Phaseolus vulgaris (Fabaceae)
| 1998 | 1999 | 2000 | 2001 | 2002 | |
| Acres in Wyoming: | 37,000 | 39,000 | 34,000 | 24,000 | 29,000 |
| Percent U.S. Acreage: | 1.9% | 1.5% | 2.1% | 1.9% | 1.7% |
| National Ranking: | 9th | 8th | 8th | 9th | 9th |
| Per Acre Value (Net): | $360.32 | $323.28 | $376.53 | $492.58 | $400.21 |
| Value of Production in Wyoming: | $13,332,000 | $12,608,000 | $12,802,000 | $11,822,000 | $11,606,000 |
Data from 1999-2003 Wyoming Agricultural Statistics Services
Description of Crop
Dry beans are annual legumes grown for their seed. All of the following beans are considered dry beans: navy beans, light red kidney beans, great northern beans, pinto beans, black turtle soup beans, anasazi beans, and others. The principle dry bean market class grown in Wyoming is pinto beans (85 - 90%). Goshen County is ranked #1 in the state in production with 9,800 acres of dry edible beans. The northwest and southeast regions harvests all of the acres of dry beans in eight different counties, mostly pinto dry beans.Cropping system
Beans are planted between May 20 and July 1 in firm, non-compacted soil. The following seed bed requirements optimize germination and growth: temperature of at least 60 F, a pH of 8 or less, and a salinity level that does not exceed 3 millimol/L. Inoculating the soil with Rhizobium bacteria during planting will encourage a symbiotic relationship between nitrogen fixing bacteria and the root nodules of dry beans. These bacteria add useable nitrogen to the soil for plant uptake. Moderate fertilizer application may also be required, especially if there is no nodulation. Fertilizer recommendations range from 50 - 75 lb of nitrogen, 0 - 75 lb of phosphorous and 0 - 5 lb of zinc. Row spacing should not exceed 30", and seed should be planted about 2" into the soil (but no more than 4").
Crop rotation is imperative to the success of the crop. For irrigated beans, a 3 - 4 year rotation with corn, barley, wheat and alfalfa is recommended, whereas dryland beans should be part of a 3-year rotation with grain sorghum, wheat, sunflowers, and a year of fallow preceding the beans. An alfalfa crop should not directly precede dry beans because of the volunteer perennial weed aspect of alfalfa. Dry beans should not be planted after potatoes or sugarbeets if either crop was affected by Rhizoctonia root or crown rot. Avoid planting after potatoes for three years. Beans should also not be planted after irrigated sunflowers due to white mold susceptibility.
Tillage is necessary for the success of dry beans. Deep ripping of the soil reduces soil compaction and root rot stress. Ridging soil around the base of plants is necessary to promote secondary root development and to facilitate bean cutting and pulling. Beans are ready for cutting and pulling when 33 to 50% of the pods turn yellow. All harvesting should be done before the fall frost.
Location of Production
Southeast District Counties:
Goshen, Laramie, Platte
Key Insects
Bean leaf beetles are about 0.25" long, with considerable variation in color patterns. The background color may be yellow, green, tan, or red. Most beetles have four black spots and black stripes along the edges of the wing covers. A black triangle is always present at the base of the wing covers just behind the prothorax. The larvae are white, with dark brown areas at both ends. When mature, the larvae are about 0.375 - 0.5 inches long. Bean leaf beetles overwinter as adults under debris in protected areas. When temperatures rise in the spring, beetles fly into alfalfa and clover fields to feed but do not lay eggs there. As soon as beans begin emerging, the beetles abandon alfalfa and clover fields to colonize bean fields. Females lay eggs in the soil around the base of the plant. The lemon shaped eggs are laid in clusters of 12 - 24 and are orange. The eggs hatch in 1 - 3 weeks depending on the weather. Larvae feed on the roots and nodules of the plants then form an earthen pupation cell. The pupal stage lasts approximately one to two weeks. When adults emerge, they feed on soybean foliage. In most parts of Wyoming, bean leaf beetles complete one generation per year. There has been some indication that a complete or partial second generation may occur in southern parts of the state. The injury caused by the bean leaf beetle is two-fold. The adults feed on the leaves of the plants causing the characteristic "shot-hole" appearance on the leaves. They also feed on the roots and underground portion of the stem, girdling and killing the plant. Late in the season, bean leaf beetles may chew on pods. Their feeding creates scars that allow infection by some fungal diseases. Mild infection results in seed staining; severe infection results in seed contamination.
Beet Leafhoppers, Circulifer tenellus
Beet leafhoppers feed on the undersides of dry bean leaves. Severe infestation, a rare occurrence, can cause leaf cupping and discoloration. Adult beet leafhoppers are pale green, active and about 0.125" long. There are three or more generations per year, and the insect can be found throughout the bean growing season. Hot, dry conditions favor development of this insect, which is a vector of curly top virus. Control of beet leafhopper in dry beans is generally not recommended.
Mexican Bean Beetle, Epilachna varivestris
The Mexican bean beetle can be a serious pest of beans in Wyoming. The adult Mexican bean beetle is 0.25 - 0.33" in length and has an oval, pale-yellow, convex body when newly emerged. As the adult matures, it changes to a copper brown color. It has 16 black spots on its back. Larvae are yellow-orange, about 0.33" in length, and are covered with dark, branched spines that give them a fuzzy appearance. The adults overwinter at the soil surface under plant debris and sometimes in large groups in hedgerows adjacent to bean fields. When temperatures rise in the spring, beetles fly into alfalfa and clover fields to feed but do not lay eggs there. As soon as beans germinate and begin to grow, the beetles abandon alfalfa and clover fields to colonize bean fields. Seven to 10 days after feeding, females will begin to lay yellowish orange eggs in clusters of 40 to 60 on the undersides of the bean leaves. Each female may lay up to 500 eggs in a 5-week period. In the early part of the season, the eggs take approximately 12 days to hatch, while later in the summer they take only five days. The larvae take about 25 days to mature. Mature larvae attach themselves to the underside of the leaves and weeds to pupate, and are inactive for about a week. The pupae are round, smooth, yellow, and quite often have the last larval skin still attached. Generally, two generations per year develop in Wyoming. Eggs of the first generation will hatch in late June or July, and larvae develop through July into August. The next generation of adults will emerge in late July or early August and lay eggs in August. Larvae of the second generation pupate in late August or early September. Larvae and adults feed on the undersides of leaves, leaving the upper surface intact. The upper leaf surface dries up and falls out so that damaged leaves have open, ragged holes. The larvae feed along parallel lines, leaving strips of uneaten leaves in between. When abundant, these pests also feed on bean pods and stems. Injury reduces plant vigor and in extreme cases, foliage is reduced to shreds, causing plant death.
Onion Thrips and Western Flower Thrips, Thrips tabaci and Frankliniella occidentalis
Two kinds of thrips, onion thrips and western flower thrips, attack dry beans in the region. Thrips are small, active, cigarette-shaped, yellow to brown insects. They rasp the tissue and drain the exuding sap, causing stunted and deformed plants. Thrips are usually pests of seedling plants but may attack plants in any stage. Onion thrips are most commonly associated with furrow irrigated beans grown in close proximity to winter wheat. Onion thrips feeding results in leaf cupping and distortion that is made more severe by plant stress. The crop often outgrows damage with little yield loss. Infestation and damage are often more severe at the edge of the field. Western flower thrips feed on developing flowers and can cause flower and pod abortion. Five western flower thrips per blossom can reduce the number of pods per plant. Western flower thrips unlike onion thrips have proven to be more difficult to reach with contact insecticides. Both of these thrips can transmit tobacco streak virus.
Potato Leafhoppers, Empoasca fabae
The potato leafhopper can be a serious problem in dry beans if leafhoppers arrive early in the season. Leafhoppers overwinter in the Gulf Coast area and migrate into this region in too low of numbers and too late in the season to cause serious damage. Potato leafhoppers are wedge shaped and green, with six white spots on their prothorax. Potato leafhoppers inject a toxin during leaf feeding that damages the plant and results in leaf discoloration and stunting.
Seedcorn Maggots, Delia platura
The adult seedcorn maggot is a hairy, gray fly about 0.2" long that lays eggs in areas high in decaying organic matter. The maggot is yellowish white, legless and about 0.25" long. The first adult activity in the spring occurs in early May during corn planting. Offspring of these adults mature to form a second generation of adults in late May or early June when beans are planted. These adults are attracted to areas of high organic matter that have just been tilled. Maggots will feed on the germinating seed and hollow out or otherwise damage cotyledons. If maggots damage the growing point of the plant, a "snakehead" plant may result. Later feeding by the maggots may be evident as burrowing within the stem. This feeding may increase the incidence of secondary rotting within the stem.
Western Bean Cutworm, Loxagrotis albicosta
Young larvae are light-colored with three short, wide, dark stripes running lengthwise on the first segment behind the head. Western bean cutworms overwinter as pre-pupae within earthen cells formed in the ground. They pupate in May and emerge as moths in July and August. Rainfall and irrigation promote adult emergence from soil. Peak moth activity in Wyoming usually occurs in the last half of July. Shortly after emergence, they lay clusters of eggs, usually 15 - 50 dome-shaped eggs, on the lower surface of the leaves. Larvae mature and cease feeding, at which time they enter the soil and overwinter. There is only one generation per year. Damage by young western bean cutworm larvae is not very noticeable because they feed primarily on tender leaves and flower parts. As bean pods form, cutworms chew holes in the pod walls and feed on developing seed. Feeding occurs primarily at night and during cloudy days. On sunny days, cutworms hide in soil at the base of plants.
Additional Insects
Aphids, Family: Aphididae
Aphid life cycles vary with species. Aphids are small, soft-bodied insects found singly or in clusters on stems or on the undersides of leaves. Aphids overwinter as eggs and adults. The tiny aphids hatch in the spring, mature rapidly and give birth - without mating - to living young. Mature aphids fly to cultivated crops during the spring and summer where they form new colonies. Only females are produced during the summer and with their rapid rate of reproduction, it is possible for large numbers to develop in a short period of time. They may be a problem throughout the season. As cool weather approaches in the fall, both males and females are produced. They mate and lay fertile eggs that overwinter. Aphids attack the leaves, blossoms, pods, and other parts of their host plants, sucking plant juices through their tiny needle-like beaks. Heavily infested plants become stunted and do not produce normal crops. Migrating aphids also can transmit several viral plant diseases.
Army Cutworm, Euxoa auxiliaris
Army cutworm is one of several species of cutworms that attack dry beans in Wyoming. Adult moths are brown with light brown or black markings on the forewings and have a wingspan of about 2". The larvae vary in color from dull green to brown with faint stripes on the back and a brown head. The army cutworm has one generation per year. Eggs hatch in the fall following sufficient moisture. The army cutworm larvae spend the winter as partially grown caterpillars. They feed on warmer days throughout the winter and feed more frequently in the spring as they mature. Army cutworms always feed above ground during the night and/or on cloudy days. They are found under soil clods and other debris during the day. After development is complete, they build a small pupation chamber several inches below the soil surface. Moths emerge in May and June and migrate to higher elevations in the Rocky Mountains to escape high summertime temperatures. The adult moths, commonly reffered to as Miller moths in Wyoming, are a nuisance in homes, but do not lay eggs or reproduce in homes. In late summer and early fall, the moths return to the plains to lay their eggs in wheat fields and in other cultivated areas. With adequate moisture, eggs hatch and larvae of the next generation start feeding as weather conditions permit. The army cutworm will climb on the bean plant and feed on leaves. Adult cutworms are attracted to newly tilled soil to lay their eggs in the fall, and therefore, they are more likely to be a problem in fields planted to winter small-grain cover crops that are destroyed prior to bean planting.
Flea Beetles: Potato Flea Beetle, Three-spotted Flea Beetle, Pale Striped Flea Beetle and Tuber Flea Beetle, Epitrix cucumeris, Disconycha triangularis, Systena blanda and E. tuberis
Adult beetles are typically small, often shiny, and have large rear legs that allow them to jump like a flea when disturbed. Flea beetles overwinter in the adult stage hidden under leaves, dirt clods, or in other protected sites. They become active during warm days in mid spring but may straggle out over several weeks. Many flea beetles are strong fliers and seek out emerging host plants that they locate by chemical clues the plants produce. Adults feed for several weeks. Soon thereafter, females intersperse feeding with egg laying. They lay eggs in soil cracks around the base of the plants. The minute, wormlike larvae then move to feed on small roots and root hairs. The larval stage is completed in about a month. The insects pupate and emerge from the soil as adults. There may be a second generation during the summer and, with a few species, a third generation. Flea beetles produce a characteristic injury known as "shot-holing" in which the adults chew many small holes or pits in the leaves, making them appear as if a fine buckshot has damaged them. Young plants and seedlings are particularly susceptible. Growth may be seriously retarded and plants even killed. Leaf feeding also damages plant appearance, which can impact the marketability of leafy vegetable crops. Although flea beetles are common, injuries are often insignificant to plant health. On established plants, 10 - 20% or more of the leaf area must be destroyed before there are any negative yield effects.
Grasshoppers
Grasshoppers follow roughly a 22-year cycle in Wyoming, with the last major outbreak occurring in the late 1970s and early 1980s. Grasshoppers vary considerably depending on the species. Grasshopper nymphs have a similar appearance to adults but are smaller in size. Grasshoppers lay eggs in undisturbed areas, usually in late summer and early fall. Small nymphs or "hoppers" hatch the following spring. Winged adults will appear 5 - 6 weeks after eggs hatch. A few Wyoming grasshopper species have eggs that hatch in late summer and overwinter as nymphs. Winged adults of these species usually appear early in the following summer, often causing undue alarm about unusually early grasshopper activity. Some of these species are important on rangeland, but none are considered a threat to field crops. The usual pattern of grasshopper damage in field crops is for early development to occur in weedy areas of roadsides, fence rows, irrigation ditches, and other non-crop areas. As these food sources are exhausted or begin to dry down, the grasshoppers leave in search of other food - often an irrigated crop. Here they will first feed in the field margins and subsequently spread throughout the field. Most field crop damage is caused by the differential, red-legged, two-striped, and migratory grasshoppers.
Pale Western Cutworm, Agrotis orthogonia
Pale western cutworm is one of several species of cutworms that attack dry bean. Adult moths emerge from the soil in late summer and fall. Eggs are deposited in loose soil and usually hatch in late winter. Under some conditions, eggs hatch in the fall and the insect overwinters as a partially grown caterpillar. Egg hatch may be delayed for up to several months if moisture and temperature conditions are unfavorable. Larvae prefer loose, sandy or dusty soil and are found most easily in the driest parts of the field, such as hilltops. After feeding is complete, pale western cutworm larvae move to pupal chambers constructed several inches below the soil surface. Adults begin to emerge in August, but most egg laying occurs in September. Pale western cutworm is a subterranean cutworm. It feeds on stems at the crown and can result in severed stems. Entire fields may be lost in a matter of days. Outbreaks are associated with dry conditions in the previous spring. Adults of the cutworm are attracted to newly tilled soil to lay their eggs in the fall, and therefore, they are more likely to be a problem in fields planted to winter small-grain cover crops that are destroyed prior to bean planting
Two-spotted Spider Mite, Tetranychus urticae
The adult female is pale to dark green with conspicuous dark spots on each side. Food showing through the transparent body wall causes these darkened areas. The eggs are spherical, clear and colorless when first laid, becoming opaque and finally ivory just before hatching. The newly hatched larva is colorless at first, though it becomes greenish after feeding. Nymphal (pre-adult) stages are green to pale yellow. Two-spotted spider mites usually overwinter as adult females on the host plant or in nearby debris. These overwintering females are pale orange to straw-colored and active, though they do not produce eggs during the winter. Two-spotted spider mites usually begin colonies on the undersides of plant leaves. Webbing is visible to the naked eye and all stages of mite development occur in and beneath the webbing. Many female mites may be present on each infested leaf. Small colonies usually begin near a leaf vein and with favorable weather spread rapidly to nearby leaves and plants. Infestations are often associated with drought stress and hot, dry weather conditions. Development from egg to adult requires five to 15 days. Feeding usually takes place on lower leaf surface, though occasionally upper leaf surfaces are infested. Light to moderate infestations on lower surfaces are indicated by stippling on upper leaf surfaces. As feeding continues and the mite population grows, leaves become lighter in color as a result of the mites feeding on the green chlorophyll in leaf tissue. Heavily damaged leaves turn tan or bronze, become desiccated and usually die. Little is known about the effect of spider mite feeding on dry bean yield and quality, but the earlier in crop development that infestation starts, the more likely significant losses will occur. Infestations are rare in Wyoming with the possible exception of western Colorado. Chemical control of spider mites is difficult and seldom recommended.
White Grub, Phyllophaga spp.
White grub life cycles vary somewhat because some species complete their growth in one year and others require as much as four years. White grubs are large white C-shaped larvae with a brown head and legs. They feed on the roots of many types of plants. Problems from white grubs are most likely to occur when deans are planted after sod or grasses. In some cases, grass problems in alfalfa or corn may attract white grub adults to lay eggs.
Key Insect Management Strategies
Cultural Controls
Minimal stress during the growing season will encourage healthy crops and reduce the risks of pest infestation. Dry beans should not be planted near wheat crops due to problems with onion thrips.
Insecticides-
Pesticide: acephate (Orthene 75 S)
Pesticide: carbaryl (Sevin 4F)
Pesticide; carbaryl ( Sevin XLR Plus)
Pesticide: dicofol (Kelthane MF)
Pesticide: dimethoate (Cygon 2E)
Pesticide: disulfoton (Di-Syston 15% G)
Pesticide: disulfoton (Di-Syston 8)
Pesticide: endosulfan (Thiodan EC)
Pesticide: esfenvalerate (Asana XL, 0.66 EC)
Pesticide: malathion (Malathion 57 EC)
Pesticide: methomyl (Lannate LV)
Pesticide: methomyl (Lannate SP)
Pesticide: methyl parathion (Methyl Parathion)
Pesticide: naled (Dibrom 8E)
Pesticide: phorate (Thimet 20G)
Pesticide: phorate (Thimet 15G)
Key Weeds
Black nightshade, a member of the Nightshade family, is an annual that grows 6 - 24" tall with glabrous, appressed-hairy stems. Seed leaves of black nightshade are elongate-oval and pointed; the first true leaves are spade-shaped with smooth edges. Lower leaf surfaces are often purple. Berries turn from green to black when mature and the calyx covers only a small part of the fruit surface. Petioles, stems and leaves have some hairs but are not densely hairy or sticky. Leaves are ovate, smooth to wavy-edged and have a tapered tip. Flowers are white to pale blue, 0.25 - 0.4" wide borne in clusters. Flowering season is from May to October. Seed are the only source of reproduction.
Buffalobur, Solanum rustratum
Buffalobur, a member of the Nightshade family, is native to the Great Plains of the U.S. It is a drought tolerant species that can grow in a wide variety of environmental conditions. Buffalobur spreads exclusively by seed, which are enclosed within the spiny calyx. Buffalobur is an annual with spiny leaves, flowers, and stems, and grows up to 2' tall. Leaves are deeply lobed and up to 5" long. Flowers are 1" across, 5-petalled, and bright yellow, and are present on the plant from midsummer until frost. One of the five anthers in each flower is longer than the others. The fruit is a dry berry that is overgrown by the calyx, forming a bur-like fruit. Seed are black, flat and wrinkled.
Canada Thistle, Cirsium arvense
Canada thistle, a member of the Sunflower family, was introduced from Europe. It is a creeping perennial which reproduces by seed and fleshy, horizontal roots. Canada thistle is on the Wyoming noxious weed list. Stems are erect, hollow, smooth and slightly hairy, 1 - 5' tall, simple, and branched at the top. The leaves are set close on the stem, slightly clasping, and dark green. Leaf shape varies widely from oblong to lance-shaped. There are numerous sharp spines on the outer edges of the leaves, branches and main stem. The flowers are small and compact, about 0.75" or less in diameter, and light pink to rose-purple in color, occasionally white. The seed are oblong, flattened, dark brown, and approximately 0.125" long. Canada thistle emerges in April or May in most parts of Wyoming. Infestations are found in cultivated fields, riparian areas, pastures, rangeland, forests, lawns, gardens, roadsides, and waste areas. Because of its seeding habits, vigorous growth, and extensive underground root system, control or eradication is difficult. It is distributed across Wyoming in elevations ranging from 4,000 - 9,500'.
Common Lambsquarters, Chenopodium album
Common lambsquarters, a member of the Goosefoot family, was introduced from Europe. It reproduces by seed. The stem is erect, stout, smooth, grooved, often striped with pink or purple, branched and grows 1 - 6' high. Lower leaves are alternate and ovate. Upper leaves are also alternate, but are more narrow. The flowers are small, green and crowded in the axils and at the tips of the stems and branches. Common lambsquarters is a succulent, fast-growing plant which rapidly removes moisture from the soil.
Field Bindweed, Convolvulus arvensis
Field Bindweed, a member of the Morning-glory family, is a creeping perennial introduced from Europe. It reproduces by seed and horizontal roots. It is a serious problems for dry bean producers in the Southwest. Field bindweed is on the Wyoming noxious weed list. The stems are smooth, slender, slightly angled, 1 - 4' long and spread thickly over the ground or wind around erect plants and other objects. Leaves are alternate, 1 - 2" long, with great variation in shape. They are somewhat arrow-shaped with spreading, pointed, or blunt lobes at the base. Flowers are bell- or trumpet-shaped, white, pink, or variegated, and about 0.75 - 1" in diameter. Flowering is from June to September. Field bindweed is one of the most competitive perennial weeds. A two or three-year food supply is stored in the extensive underground root system. This makes it difficult to kill by cultivation because roots will live as long as their food reserve lasts. Seed remain viable in the soil for up to 40 years. Field bindweed is widespread in cultivated and uncultivated areas including pastures, lawns, gardens, roadsides, and waste areas throughout Wyoming from 4,000 - 8,000' in elevation.
Hairy Nightshade, Solanum sarrachoides
Hairy Nightshade, a member of the Nightshade family, is an annual. Leaves have wavy edges, prominent veins and numerous fine, short hairs, especially along the underside of the main vein. Berries are green or yellowish brown when mature, never black. The calyx covers the entire upper surface of the fruit. The pedicels, like stems and leaves, are usually hairy. Mature plants reach about 2' in height.
Jimsonweed, Datura stramonium
Jimsonweed, a member of the Nightshade family, is a rank-smelling annual. Stems are 0.75 - 5' tall. Leaves are alternate, large, usually unevenly toothed to shallowly lobed. Flowers are trumpet-shaped and 3.5 - 5" long. Jimsonweed has large leaves with spiny capsules that contain several hundred seed. As the capsule matures, it opens at the top and the plant tips it over, allowing all of the seed to fall out. The seed are potent hallucinogens, but are very toxic; several people have become seriously ill or have died from ingesting the seed.
Diffuse Knapweed, Centaurea diffusa
Diffuse knapweed is an annual, biennial, or short-lived perennial that can grow up to three feet high, with a single branched stem that gives the plant a bushy appearance. It is a serious problem in dry beans grown in the Southwest. Diffuse knapweed is on the Wyoming noxious weed list. Basal leaves of knapweed are pinnately divided and up to six inches long, while stem leaves are entire and smaller. Tips of each branch produce a third of an inch wide, white to pinkish flowers that appear midsummer to fall. Bracts surrounding the flower of yellowish green with a light brown comb-like margin. The upper part of each bract narrows into a short, stiff spine. Seed are brown to gray in color and are tipped by plumes that fall off at maturity. Several biological controls are available including a root boring beetle and moth, two seed head gall flies, and a seed head weevil, but none are proven effective yet.
Kochia, Kochia scoparia,
Kochia, a member of the Goosefoot family, is native of Eurasia. It is an annual, reproducing solely by seed. Flowering season is from July to October. Stems are erect, round, slender, pale green, branched, and 1 - 6' tall. Leaves are narrow, bright green, hairy, numerous and are attached directly to the stem. Upper leaves are more narrow than lower leaves. Flowers are inconspicuous in the upper leaf axils. Seed are about 0.063" long, wedge-shaped, dull brown, and slightly ribbed. Kochia can be found throughout Wyoming up to 8,500' in elevation. It has become a major problem on roadsides, waste areas, and non-cultivated fields. In the fall, plants become red, later turning brown and breaking away from the root, causing them to tumble over the ground scattering large amounts of seed. Many kochia populations in Wyoming are resistant to sulfonylurea, imidazilinone, triazine and benzoic acid herbicides, representing three very different modes of action. Therefore, care should be taken when using herbicides to control kochia. Some alternative herbicides include the following: fluroxypyr, bromoxynil, MCPA ester, isoxaflutole, pyridate, flufenacet, fomesafen, glyphosate, lactofen and clomazone. It is important to rotate herbicide modes of action to prevent future cases of herbicide resistance.
Pigweeds, Amaranthus spp.
Pigweeds, members of the Amaranth family, are weed pests in several cropping systems. A. hybridus, smooth pigweed, was the first triazine resistant plant documented. A. retroflexus, redroot pigweed, is probably Wyoming's most common species. A. lividus, is a prostrate species with a notch in the tip of the leaf. A. spinosus, spiny amaranth, has sharp, strong spines on the stem. A. graecizans, breaks off at the ground line and being round shaped is blown around by the wind. Redroot pigweed is ALS herbicide resistant.
Venice Mallow, Hibiscus trionum
Venice mallow, a member of the Mallow family, originated from Europe. It is an annual, typically growing 10 - 18" tall. Stems and petioles are usually covered with stiff hairs. Stems generally originate from a central base, and tend to be more spreading than erect. The showy flowers are light sulfur-yellow with a purple or blackish center, reaching up to 1.5" in diameter. Flowering season is from June to September. Seed are the only source of reproduction.
Additional Weeds
Barnyardgrass, Echinochloa crusgalli
Barnyardgrass, a member of the Grass family, is an annual that prefers wet sites. It is not usually a problem in well-drained cultivated fields but can grow heavily around irrigation pipe leaks and other wet spots in the field. It is a vigorous, warm season annual grass reaching 1 - 5' in height. Many stem bases are reddish to dark purple. Leaf blades are flat, broad, smooth, and without a ligule or auricle at the junction of sheath and blade. Seed are the only source of reproduction. It flourishes in warm conditions.
Common Cocklebur, Xanthium strumarium
Common cocklebur, a member of the Sunflower family, is a native weed. It is an annual, 2 - 4' tall, and stems are erect, branched, ridged, spotted, and very rough. Leaves are alternate, triangular or heart-shaped, rough on both sides, and long-petioled. Flowers are small and in axils of the upper leaves. Male and female flowers are separate. Flowering is from July to September. Fruits are 1" long, woody, with hooked prickles and two curved spines at the tip and two seed. The dark brown seed are flattened and have barbed hooks on the tips, allowing them to be easily distributed by wildlife. Seed are the only source of reproduction. It is a prolific seed producer and competes well with soybeans. New infestations appear around field edges or roadsides. Common cocklebur is especially abundant in areas where receding water has exposed previously submerged land. The burs are irritating both to humans and to animals.
Foxtail, Setaria spp.
Foxtail, members of the Grass family, is native to Eurasia, but common throughout most of North America. All foxtails bear seed in long, cylindrical panicles with crowded spikelets. These plants are responsible for reductions in yield, increased seed cleaning costs, and expensive control measures. Flowering and seed production occur from July to September. A primary control method for foxtail is the application of pre-emergence grass herbicides, which provide early season control.
Knotweed, Polygonum aviculare
Knotweed, a member of the Smartweed family, germinates earlier than most broadleaf weeds. It emerges in mid-March and is often mistaken for a grass because of its long, narrow cotyledons. It is an extremely variable annual with a wiry stem. Nodes are somewhat swollen, often surrounded with the torn remnant of a short, papery leaf sheath. Leaves are generally lance-shaped, blue green and alternate. Inconspicuous, greenish-white flowers are borne in the leaf axils. Knotweed thrives in dry compacted soils.
Purslane, Portulacca oleracea
Purslane, a member of the Purslane family, is a fleshy, prostate annual with smooth reddish or flesh colored stems. Branches radiate from a central rooting point, reach lengths in excess of 12" and form dense vegetative mats. Smooth, shiny, succulent leaves are somewhat teardrop-shaped, wider at the tip than at the base. Five petalled yellow flowers are borne singly in leaf axils, and open only in the sunshine. Extensive seed production throughout the growing season and its ability to re-sprout following cultivation makes this plant especially difficult to control.
Quackgrass, Elytrigia repens, syn Agropyron repens
Quackgrass, a member of the Grass family, is an aggressive perennial. It reproduces by seed or spreading by a shallow mass of long, slender, branching rhizomes. Quackgrass is on the Wyoming noxious weed list. Rhizomes are usually yellowish-white, sharp-pointed, somewhat fleshy. These rhizomes are effectively spread by tillage, increasing the distribution of the population in a field. They are able to penetrate hard soil or even tubers and roots of other plants. Stems are erect and usually 1 - 3' tall. Leaf blades are 0.25 - 0.5" wide, flat pointed and have small auricles at the junction of blade and sheath. Leaf sheaths and upper leaf blade surfaces are thinly covered with soft hairs. Spikelets are arranged in two long rows, flat wise to the stem. Florets either are awnless or have short, straight awns. Tillage is an effective control by depleting food reserves and bringing rhizomes to the surface.
Russian Thistle, Salsola iberica and S. collina
Russian thistle, a member of the Goosefoot family, was introduced from Russia. It is an annual and reproduces by seed. It is a round, bushy, branched plant growing 1 - 3.5' high. The branches are slender, succulent when young, and woody when mature. The first leaves to develop are alternate, dark green, soft, slender, and 1 - 2.5" long. These die early and new leaves form which are alternate, short, stiff, spiny, and not over 0.5" long, with two sharp-pointed bracts at the base. The flowers are small, inconspicuous, green-white or pink, and are usually solitary in the leaf axils. Seed are conical and 0.063" in diameter. Russian thistle grows in dry plains, cultivated fields, roadsides, and waste areas. At maturity, the plant breaks off at the base. Its round shape allows it to tumble, scattering seed for long distances. It is widespread over Wyoming in elevations up to 8,500'.
Sandbur, Cenchrus pauciflorus
Sandbur, a member of the Grass family, is a warm season annual with tufted stems. It grows 8"- 3' tall, occasionally erect, but usually spreading horizontally and forming dense mats. Leaf sheaths are flattened, very loose, and smooth with hairy margins. Burs are thickly set with stiff, sharp, spreading spines. They usually contain two light brown, oval to oblong seed.
Shattercane, Sorghum bicolor
Shattercane, a member of the Grass family, is an annual that often becomes a nuisance in cultivated fields. It probably developed from outcrossing with cultivated sorghum. Therefore, it is highly variable. Seed are the only source of reproduction. It is a major problem because seed are several inches deep and continue emerging throughout the summer. Shattercane flourishes in warm conditions. It usually requires post-emergence herbicides for control.
Sunflower, Helianthus annuus
Sunflower, a member of the Sunflower family, is a native weed. It is an annual, 1 - 10' tall. Stems are erect, simple to branched and rough. Leaves are alternate, simple, rough, and hairy. Ray flowers are yellow to orange-yellow and disk flowers are brown. Flowering is from July to September. Seed are the only source of reproduction.
Toothed Spurge, Euphorbia dentata
Toothed Spurge, a member of the Spurge family, is native to the Great Plains region. It spreads by seed and grows under a wide range of environmental conditions. Toothed spurge is an annual, growing up to 3' tall. Leaves are up to 3" long, ovate to linear, coarsely toothed, mostly opposite, hairy and often dotted with a few purplish-red spots. Stems are many branched and generally curve upwards. Both stems and leaves exude a milky latex material when broken. The inconspicuous flowers develop in late summer, followed by three sided, turban-shaped, 0.25", smooth, green fruits. Seed are rough, bumpy, oval and gray.
Velvetleaf, Abutilon theophrasti
Velvetleaf, a member of the Mallow family, was introduced from India and is an annual. It is completely covered with soft hairs, has erect stems, branching, and is 2 - 7' tall. Leaves are alternate, heart shaped, pointed at the apex, are 5" or more in width, and are attached to slender petioles. Flowers are solitary in the leaf axils with five yellow petals and numerous fused stamens that form a tube. Flowering and seed production occur from late June to October. Nine to fifteen rounded fruits are arranged in a disk, each containing three to nine seed that are egg-shaped, somewhat flattened, and rough gray-brown. The seed retain viability in soil for more than 50 years, making eradication difficult. Seed are the only source of reproduction.
Wild Buckwheat, Polygonum convolvulus
Wild buckwheat, a member of the Buckwheat family, is an annual weed with arrowhead shaped leaves. It has trailing stems that wind around other plants and is often mistaken for field bindweed. Its leaves are heart shaped, alternate and more pointed than those of field bindweed. The leaves have an inconspicious papery sheath that encircles the stem at the base of each petiole. Stems can be 8 - 40" long. In contrast to field bindweed, wild buckwheat has small, green flowers in the leaf axils. Seed are triangular, black and slightly roughened. Seed are the sole source of reproduction.
Wild Proso Millet, Panicum miliaceum
Wild proso millet, a member of the Grass family, is an annual, reproducing by seed. Although proso millet is grown in Wyoming as a crop, the wild species is very different. Seed germinate in the spring and throughout the summer when soil temperatures reach 68 F. Seed germinate and emerge from the soil as deep as 4" below the surface, but are equally able to germinate closer to the soil surface. Once in the soil, wild proso millet seed can remain viable for five or more years. Wild proso millet plants range in height from 1' in dry areas to 4 - 6' on irrigated sites. Stems of wild proso millet have abundant hairs located at right angles to the stem. As plants grow larger, they lodge and put down additional roots wherever stem joints touch the ground. Plants can begin flowering in July and continue throughout the summer. The inflorescence produced by wild proso millet is large and bushy. Seed matures in late August through September. Once mature, it readily shatters when the plant is disturbed. One wild proso millet plant per square foot in dry edible beans may produce 2,100 seed per square foot.
Key Weed Management Strategies
Cultural Controls
Minimal stress during the growing season will encourage healthy crops. Begin with high quality certified seed. Proper and timely preparation of the soil and seed bed prior to planting includes treating seed and destroying volunteer grains and beans. Thoughtful crop rotations and irrigation control will avert many weed problems. Recommended crop rotations are listed in the cropping systems section. Lay-by applications of Frontier may extend weed control. Tank mixing multiple herbicides/modes of action are important tools for suppressing resistant biotypes in dry bean weed populations. In the Southwest, more biological control releases are desired.
Herbicides-
Pesticide: alachlor (Lasso; Micro-Tech; Partner WDG)
Pesticide: bentazon (Basagran)
Pesticide: clethodim (Select 2 EC)
Pesticide: dimethenamid (Frontier 6.0)
Pesticide: EPTC (Eptam 20G)
Pesticide: EPTC (Eptam 7E)
Pesticide: ethalfuralin (Sonalan HFP)
Pesticide: glyphosate (many)
Pesticide: imazamox (Raptor)
Pesticide: imazethapyr (Pursuit)
Pesticide: paraquat (Gramoxone Extra)
Pesticide: pendimethalin (Prowl)
Pesticide: quizalofop (Assure II)
Pesticide: S-metolachlor (Dual II Magnum)
Pesticide: sethoxydim (Poast)
Pesticide: sethoxydim (Poast Plus)
Pesticide: trifluralin (Treflan HFP)
Pesticide: trifluralin (Treflan TR-10)
Critical Pest Management Issues
Disease problems are the most critical pest management issues for dry bean production. Therefore, fungicides and other disease management strategies are imperative to the continued success of dry bean production in Wyoming. Particularly nematodes and virus diseases are currently not being adequately managed.
There are no adequate controls for Canada thistle, cocklebur or field bindweed that do not cause pesticide damage to the dry bean plants.
ALS herbicide resistance can be selected for very quickly, even after two applications. More commonly, population pressure due to consecutive applications or continuous production of the same crop year after year using only ALS herbicides selects for resistance. In many situations, resistance is selected for along right-of-ways and then resistant biotypes move into agricultural fields. It is important to rotate not only herbicides when controlling weeds, but also herbicide modes of action to prevent future cases of herbicide resistance.
Weeds, diseases, and insects can all develop resistance over time to pesticides. When the same pesticide is used consecutively over a period of time, the target pest can become resistant to that pesticide and render the pesticide obsolete.
Key Diseases
Bacterial Brown Spot, Pseudomonas syringae pv syringae
Bacterial brown spot is a pathogen that affects the leaves, stems, pods, and seed of bean plants. Lesion size varies, but they are usually small and brown, surrounded by a narrow yellow zone. Water soaked tissue may not be noticeable, but if present it appears as small circular spots on the lower leaf surface. The centers of old lesions fall out, leaving tattered strips of holes on affected leaves. If the disease becomes systemic in the plant, lesions can occur along the stem. Pods from infected plants are bent or twisted with visual ring spots. Water-soaked brown lesions can form on pods. Older plants and plant parts are more resistant to infection. Rainstorms and sprinkler irrigation promote bacterial spread.
Bean Common Mosaic Virus, BCMV
Bean Common Mosaic Virus causes a systemic mosaic or darkening (necrosis) in susceptible plants infected by the virus. Symptoms appear as a green to bluish-green mottled or mosaic pattern on leaves which usually exhibit a downward curling or cupping. This mosaic symptom is often associated with virus and follows the network of leaf veins which become slightly darker than the areas between the veins. These symptoms are more easily observed by shading the leaf from direct sunlight. Severe, early infection greatly reduces plant vigor and productivity, and increases seed transmission. The virus is transmitted by aphids, mechanical damage, or by seed. In most cases there are resistant varieties. Virus-free seed should be used. Field sanitation, early planting, reflective mulches, a crop-free period, and vector control can be helpful.
Common Bacterial Blight, Xanthomonas campestris pv phaseoli
Small water soaked spots on the underside of leaflets are the first symptoms. These spots enlarge and merge, becoming dried and brown. A narrow, bright lemon-yellow border of tissue encircles the lesion. Infected pods develop circular water soaked spots and yellow masses of bacteria may appear at their center. Later, the spots dry and become reddish-brown sunken lesions. Early pod infection causes shriveled seed and the bacteria may cause yellowing to browning under the seed coat of infected seed. A stem girdling or joint rot occurs above the cotyledonary node of plants grown from infected seed. Planting infected seed favors early infection and disease spread. Warm weather also favors infection and symptom development. The bacteria survive in the field in infected seed. Planting beans on or next to a field blighted the previous year exposes the current season's crop to innoculum. The pathogen will spread from the surface of infected leaves and pods to healthy plants by storms, people, and machinery moving through the field when plants are wet. Rain, irrigation water, and hail also spread the pathogen within and between bean fields. Copper-based fungicides are effective in disease control. Management practices include the use of certified blight-free seed. If disease appears, machinery is kept out of the field during wet times to reduce spread of the bacterium. Beans are not be planted in infested fields for three years.
Fusarium Root Rot or Dry Rot, Fusarium solani f. sp. phaseoli
Fusarium root rot initially appears as red to reddish-brown streaks (lesions) on the hypocotyl and primary root 2 - 3 weeks after planting. These affected areas enlarge with age, may merge and gradually become brown by flowering. The symptoms may extend up the main root to the soil surface and longitudinal cracks can develop in older lesions. Severely infected primary and secondary roots are commonly killed but can persist on the plant as dried remnants. Lateral roots can develop from the hypocotyl above the initial infection site if sufficient soil moisture is available. Infected plants are stunted with yellow leaves but are seldom killed. The Fusarium root rot fungus occurs in most cultivated soils of the region where beans have been grown previously, and most plants grown in these soils will become infected to some degree before they mature. Root rot severity depends on factors such as cropping history, plant spacing, moisture, temperature stresses, and soil compaction. Early planting in soils that are cool and moist favors the disease, as does soil compaction in the form of tillage or hardpan layers. Controls are primarily cultural such as planting after the soils have warmed to 65F, eliminating moisture stress, deep tillage to remove compaction, spacing plants 2-3 inches apart, and tilling up soil around the base to encourage lateral root development above infected parts of roots. Tolerant varieties and rotation with non-host crops such as corn, wheat and barley are the recommended management strategy.
Halo Blight, Pseudomonas syringae pv. phaseolicola
Commonly, halo blight occurs simultaneously with bacterial brown spot, Pseudomonas syringae pv syringae, in Wyoming. The first symptom of infection is small water soaked spots on the leaflets. In a dry climate, this infected tissue dies and is tan-colored. A broad, yellow-green halo that surrounds the lesion helps distinguish halo blight from common bacterial blight which exhibits only a narrow, lemon-colored border around leaf lesions. Presence of halo blight is usually absent under high temperatures. Systemic infection causes younger leaflets to curve and exhibit considerable yellowing on these leaves with no dead spots or distinct halos. Halo blight symptoms on pods begin as water soaked circular spots which appear light cream or silver colored. Early pod infection causes shriveled seed. Stem girdling and joint rot occur above the cotyledonary node of plants grown from infected seed. Planting infected seed, or clean seed in the presence of infested debris in the area enhances early infection and disease spread. Cool weather favors the disease and production of the toxin that forms halos and systemic yellowing. Wet weather, hail, violent rainstorms and sprinkler irrigation enable the pathogen to be spread rapidly within and between fields. Older plants and plant parts are more resistant to infection. Resistant and tolerant varieties are available. Pathogen-free seed should always be used and/or treated seed with antibiotics to avoid external contamination. Crop rotation of two years out of beans and control of volunteer beans and weeds can enhance a control program. Foliar copper fungicides are effective as well.
Rhizoctonia Root Rot, Rhizoctonia solani
Rhizoctonia can cause seedling death, root and hypocotyl rot, stem canker, and pod rot. Initial symptoms appear on roots or hypocotyl as linear or circular reddish-brown sunken lesions of cankers delimited by a brown to reddish-brown margin. Over time, Rhizoctonia cankers enlarge, become darker, rough textured, and retard plant growth. The fungus can invade the central part of the lower stem and produce a brick-red discoloration. Disease symptoms often occur on scattered plants in a somewhat circular field pattern. Severe seedling infection causes plant death. Later in the season, mixed infection with the Fusarium and Pythium root rot organisms are common. Lesions may also develop on pods that are in contact with the moist soil surface and cause pod rotting or seed discoloration. Controls are primarily cultural such as planting after the soils have warmed to 65F, eliminating moisture stress, spacing plants 2-3 inches apart, and tilling up soil around the base to encourage lateral root development above infected parts of roots. Tolerant varieties, rotation with non-host crops such as corn, wheat, and barley, and treatment of seed or furrows with fungicides such as PCNB to delay infection are the recommended management strategies.
Rust, Uromyces appendiculatus
Rust symptoms first appear on the upper and/or lower surfaces of leaves as small yellow or white slightly raised spots. Green pods, and occasionally stems, also may become infected and develop typical rust-colored pustules. These spots enlarge and blister further to form reddish-brown or rust-colored pustules which are about 0.125" diameter and contain thousands of microscopic spores called urediniospores which allow the fungus to spread within and between fields. Pustules may be surrounded by a yellow border. Spores are readily released from the pustules and give a rusty appearance to anything they contact. Severe infections result in premature leaf drop. Pod set, and especially pod fill, can be reduced if infection is severe during early reproductive development of the bean plant. Near the end of the season, many pustules change color, and form dark brown to black teliospores which allow the fungus to overwinter in some production areas. Rust development is favored by cool to moderate temperatures less than 86 F with moisture conditions that result in prolonged periods of free water on the leaf surface. Rust overwinters in debris, can infect volunteer plants or are blown up from the south each year. Plant certified seed tolerant to rust and avoid using susceptible varieties. Bean volunteers are removed and plant debris incorporated into the soil following harvest. Fields are monitored for early infection and treated with fungicidal sprays such as chlorothalonil at first sign to lessen disease damage.
White Mold, Sclerotinia sclerotiorum
White mold initially appears on plants after flowering as water soaked spots on infected leaves, stems, branches, and pods. These areas enlarge into a watery rotten mass of tissue that becomes covered by a white fungal growth. Stem infection causes the part of the plant above the point of infection to wilt and die. Affected stems appear bleached and dry which differ from the tan color characteristic of mature, dry plant tissue. White mold development is influenced by prevailing weather conditions and certain cultural practices. High plant populations, narrow row widths, vigorously vining varieties, excessive fertilizers, and abundant irrigation or rainfall all favor the development of white mold. High humidity and a wet plant canopy and/or soil surface are necessary for spread. The disease may cause serious losses during wet, cool periods near the end of the growing season and even when the beans are in the windrow. This fungus produces sclerotia, survival structures which remain in the soil and are a source of new infections in subsequent years. Rotation for at least three years with non-host crops such as sugarbeets, alfalfa, corn, and small grains can reduce the number of sclerotia in the soil. Fungicides such as thiophanate methyl are applied at full bloom to protect flowers and reduce infection of pods. Seed can be treated to reduce incidence of infection.
Additional Diseases
Bean Yellow Mosaic Virus, BYMV
BYMV causes a systemic mosaic or darkening in susceptible plants infected by the virus. Symptoms appear as a green to a bluish-green mottled or mosaic pattern on leaves which usually exhibit a downward curling or cupping. This mosaic symptom is often associated with virus and follows the network of leaf veins. Veins become slightly darker than the areas between the veins. These symptoms are more easily observed by shading the leaf from direct sunlight. Severe, early infection greatly reduces plant vigor and productivity. BYMV is not seed transmitted. BYMV is harder to control than Bean Common Mosaic Virus due to the wide host range and only partial resistance to some but never all of the strains of the virus. It is transmitted into the field by aphids who have fed on infected neighboring plants.
Fusarium Wilt or Yellows, Fusarium oxysporum f sp phaseoli
Fusarium wilt is favored by high air and soil temperatures. This fungus overwinters in soil and plant debris. The first symptoms are drooping and epinasty (downward twisting) of leaves followed by yellowing, stunting and death. Symptoms may be one sided and progress upward killing foliage. A cross section of the stem near the base will have characteristic brown to reddish-orange vascular discoloration. Control is primarily through use of resistant varieties. Cultural controls such as planting after the soils have warmed to 65F, eliminating moisture stress, spacing plants 2-3 inches apart, and tilling up soil around the base to encourage lateral root development above infected parts of roots can help reduce the incidence of disease. Tolerant varieties and rotation with non-host crops such as corn, wheat, and barley are the recommended management strategies.
Pythium Damping Off, Wilt, and Pod Rot, Pythium spp.
Pythium may infect planted seed prior to germination, germinating seedlings, young plants, or older plants blossoming and forming pods. It is one of the pathogens capable of causing seed decay and seedling death. Initial root rot symptoms appear as elongated water soaked areas on the hypocotyl and roots, within one to three weeks after planting. The pathogen will extensively prune roots, reduce overall plant growth and destroy much of the hypocotyl and main root system. The water soaked area eventually dries out becoming somewhat sunken and tan to brown in color. Pre- and post-emergence damping-off and seedling blights occur in dry beans. Soil-inhabiting fungi such as Fusarium spp., Penicillium spp., Pythium spp., and Rhizoctonia solani can all cause these disease symptoms. Seedling blights occur after true leaves emerge. The developing root system rots and plants collapse. Seedling diseases are problems when soils are cold and wet at or immediately following planting. These conditions can delay germination or stress developing seedlings, which allows pathogens to attack. Crusting caused by poor soil preparation or hard rain, or excessive trash on the surface also contributes to disease. Fungicide seed treatment combined with avoiding cold wet soils and good soil preparation will best manage these diseases. Pythium species can be managed with fungicides such as metalaxyl and mefenoxam.
Key Disease Management Strategies
Cultural Controls
Minimal stress during the growing season will encourage healthy crops and reduce the risks of pest infestation. Begin with high quality certified seed and dry bean varieties that are resistant to pests. Proper and timely preparation of the soil and seed bed prior to planting includes treating seed with soil fungicides, destroying volunteer beans, and complete incorporation of previous crop residues. Thoughtful crop rotations and irrigation control will avert many pest problems; if the soil is too moist, it will encourage disease and mold, and the soil should be as dry as possible after pod formation. Recommended crop rotations are listed in the cropping systems section.
Priorities of management strategies for selected bean diseases:
| Fungal Diseases | Volunteer Control | Crop Rotation | Variety Selection | Good Seed | Planting Date | Tilage | Irrigation | Fertilization | Pesticide Schedule |
| Root Rots (Pythium, Fusarium, and Rhizoctonia) | L | H | M | L | H | H | M | M | M |
| Fusarium Wilt | L | H | H | L | H | H | M | M | M |
| White Mold | L | H | H | L | M | M | H | H | M |
| Rust | H | H | H | L | H | L | M | M | H |
| Anthracnose/ Angular Leaf Spot | H | H | H | H | M | L | M | M | H |
| Bacterial & Viral Diseases | Volunteer Control | Crop Rotation | Variety Selection | Good Seed | Planting Date | Tilage | Irrigation | Fertilization | Pesticide Schedule |
| Bacteria | H | H | M | H | M | L | M | M | H |
| Viruses | M | M | H | H | L | L | L | L | L |
H=High, M=Moderate, and L=Low Priority Disease Management
Fungicides-
Pesticide: benomyl (Benlate )
Pesticide: captan (Captan 30-DD)
Pesticide: captan (Captan 400)
Pesticide: carboxin (Vitavax 34)
Pesticide: chloroneb (Nu-flow D)
Pesticide: chloroneb (Chloroneb 65)
Pesticide: chlorothalonil (Bravo Ultrex)
Pesticide: chlorothalonil (Various trade names)
Pesticide: copper hydroxide (Champ Formula 2)
Pesticide: copper oxide (Kocide 2000, 4.5LF)
Pesticide: maneb (Manex)
Pesticide: maneb (Maneb 75 DF; Maneb 80WP)
Pesticide: metalaxyl (Apron Flowable)
Pesticide: metalaxyl (Apron XL)
Pesticide: mefenoxam (Ridomil Gold EC)
Pesticide: mefenoxam (Ridomil PCGR)
Pesticide: PCNB (Terraclor 75WP)
Pesticide: PCNB (Terraclor Flowable)
Pesticide: PCNB (Terraclor 10G)
Pesticide: PCNB (Terraclor 15G)
Pesticide: PCNB (RTU-PCNB)
Pesticide: PCNB + captan (Rival)
Pesticide: propiconazole (Tilt)
Pesticide: sulfur (Super Six Liquid Sulfur)
Pesticide: thiophanate methyl (Topsin M WSB; Topsin M 70WP)
Pesticide: thiram (Thiram 42S)
Mark A. Ferrell Extension Pesticide Coordinator Weed Scientist University of Wyoming College of Agriculture - Plant Sciences Department 3354 1000 E. University Avenue Laramie, WY 82071-3354 office: (307) 766-5381 fax: (307) 766-5549 email: ferrell@uwyo.edu webpage: http://www.uwyo.edu/plants/wyopest/home.htm
Authors
Sandra K. McDonald, Editor