally, to 5mm long. Pappus none.
Disk flowers - Disk -1cm broad. Corolla tube 5mm long, yellow, 5-lobed, constricted at the base and opaque, expanded in the apical 1/2 and translucent yellow, with a few multicellular trichomes at the apex of the constriction. Apical 1/2 with 5 brown vertical nerves. Lobes erect, acute, -1mm long. Stamens 5, adnate at the base of the expanded portion of the corolla tube. Filaments yellow, glabrous, +2mm long, with a visible midvein, slightly compressed. Anthers brown-purple, 2-2.2mm long, partially exserted, connate around the style. Style bifurcate, exserted beyond the anthers, yellow in the apical 1/2, white basally, glabrous. Stigmas short, yellow, broadly lanceolate, +/-1mm long. Achenes as in the ray flowers but often thinner. Pappus none. Receptacle flat. Chaff linear, translucent, 7-9mm long, with brown vertical striations, slightly expanded at the apex, .3mm broad or less.
Flowering - May - July.
Habitat - Prairies, glades, fallow fields, rocky open woods, thickets, roadsides.
Origin - Native to U.S.
Other info. - This striking species is a common roadside plant in the Ozarks in early summer. It is usually on of the first members of its genus to bloom. The plant is easy to ID in the field because of its parted, opposite leaves. It would make an easy garden subject and should be cultivated more.
Stems - From a small crown and rhizomes, single or multiple from the base, herbaceous, erect, to -1m tall, simple to branching, green with light green vertical striations, somewhat carinate or not, somewhat angled in the upper 1/2, mostly glabrous or with a few hairs at the nodes, +/-3mm in diameter.
Leaves - Opposite, sessile, decussate, 3-5-lobed in the apical 1/2, shaped like a turkey foot, deep green above and below, sometimes with light green around the midvein abaxially, to +/-6cm long, antrorse strigillose above and below and on margins. Lobes 3-6mm broad, entire, typically with a minute whitish tip (use a lens to see). The central lobe typically longer than the lateral lobes. All the main veins of the leaf coming from the very base of the leaf. Leaves reduced to bracts in the inflorescence.
Inflorescence - Single pedunculate flower head terminating each stem. Some flowers axillary from the upper leaf axils. Peduncle typically naked, glabrous, slightly expanded just below the involucre.
Involucre - Biseriate. Outer series of +/-12 phyllaries. Phyllaries subulate-linear, entire, ascending, 6-7mm long, 2mm broad, rounded at the apex, with sparse strigose-ciliate margins. Inner phyllaries yellow-brown, bent outward in the apical 1/3, glabrous, 4-5mm broad, 7-9mm long, oblanceolate to spatulate, rounded to subacute at apex, with brown vertical striations, green at base.
Ray flowers - Sterile, 8-10 per flower head. Ligule yellow, 2-3cm long, +/-1cm broad, mostly glabrous or with a few hairs on the veins below, with 2 impressed veins near the base, 3-toothed at the apex, elliptic-oblong. Corolla tube greenish, +/-3mm long, with sparse multicellular trichomes. The trichomes pilosulous. Achenes compressed, brown at maturity, glabrous, with scarious margins, truncate apically and basally, to 5mm long. Pappus none.
Disk flowers - Disk -1cm broad. Corolla tube 5mm long, yellow, 5-lobed, constricted at the base and opaque, expanded in the apical 1/2 and translucent yellow, with a few multicellular trichomes at the apex of the constriction. Apical 1/2 with 5 brown vertical nerves. Lobes erect, acute, -1mm long. Stamens 5, adnate at the base of the expanded portion of the corolla tube. Filaments yellow, glabrous, +2mm long, with a visible midvein, slightly compressed. Anthers brown-purple, 2-2.2mm long, partially exserted, connate around the style. Style bifurcate, exserted beyond the anthers, yellow in the apical 1/2, white basally, glabrous. Stigmas short, yellow, broadly lanceolate, +/-1mm long. Achenes as in the ray flowers but often thinner. Pappus none. Receptacle flat. Chaff linear, translucent, 7-9mm long, with brown vertical striations, slightly expanded at the apex, .3mm broad or less.
Flowering - May - July.
Habitat - Prairies, glades, fallow fields, rocky open woods, thickets, roadsides.
Origin - Native to U.S.
Other info. - This striking species is a common roadside plant in the Ozarks in early summer. It is usually on of the first members of its genus to bloom. The plant is easy to ID in the field because of its parted, opposite leaves. It would make an easy garden subject and should be cultivated more.
0
0
文章
Dummer. ゛☀
2017年07月29日
Family - Asteraceae
Stems - To +70cm tall, herbaceous, erect, glabrous, 4-angled, dichotomously branching, from taproot.
Leaves - Opposite, petiolate, deeply bipinnatifid, glabrous or with a few sparse hairs, to +/-20cm long, +/-12cm broad. Petiole to 10cm long, slightly winged. Ultimate divisions acute to acuminate.
Inflorescence - Single axillary pedunculate flower head. Peduncles elongating in fruit to -10cm long, glabrous or sparse puberulent.
Involucre - 3mm in diameter, -5mm tall (long). Phyllaries deep green, spatulate to oblanceolate or subulate, to 6mm long, acute, unequal, sparse appressed pubescent externally, glabrous internally, with strigillose margins. Some phyllaries with slightly scarious or lighter-colored margins.
Ray flowers - Sterile. Ligule yellow, 2-5 in number (sometimes absent), 4.5mm long, 2mm broad, spatulate, rounded at apex, glabrous. Achene compressed, 1mm long, glabrous. Pappus absent.
Disk flowers - Typically +/-10 in number, fertile. Corolla tube 3mm long, 5-lobed, glabrous, orange, near and at apex. Lobes acute, .5mm long, glabrous. Stamens 5, adnate near base of corolla tube. Anthers connate around style, included, reddish, 1.1mm long. Style bifurcate, barely exserted, yellow. Achene (in flower) 2mm long, glabrous, 4-angled. Pappus 4 retrorse barbellate awns to 2.5mm long. Achenes in fruit to 1.3cm long, blackish-green, typically unequal, with persistent pappus. Receptacle flat. Chaff to 4mm long, 1mm broad, scarious, greenish, glabrous.
Flowering - August - October.
Habitat - Open woods, glades, pastures, open rocky ground, thickets, waste ground, roadsides, railroads.
Origin - Native to U.S., and tropical regions around the globe.
Other info. - The genus name Bidens means "two teeth", referring to the awns of the pappus and fruit (other species only have two awns). Because of the awns, the fruits will cling to most anything, thus distributing the plant quickly to new locations. The plant is not stout and wilts when hit with direct hot sun. Ray ligules are not always present in the flower heads.
Stems - To +70cm tall, herbaceous, erect, glabrous, 4-angled, dichotomously branching, from taproot.
Leaves - Opposite, petiolate, deeply bipinnatifid, glabrous or with a few sparse hairs, to +/-20cm long, +/-12cm broad. Petiole to 10cm long, slightly winged. Ultimate divisions acute to acuminate.
Inflorescence - Single axillary pedunculate flower head. Peduncles elongating in fruit to -10cm long, glabrous or sparse puberulent.
Involucre - 3mm in diameter, -5mm tall (long). Phyllaries deep green, spatulate to oblanceolate or subulate, to 6mm long, acute, unequal, sparse appressed pubescent externally, glabrous internally, with strigillose margins. Some phyllaries with slightly scarious or lighter-colored margins.
Ray flowers - Sterile. Ligule yellow, 2-5 in number (sometimes absent), 4.5mm long, 2mm broad, spatulate, rounded at apex, glabrous. Achene compressed, 1mm long, glabrous. Pappus absent.
Disk flowers - Typically +/-10 in number, fertile. Corolla tube 3mm long, 5-lobed, glabrous, orange, near and at apex. Lobes acute, .5mm long, glabrous. Stamens 5, adnate near base of corolla tube. Anthers connate around style, included, reddish, 1.1mm long. Style bifurcate, barely exserted, yellow. Achene (in flower) 2mm long, glabrous, 4-angled. Pappus 4 retrorse barbellate awns to 2.5mm long. Achenes in fruit to 1.3cm long, blackish-green, typically unequal, with persistent pappus. Receptacle flat. Chaff to 4mm long, 1mm broad, scarious, greenish, glabrous.
Flowering - August - October.
Habitat - Open woods, glades, pastures, open rocky ground, thickets, waste ground, roadsides, railroads.
Origin - Native to U.S., and tropical regions around the globe.
Other info. - The genus name Bidens means "two teeth", referring to the awns of the pappus and fruit (other species only have two awns). Because of the awns, the fruits will cling to most anything, thus distributing the plant quickly to new locations. The plant is not stout and wilts when hit with direct hot sun. Ray ligules are not always present in the flower heads.
0
0
文章
Dummer. ゛☀
2017年07月28日
Family - Convolvulaceae
Stems - Vining, twining, herbaceous, to many meters long, with a combination of long and short pubescence (the hairs mostly retrorse, the longest with pustulose bases), mostly terete.
Leaves - Alternate, petiolate. Petioles to +12cm long, pubescent as the stem, with a shallow adaxial groove. Blades typically 3-lobed but simple also, pubescent above and below, to 15cm broad and long. Lobes typically acuminate and entire.
Inflorescence - Axillary pedunculate clusters(cymes) of typically 3 flowers. Peduncles to 6cm long, pubescent as the stem, often purple at the base. Pedicels short, 3-5mm long, retrorse pubescent (the hairs short). Each division of the inflorescence subtended by opposite linear-attenuate bracts. Bracts to -3cm long, 2-3mm broad, spreading pubescent, reduced upwards.
Flowers - Corolla blue, funnelform, to +3.5cm long, 5cm broad, glabrous internally and externally. Stamens 5, included, adnate near the base of the corolla tube. Filaments white, to 1.5cm long, mostly glabrous but with distinct thickened hairs at the base. Anthers white, 2mm long, 1.5mm broad. Ovary superior, white, glabrous, subtended by white nectariferous ring, 1.5mm in diameter, conic, 3-locular. Placentation axile. Seeds 6. Style white, glabrous, included, 1.6cm long. Stigma biglobose, 2mm in diameter. Sepals 5, long-aristate, expanded at base for 6-7mm, 2.5cm long in flower, longer in fruit, glabrous internally. Basal portion with dense long spreading hairs. Arista short pubescent.
Flowering - June - October.
Habitat - Waste ground, disturbed sites, thickets, roadsides, railroads.
Origin - Native to Central and South America.
Other info. - This is an attractive vine but it can be tough to get rid of once established. This species frequently occurs in flower beds and cultivated areas. The flowers only last one day before wilting. Because this species is found throughout the world there is some confusion about it's origin. Most tend to agree the plant is from the American tropics.
The typical variety found is variety hederacea, which has three-lobed leaves. Variety integriuscula Gray, has leaves which are entire. This plant is less common than the former.
Stems - Vining, twining, herbaceous, to many meters long, with a combination of long and short pubescence (the hairs mostly retrorse, the longest with pustulose bases), mostly terete.
Leaves - Alternate, petiolate. Petioles to +12cm long, pubescent as the stem, with a shallow adaxial groove. Blades typically 3-lobed but simple also, pubescent above and below, to 15cm broad and long. Lobes typically acuminate and entire.
Inflorescence - Axillary pedunculate clusters(cymes) of typically 3 flowers. Peduncles to 6cm long, pubescent as the stem, often purple at the base. Pedicels short, 3-5mm long, retrorse pubescent (the hairs short). Each division of the inflorescence subtended by opposite linear-attenuate bracts. Bracts to -3cm long, 2-3mm broad, spreading pubescent, reduced upwards.
Flowers - Corolla blue, funnelform, to +3.5cm long, 5cm broad, glabrous internally and externally. Stamens 5, included, adnate near the base of the corolla tube. Filaments white, to 1.5cm long, mostly glabrous but with distinct thickened hairs at the base. Anthers white, 2mm long, 1.5mm broad. Ovary superior, white, glabrous, subtended by white nectariferous ring, 1.5mm in diameter, conic, 3-locular. Placentation axile. Seeds 6. Style white, glabrous, included, 1.6cm long. Stigma biglobose, 2mm in diameter. Sepals 5, long-aristate, expanded at base for 6-7mm, 2.5cm long in flower, longer in fruit, glabrous internally. Basal portion with dense long spreading hairs. Arista short pubescent.
Flowering - June - October.
Habitat - Waste ground, disturbed sites, thickets, roadsides, railroads.
Origin - Native to Central and South America.
Other info. - This is an attractive vine but it can be tough to get rid of once established. This species frequently occurs in flower beds and cultivated areas. The flowers only last one day before wilting. Because this species is found throughout the world there is some confusion about it's origin. Most tend to agree the plant is from the American tropics.
The typical variety found is variety hederacea, which has three-lobed leaves. Variety integriuscula Gray, has leaves which are entire. This plant is less common than the former.
0
0
文章
Dummer. ゛☀
2017年07月28日
Family - Asteraceae
Stems - To 1m tall, herbaceous, branching in apical 1/2, moderately antrorse pubescent (densely in inflorescence), erect, from rhizomes and thickened roots, terete.
Leaves - Alternate, sessile, clasping, auriculate. Internodes below the inflorescence 2-3cm long. Blades entire, acute, oblong, to +6cm long, 1.5-2cm broad, scabrous, sparse pubescent above, more so below. Leaves greatly reduced in inflorescence to bracts. Lower cauline leaves typically dried by anthesis.
Inflorescence - Terminal flower heads in a loose paniculate arrangement. Peduncles long, with greatly reduced leaves, striate.
Involucre - Cylindric, to 5-6mm long, 4-5mm in diameter. Phyllaries imbricate, glandular pubescent and puberulent, just the apices spreading and often reddish-purple, glabrous internally in the basal 2/3, with scarious margins and a green midrib, acuminate, 4-5mm long, 1-1.2mm broad, linear-oblong.
Ray flowers - Flowers 15-20 per head, fertile, pistillate. Ligules blue, to +1cm long, 2-2.5mm broad, minutely 3-lobed at apex (use a lens to see), glabrous. Corolla tube pubescent, whitish, 4-5mm long. Style exserted from beyond the corolla tube, white, glabrous. Stigmas yellow, 1.1mm long. Achenes quadrangular, white, densely retrorse ciliate, 1mm long in flower. Pappus of barbellate capillary bristles to 5mm long. Bristles tan to cinnamon.
Disk flowers - Disk 5-9mm broad. Corolla pale yellow, to 6mm long, glabrous, 5-lobed. Lobes acute, mostly erect, .8mm long, yellow. Stamens 5, slightly exserted, adnate at the base of the corolla tube. Filaments thin, glabrous, translucent. Anthers yellow to tan, to 2mm long, connate around the style. Style bifurcate, exserted slightly beyond the anthers, glabrous, translucent. Stigmas yellow, slightly compressed, 1.5mm long, pubescent in apical 1/2. Achenes and pappus as in ray flowers. Receptacle flat, naked.
Flowering - August - October.
Habitat - Rocky and sandy open woods, thickets, glades.
Origin - Native to U.S.
Other info. - This attractive species can be found in the southern 1/2 of Missouri. The plant is fairly easy to ID (for an Aster) because of its big blue flower heads and hairy stems, which have long internodes. Aster novae-angliae L. is similar but has much shorter internodes and flower heads with many more ray flowers. A. oblongifolius Nutt. is very similar also but has many more cauline leaves below the branching of the inflorescence and more spreading hairs on its stems.
Stems - To 1m tall, herbaceous, branching in apical 1/2, moderately antrorse pubescent (densely in inflorescence), erect, from rhizomes and thickened roots, terete.
Leaves - Alternate, sessile, clasping, auriculate. Internodes below the inflorescence 2-3cm long. Blades entire, acute, oblong, to +6cm long, 1.5-2cm broad, scabrous, sparse pubescent above, more so below. Leaves greatly reduced in inflorescence to bracts. Lower cauline leaves typically dried by anthesis.
Inflorescence - Terminal flower heads in a loose paniculate arrangement. Peduncles long, with greatly reduced leaves, striate.
Involucre - Cylindric, to 5-6mm long, 4-5mm in diameter. Phyllaries imbricate, glandular pubescent and puberulent, just the apices spreading and often reddish-purple, glabrous internally in the basal 2/3, with scarious margins and a green midrib, acuminate, 4-5mm long, 1-1.2mm broad, linear-oblong.
Ray flowers - Flowers 15-20 per head, fertile, pistillate. Ligules blue, to +1cm long, 2-2.5mm broad, minutely 3-lobed at apex (use a lens to see), glabrous. Corolla tube pubescent, whitish, 4-5mm long. Style exserted from beyond the corolla tube, white, glabrous. Stigmas yellow, 1.1mm long. Achenes quadrangular, white, densely retrorse ciliate, 1mm long in flower. Pappus of barbellate capillary bristles to 5mm long. Bristles tan to cinnamon.
Disk flowers - Disk 5-9mm broad. Corolla pale yellow, to 6mm long, glabrous, 5-lobed. Lobes acute, mostly erect, .8mm long, yellow. Stamens 5, slightly exserted, adnate at the base of the corolla tube. Filaments thin, glabrous, translucent. Anthers yellow to tan, to 2mm long, connate around the style. Style bifurcate, exserted slightly beyond the anthers, glabrous, translucent. Stigmas yellow, slightly compressed, 1.5mm long, pubescent in apical 1/2. Achenes and pappus as in ray flowers. Receptacle flat, naked.
Flowering - August - October.
Habitat - Rocky and sandy open woods, thickets, glades.
Origin - Native to U.S.
Other info. - This attractive species can be found in the southern 1/2 of Missouri. The plant is fairly easy to ID (for an Aster) because of its big blue flower heads and hairy stems, which have long internodes. Aster novae-angliae L. is similar but has much shorter internodes and flower heads with many more ray flowers. A. oblongifolius Nutt. is very similar also but has many more cauline leaves below the branching of the inflorescence and more spreading hairs on its stems.
0
0
文章
Dummer. ゛☀
2017年07月28日
Family - Asteraceae
Stems - Single or (rarely) multiple from the base, erect, herbaceous, simple, retrorse pubescent, pale green to yellowish, thin, 1-3mm in diameter, terete.
Leaves - Alternate, dense on the stem, linear to somewhat spatulate (slightly broader at the apex), with a minute bristle tip, scabrous, with strigillose margins, shiny deep green above, lighter below, 2-3cm long, 2-3mm broad, slightly shorter and thicker in strong sun, abruptly reduced just below the flower heads.
Inflorescence - Single (typically) flowerhead terminating the stem.
Involucre - To 1cm long, 4-5mm in diameter, cylindrical. Phyllaries glabrous, imbricate, appressed, to 7mm long, +/-1mm broad, linear, scarious, with a white midrib and light green apices, acute. Apices ciliolate.
Ray flowers - +/-14 per flowerhead, fertile, pistillate. Corolla tube green, 3mm long, antrorse pubescent near the apex. Style glabrous, green-translucent, 3mm long, bifurcate in the apical 1mm. Stigmas erect. Pappus white, of capillary bristles. Bristles to 5mm long, antrorse barbellate. Achenes whitish, 3mm long in flower, densely antrorse pubescent.
Disk flowers - Disk 4-5mm in diameter. Corollas glabrous, 6mm long, white basally, yellow apically , 5-lobed. Lobes acute, 1mm long, erect to slightly spreading. Stamens 5, adnate at the base of the corolla tube. Filaments glabrous, 4mm long, pale yellow-translucent. Anthers yellow, 2mm long, included to partially exserted, connate around the style. Style bifurcate, glabrous, yellowish at the apex, whitish basally, +/-4mm long. Stigmas 1.5mm long erect. Pappus as in ray flowers. Achenes as in ray flowers but slightly smaller.
Flowering - August - October.
Habitat - Dry, rocky pine, pine-oak, or oak-hickory woods. Also on glades and upland slopes.
Origin - Native to U.S.
Other info. - This little species can be found in the southern 1/3 of Missouri. The plant is probably the easiest in the genus to identify because of its thin leaves (which appear somewhat whorled), its single terminal flowerhead on each stem, its small size, and its habitat.
Plants growing in clear-cut areas can get multiple stems from the base and grow more robust than plants in wooded areas. The typical habit of the plant is shown above.
Stems - Single or (rarely) multiple from the base, erect, herbaceous, simple, retrorse pubescent, pale green to yellowish, thin, 1-3mm in diameter, terete.
Leaves - Alternate, dense on the stem, linear to somewhat spatulate (slightly broader at the apex), with a minute bristle tip, scabrous, with strigillose margins, shiny deep green above, lighter below, 2-3cm long, 2-3mm broad, slightly shorter and thicker in strong sun, abruptly reduced just below the flower heads.
Inflorescence - Single (typically) flowerhead terminating the stem.
Involucre - To 1cm long, 4-5mm in diameter, cylindrical. Phyllaries glabrous, imbricate, appressed, to 7mm long, +/-1mm broad, linear, scarious, with a white midrib and light green apices, acute. Apices ciliolate.
Ray flowers - +/-14 per flowerhead, fertile, pistillate. Corolla tube green, 3mm long, antrorse pubescent near the apex. Style glabrous, green-translucent, 3mm long, bifurcate in the apical 1mm. Stigmas erect. Pappus white, of capillary bristles. Bristles to 5mm long, antrorse barbellate. Achenes whitish, 3mm long in flower, densely antrorse pubescent.
Disk flowers - Disk 4-5mm in diameter. Corollas glabrous, 6mm long, white basally, yellow apically , 5-lobed. Lobes acute, 1mm long, erect to slightly spreading. Stamens 5, adnate at the base of the corolla tube. Filaments glabrous, 4mm long, pale yellow-translucent. Anthers yellow, 2mm long, included to partially exserted, connate around the style. Style bifurcate, glabrous, yellowish at the apex, whitish basally, +/-4mm long. Stigmas 1.5mm long erect. Pappus as in ray flowers. Achenes as in ray flowers but slightly smaller.
Flowering - August - October.
Habitat - Dry, rocky pine, pine-oak, or oak-hickory woods. Also on glades and upland slopes.
Origin - Native to U.S.
Other info. - This little species can be found in the southern 1/3 of Missouri. The plant is probably the easiest in the genus to identify because of its thin leaves (which appear somewhat whorled), its single terminal flowerhead on each stem, its small size, and its habitat.
Plants growing in clear-cut areas can get multiple stems from the base and grow more robust than plants in wooded areas. The typical habit of the plant is shown above.
0
0
文章
Dummer. ゛☀
2017年07月28日
Family - Asteraceae
Stems - To 1m tall, glabrous to hispidulous, single from the base, typically simple in the lower 1/2, terete, erect, herbaceous.
Leaves - Alternate. Basal leaves long petiolate, the petiole to +15cm long. Blades of basal leaves cordate to truncate or abruptly narrowed at base, very scabrous above and below, to 10cm long, 7cm wide. Middle and upper cauline leaves greatly reduced as compared to basal leaves, 2-10mm broad, sessile, appearing as linear bracts near inflorescence.
Inflorescence - Loosely paniculate, open, many flowered(+75) but the flowers opening at different times.
Involucre - 4.5-7mm tall (long), cylindric. Phyllaries imbricate, lanceolate, appressed, mostly whitish with distinct rhombic green tips, margins minutely ciliolate.
Ray flowers - Ligules blue, to 9mm long, typically +/- 15 per flower head.
Disk flowers - Disk 4-5mm broad. Corollas yellow, small, 15-30 per head. Achenes glabrous, +/-1mm long. Pappus of capillary bristles, +2.5mm long.
Flowering - September - October.
Habitat - Open woods, prairies, pastures, glades, roadsides.
Origin - Native to U.S.
Other info. - This little but showy species can be found scattered throughout much of Missouri. Steyermark wrote, however, that it is found in less than half the counties in the state.
The plant is easy to identify because of its leaves, which are very scabrous - almost like sandpaper. The small blue flowers and green diamond-tipped phyllaries help also. Plants with glabrous stems can be growing right next to those with hispidulous stems so stem pubescence is NOT a good character to use for identification.
Stems - To 1m tall, glabrous to hispidulous, single from the base, typically simple in the lower 1/2, terete, erect, herbaceous.
Leaves - Alternate. Basal leaves long petiolate, the petiole to +15cm long. Blades of basal leaves cordate to truncate or abruptly narrowed at base, very scabrous above and below, to 10cm long, 7cm wide. Middle and upper cauline leaves greatly reduced as compared to basal leaves, 2-10mm broad, sessile, appearing as linear bracts near inflorescence.
Inflorescence - Loosely paniculate, open, many flowered(+75) but the flowers opening at different times.
Involucre - 4.5-7mm tall (long), cylindric. Phyllaries imbricate, lanceolate, appressed, mostly whitish with distinct rhombic green tips, margins minutely ciliolate.
Ray flowers - Ligules blue, to 9mm long, typically +/- 15 per flower head.
Disk flowers - Disk 4-5mm broad. Corollas yellow, small, 15-30 per head. Achenes glabrous, +/-1mm long. Pappus of capillary bristles, +2.5mm long.
Flowering - September - October.
Habitat - Open woods, prairies, pastures, glades, roadsides.
Origin - Native to U.S.
Other info. - This little but showy species can be found scattered throughout much of Missouri. Steyermark wrote, however, that it is found in less than half the counties in the state.
The plant is easy to identify because of its leaves, which are very scabrous - almost like sandpaper. The small blue flowers and green diamond-tipped phyllaries help also. Plants with glabrous stems can be growing right next to those with hispidulous stems so stem pubescence is NOT a good character to use for identification.
0
0
文章
Miss Chen
2017年07月27日
1.Para prevenir problemas sanitarios mantener las plantas fuertes y bien cuidadas en cuanto a riego, fertilización, clima adecuado, etc., resistirán mucho mejor los ataques de insectos y hongos.
2.Si vuelves a poner la misma especie en un sitio con problemas de plagas o enfermedades, es probable que de nuevo se infecte, porque los parásitos se conservan; planta otra especie.
3.Pulveriza las plantas que en años anteriores tuvieron problemas con hongos; ya que es probable que reaparezcan.
4.Es mucho más fácil combatir una plaga de insectos u hongo en la fase inicial que esperar a que se extienda.
5.El exceso de humedad facilita la aparición de hongos.
6.Trata con fungicida las manchas amarillas o pardas que aparezcan en el césped si se sospecha de hongos. Así no se extenderán.
7.Aplica un fungicida de amplio aspectro para prevenir hongos como Botritis, Oidio, Roya y Mildiu.
8.La Negrilla o Fumagina aparece donde hay Pulgones, Cochinillas o Mosca blanca, ya que se asientan sobre la melaza que éstos excretan. Elimina las plagas y no habrá Negrilla.
9.Botritis (Botrytis cinerea) es un moho de color gris que ataca todas las partes de la planta: tallos, hojas, flores y frutos. Se previene con fungicidas y evitando las heridas, que es por donde penetra.
10.Fitóftora (Phytophtora spp.) es un hongo que empieza atacando el sistema radicular y sigue por el cuello de la planta. Se propaga con rapidez y acaba con la planta. Aparece cuando el suelo está muy húmedo. Destruye setos de Coníferas, árboles, arbustos, naranjos...
11.No aproveches los esquejes de plantas enfermas porque también estarán infectados.
12.Los Pulgones es posible combatirlos pulverizando con agua jabonosa. Llena de agua un pulverizador de litro o litro y medio y añade una cucharadita de lavavajillas, jabón natural o jabón de potasa. Rocía las plantas.
13.Captura a mano escarabajos, orugas, gusanos...
14.Captura babosas y caracoles con trampas de cerveza, a mano al atardecer o con cebos especiales.
15.Hojas arrugadas en naranjo, mandarino o limonero se debe a alguna de estas plagas: Minador de los cítricos, Pulgones o Mosca blanca. Clorosis férrica
16.El amarilleo de hojas puede obedecer a la falta de hierro en el suelo o a riego permanente con aguas calcáreas (duras).
17.El agua del grifo es a menudo muy calcárea, lo que amarillea las hojas en ciertas especies sensibles a este problema, llamadas acidófilas: Azalea, Rododendro, Glicina, Camelia, Fucsia, Hortensia o Brezo.
18.Trata estas acidófilas con Sulfato de hierro (25 grs. o 1 cucharada por planta grande o 1 cucharadita por cada macetero mediano) o bien con quelatos de hierro (1/2 cucharadita por planta). Luego riega.
0
0
文章
Miss Chen
2017年07月27日
1.Acaricida (Glosario de Fitopatología)
Producto fitosanitario usado en el control de ácaros o arañitas.
Los ácaros se reproducen varias veces al año y causan daños serios en las plantas. Destaca entre ellos la Araña roja (Tetranychus urticae).
2.Aceite amarillo (aceite de invierno) (Glosario de Fitopatología)
Aceite de uso preventivo contra plagas que, debido a su elevada toxicidad para las hojas, sólo puede ser empleado en la etapa de paro vegetativo de la planta, cuando no tiene hojas. Ejemplo: árboles frutales de hoja caduca se aplica en invierno.
3.Aceite blanco (aceite de verano) (Glosario de Fitopatología)
Producto similar al anterior pero de menor fitoxicicidad por lo que puede emplearse cuando las plantas tienen follaje.
4.Azufre (Glosario de Fitopatología)
Elemento químico usado para combatir hongos. Buena eficacia contra Oidio. También mata bastantes ácaros.
Azufrar se denomina a espolvorear las viñas con azufre, para preservarlas del Oidio (Ceniza) y otras plagas.
5.Bacillus thuringiensis (Glosario de Fitopatología)
Bacteria natural presente en el suelo, usada durante más de 30 años con buenos resultados por jardineros y agricultores orgánicos como bioinsecticida para controlar determinadas plagas.
Cuando el insecto al atacar el cultivo lo ingiere. El Bacillus thuringiensis produce una proteína (toxina Bt) que es tóxica solamente a ciertas larvas de insecto que lo consumen.
6.Fitopatología (Glosario de Fitopatología)
Ciencia que estudia las enfermedades y plagas de las plantas.
7.Fungicida (Glosario de Fitopatología)
Producto químico utilizado para combatir las enfermedades causadas por hongos.
8.Glifosato (Glosario de Fitopatología)
Compuesto químico que se aplica como herbicida de acción total sistémico. Total significa que afecta a todo tipo de plantas, es decir, no es selectivo, y sistémico significa que penetra dentro de la planta y a través de la savia puede llegar hasta las raíces para secar éstas.
9.Herbicida (Glosario de Fitopatología)
Compuesto químico para disminuir o inhibir el crecimiento o matar las malas hierbas.
Existen herbicidas selectivos (solo atacan a determinados tipos de hierbas, por lo tanto se utilizan en cultivos) y herbicidas totales (matan todo tipo de hierbas).
Los herbicidas deben ser utilizados con mucha precaución puesto que suelen ser productos muy tóxicos.
10.Helicida (Glosario de Fitopatología)
Controlan el crecimiento de caracoles y babosas. A veces, estos gasterópodos proliferan en exceso, por lo que no se queda más remedio que limitar su número. Existen métodos de control que no son químicos.
11.Hongo (Glosario de Fitopatología)
Organismo vegetal que no tiene clorofila, como los mohos y las setas, y obtiene su alimento de otros organismos vivos (parásito) o de materia muerta (saprófito).
Es la causa más común de infecciones en rosas con mildiu, mancha negra, oidio y roya.
12.Insecticida (Glosario de Fitopatología)
Un insecticida es un producto químico utilizado para combatir las plagas de insectos.
Se puede aplicar en forma de polvo, líquido, pulverizado o aerosol.
Los pesticidas convencionales tienen el inconveniente de no ser suficientemente selectivos, es decir, que eliminan junto con el parásito otros insectos útiles, entre ellos los enemigos del parásito, con lo cual al cabo de poco tiempo se produce el conocido efecto rebote, es decir, que el parásito, que generalmente tiene un potencial reproductivo mucho mayor, al verse libre de sus enemigos se multiplica rápidamente reapareciendo el problema con mayor intensidad.
De esta manera, se obliga a repetir una y otra vez los tratamientos, con lo que se agravan los riesgos de presencia de residuos de pesticidas o sus metabolitos en los alimentos y la contaminación del entorno.
Además, no toda la población tratada con un determinado pesticida muere, algunos individuos, por mecanismos de selección, son capaces de sobrevivir, transfiriendo a su descendencia esta capacidad de resistencia frente al insecticida, con lo que al cabo de poco tiempo, una gran parte de la población se ha hecho resistente y es necesario sustituir el insecticida por otro diferente.
13.Larva (Glosario de Fitopatología)
Fase del ciclo del insecto que pasa por una metamorfosis completa: huevo, larva, crisálida o pupa y adulto.
En el caso de las mariposas (lepidópteros) a la larva se le suele llamar "oruga", y en el caso de los escarabajos (coleópteros), a la larva se le denomina "gusano".
14.Manejo Integrado de Plagas (MIP) (Glosario de Fitopatología)
Una combinación de métodos con y sin plaguicidas para controlar plagas.
Estrategia que involucra la selección, integración e implementación de métodos de manejo o control de organismos dañinos para los vegetales con un enfoque de sistemas, considerando el impacto socioeconómico y ecológico.
La finalidad es mantener el tamaño de la población de una plaga por debajo del tamaño que causa pérdidas económicamente inaceptables de un cultivo, de un ganado o de animales de granja.
Sinónimo: Control Integrado de Plagas.
15.Nematicida (Glosario de Fitopatología)
Producto destinado a combatir los nematodos que atacan a las plantas.
Los nematodos son pequeños gusanos (microscópicos) que viven en la tierra y que se alimentan de las raíces.
No ha habido demasiado éxito en la lucha por controlarlos con productos químicos. A veces es conveniente además limpiar el suelo con desinfectantes.
0
0
文章
Dummer. ゛☀
2017年07月27日
Family - Lamiaceae
Stems - To +20cm tall, multiple from base, simple, from fibrous roots, 4-angled, 1-3mm thick, densely glandular and simple pubescent to glabrous or sparse pubescent, herbaceous, erect.
Leaves - Opposite, sessile, entire, ovate, to +/-1.5cm long, +/-8mm broad, densely glandular pubescent or sparsely pubescent. Margins sometimes revolute.
Inflorescence - Paired axillary flowers. Pedicels 2-3mm long, hirsute.
Flowers - Corolla tubular, bilabiate, to 1cm long, externally pubescent. Lower lip +3mm broad, mottled with violet and white, larger than upper lip. Upper lip galeate. Stamens 4, didynamous, included within upper lip. Filaments to 3.5mm long, white, glabrous. Ovary 4-lobed. Calyx 2-lobed, with dorsal protuberance on upper lobe, densely glandular pubescent, 3.5mm long, accrescent.
Flowering - April - July.
Habitat - Glades, open woods, prairies, bluffs.
Origin - Native to U.S.
Other info. - This is a tiny plant which can be easily overlooked. The plant produces a "moniliform" rhizome, which means "constricted at regular intervals" (like a pearl necklace, for example). It sort of resembles roots infected with nematodes.
The plant can be found in rocky open areas of the habitats mentioned above.
Steyermark lists three varieties for the plant based on leaf, stem, and calyx pubescence and leaf morphology. I won't go into those here.
In the same habitat as this plant you can usually find many a Centruroides scorpion:
Fortunately, I like scorpions. I used to breed a few different species and donated part of my collection to a fellow named Kari McWest, so he could finish his graduate research. Kari - drop me a line.
Stems - To +20cm tall, multiple from base, simple, from fibrous roots, 4-angled, 1-3mm thick, densely glandular and simple pubescent to glabrous or sparse pubescent, herbaceous, erect.
Leaves - Opposite, sessile, entire, ovate, to +/-1.5cm long, +/-8mm broad, densely glandular pubescent or sparsely pubescent. Margins sometimes revolute.
Inflorescence - Paired axillary flowers. Pedicels 2-3mm long, hirsute.
Flowers - Corolla tubular, bilabiate, to 1cm long, externally pubescent. Lower lip +3mm broad, mottled with violet and white, larger than upper lip. Upper lip galeate. Stamens 4, didynamous, included within upper lip. Filaments to 3.5mm long, white, glabrous. Ovary 4-lobed. Calyx 2-lobed, with dorsal protuberance on upper lobe, densely glandular pubescent, 3.5mm long, accrescent.
Flowering - April - July.
Habitat - Glades, open woods, prairies, bluffs.
Origin - Native to U.S.
Other info. - This is a tiny plant which can be easily overlooked. The plant produces a "moniliform" rhizome, which means "constricted at regular intervals" (like a pearl necklace, for example). It sort of resembles roots infected with nematodes.
The plant can be found in rocky open areas of the habitats mentioned above.
Steyermark lists three varieties for the plant based on leaf, stem, and calyx pubescence and leaf morphology. I won't go into those here.
In the same habitat as this plant you can usually find many a Centruroides scorpion:
Fortunately, I like scorpions. I used to breed a few different species and donated part of my collection to a fellow named Kari McWest, so he could finish his graduate research. Kari - drop me a line.
0
0
文章
Dummer. ゛☀
2017年07月27日
Family - Lamiaceae
Stems - To 50cm tall, herbaceous, erect, from a taproot, single from the base, branching above middle, pubescent with retrorse viscid hairs.
Leaves - Opposite, descussate, entire, narrowly ovate to elliptic, 3-nerved, to +2.5cm long, +1cm broad, pubescent to (less commonly) glabrous, sessile or very short-petiolate, cuneate at the base, acute at the apex.
Inflorescence - One or two pedunculate flowers in leaf axils. Peduncles short, 2-4mm long.
Flowers - Corolla purple, to 5mm long, tubular, bilabiate. Upper lobes 4, spreading, shorter than corolla tube. Lower lobe slightly longer than upper lobes. Stamens 4, exserted beyond the corolla. Stigma 2-lobed. Ovary 4-parted. Calyx with a pair of stipule-like bracts at base. Calyx lobes acute to attenuate, one nerved, 4mm long, entire, pubescent, viscid.
Flowering - July - October.
Habitat - Along streams on gravel bars, glades, rocky banks, outcroppings.
Origin - Native to U.S.
Other info. - This plant is common along the many streams and creeks of the state. It is easy to identify because of its three-nerved leaves and small purple flowers.
Another variety, variety linearis Fassett., has linear leaves. This latter variety is not found in Missouri.
A synonym is Trichostema brachiatum L.
Stems - To 50cm tall, herbaceous, erect, from a taproot, single from the base, branching above middle, pubescent with retrorse viscid hairs.
Leaves - Opposite, descussate, entire, narrowly ovate to elliptic, 3-nerved, to +2.5cm long, +1cm broad, pubescent to (less commonly) glabrous, sessile or very short-petiolate, cuneate at the base, acute at the apex.
Inflorescence - One or two pedunculate flowers in leaf axils. Peduncles short, 2-4mm long.
Flowers - Corolla purple, to 5mm long, tubular, bilabiate. Upper lobes 4, spreading, shorter than corolla tube. Lower lobe slightly longer than upper lobes. Stamens 4, exserted beyond the corolla. Stigma 2-lobed. Ovary 4-parted. Calyx with a pair of stipule-like bracts at base. Calyx lobes acute to attenuate, one nerved, 4mm long, entire, pubescent, viscid.
Flowering - July - October.
Habitat - Along streams on gravel bars, glades, rocky banks, outcroppings.
Origin - Native to U.S.
Other info. - This plant is common along the many streams and creeks of the state. It is easy to identify because of its three-nerved leaves and small purple flowers.
Another variety, variety linearis Fassett., has linear leaves. This latter variety is not found in Missouri.
A synonym is Trichostema brachiatum L.
0
0
文章
Dummer. ゛☀
2017年07月26日
Family - Scrophulariaceae
Stems - To 20cm tall (typically shorter), erect, herbaceous, branching, terete, densely glandular pubescent, from a taproot.
Leaves - Opposite, decussate, pinnatifid to bipinnatifid in the apical 1/2, glandular pubescent, to 1.8cm long, 1.3cm broad. Ultimate leaf divisions linear to oblong or oblanceolate, entire.
Inflorescence - Typically single flowers from upper leaf axils. Pedicels to 3mm in flower, slightly longer in fruit, densely glandular pubescent.
Flowers - Corolla bilabiate, pale blue to lilac, to +4mm long, glabrous externally, sparse pilose internally. Upper lip single-lobed. The lobe with a notched at the apex, to -2mm broad, -1mm long. Lower lip 3-lobed. The lobes mostly equal, to 1.2mm long. Corolla tube to 2.5-3mm long, expanded and white at the base. Stamens 4, didynamous, adnate near middle of corolla tube, included. Filaments to 1.3mm long, white, glabrous. Anthers pale yellow to white .1-.2mm broad. Ovary superior, green, glabrous, +/-1mm long in flower, ovoid, 2-locular. Ovules many. Placentation axile. Style 1.1mm long, glabrous, green. Stigma 2-lobed. Sepals 5, barely united at the base for -1mm, to +2mm long in flower, +4mm in fruit, .3mm broad, linear-attenuate, slightly spreading at the tips or erect, glandular pubescent. Calyx accrescent. Capsule green, glabrous, 2-valved.
Flowering - May - October.
Habitat - Gravel bars of streams, moist ground of fields and prairies, mud flats, low woods, roadsides.
Origin - Native to U.S.
Other info. - This is one of those plants that most people would see as a weed in need of a good shower of "Round-Up". Closer inspection, however, reveals a neat little plant with very nice yet small flowers. The plant can be found throughout most of Missouri except may of the northern counties.
A synonym is Leucospora multifida (Michx.) Nutt.
Stems - To 20cm tall (typically shorter), erect, herbaceous, branching, terete, densely glandular pubescent, from a taproot.
Leaves - Opposite, decussate, pinnatifid to bipinnatifid in the apical 1/2, glandular pubescent, to 1.8cm long, 1.3cm broad. Ultimate leaf divisions linear to oblong or oblanceolate, entire.
Inflorescence - Typically single flowers from upper leaf axils. Pedicels to 3mm in flower, slightly longer in fruit, densely glandular pubescent.
Flowers - Corolla bilabiate, pale blue to lilac, to +4mm long, glabrous externally, sparse pilose internally. Upper lip single-lobed. The lobe with a notched at the apex, to -2mm broad, -1mm long. Lower lip 3-lobed. The lobes mostly equal, to 1.2mm long. Corolla tube to 2.5-3mm long, expanded and white at the base. Stamens 4, didynamous, adnate near middle of corolla tube, included. Filaments to 1.3mm long, white, glabrous. Anthers pale yellow to white .1-.2mm broad. Ovary superior, green, glabrous, +/-1mm long in flower, ovoid, 2-locular. Ovules many. Placentation axile. Style 1.1mm long, glabrous, green. Stigma 2-lobed. Sepals 5, barely united at the base for -1mm, to +2mm long in flower, +4mm in fruit, .3mm broad, linear-attenuate, slightly spreading at the tips or erect, glandular pubescent. Calyx accrescent. Capsule green, glabrous, 2-valved.
Flowering - May - October.
Habitat - Gravel bars of streams, moist ground of fields and prairies, mud flats, low woods, roadsides.
Origin - Native to U.S.
Other info. - This is one of those plants that most people would see as a weed in need of a good shower of "Round-Up". Closer inspection, however, reveals a neat little plant with very nice yet small flowers. The plant can be found throughout most of Missouri except may of the northern counties.
A synonym is Leucospora multifida (Michx.) Nutt.
0
0
