There are many common species of solitary bees that nest in individual holes in the ground. These bees range in size from « to 3/4 inches long and may be blue, green, copper or metallic reddish-brown. They may belong to one of several groups of bees such as the membrane bees, digger bees, sweat bees, mason bees and leafcutter bees (Colletidae, Andrenidae, Halictidae, Anthophoridae, Megachilidae) and occur across the state. During the evening hours, females excavate nesting burrows that reach six or more inches in depth. Some of these bees line the burrow with a water-proofing secretion for protection from moisture. Small mounds of excavated soil may appear around each nest opening. When bees are numerous, many holes may be in close proximity, creating a "citylike" aggregation. Each hole belongs to an individual female. During the day, the active females collect pollen and nectar to carry back to the nest to form a "ball" 1/8 to 1/4 inch in diameter that is placed within a "cell" excavated in the side of the burrow. A single egg is laid upon the pollen ball in March, April or early May. After hatching, the larva feeds on pollen and develops within the cell into a new generation of bees. The new generation emerges the following year in March or April. At this time, mating takes place and bee activity begins to pick up as the nesting cycle resumes. Though adult bees feed on nectar, none store honey as such. Solitary, ground-nesting bees play a vital role in ecological systems, especially in pollination of crops and wild plants. Solitary bees are valuable pollinators and should not be destroyed unless there is some compelling reason.
Ground-nesting bees generally prefer nesting in areas with morning sun exposure and well-drained soils containing little organic matter. Burrows are excavated in areas of bare ground or sparse vegetation. These bees usually avoid damp soils. Damage to lawns and turf is usually minimal, but control is often sought because the bees are misperceived as a danger or annoyance.
Solitary bees rarely sting and there is no mass attack as might occur with honey bees or yellow-jackets. Mowing and other outdoor activities can be continued with little problem. However, avoid areas with very large aggregations for 4 to 6 weeks while nesting is taking place.
Cultural control methods include heavy watering or irrigation with a lawn sprinkler during the nest-building period to discourage nesting. Tilling of soil to destroy tunnels may help a little, but establishment of dense turf is probably the best discouragement to further nesting. Applications of heavy organic matter could be included as a soil amendment, if practical, when tilling the soil. If the soil or location is not conducive to a healthy lawn, using ground covers or heavy mulches may be an alternative solution. Mulches may be used on bare patches caused by heavy traffic where grass will not grow.
Description
Adult. When resting, cutworm moths hold their wings back in a triangular position. The moths are generally stocky and have a wingspan of about 40 mm. The forewings are dark brown and mottled or streaked; the hindwings are lightly colored and unmarked.
The eggs are usually white (becoming darker prior to hatching), round, and 0.5 to 0.75 mm in diameter.
Larva. If disturbed, the larvae usually curl into a C-shaped ball. Cutworms are fat, smooth, dull-colored caterpillars that measure about 45 mm when fully grown.
Pupae are brown and 15 to 22 mm long.
Biology
Cutworms are found throughout the United States. In addition to field and vegetable crops, cutworms also attack most turf grasses. Many cutworms prefer wilted plant material and sever the plants sometime prior to feeding. Stems are chewed near the soil. Some cutworms climb the host and feed on unopened buds.
Although there are many important species of cutworms, the black, granulate and variegated cutworms are the ones most commonly encountered on North Carolina turfgrass. Each species differs slightly from the others in details of habits and appearance, but their life histories are generally similar. Adults and larvae are nocturnal and hide during the day, although they may become active on cloudy days. The overwintering forms of cutworms occur in the soil either as pupae or mature larvae. In the spring, the hibernating larvae pupate. Adults begin to appear in the middle of March. Female moths deposit eggs singly or in clusters, and each female can lay as many as 500 eggs. Under optimum conditions, the eggs hatch in 3 to 5 days, and larvae develop in 3 to 4 weeks, passing through six instars. Pupae mature in two weeks during the summer and as many as nine weeks in the fall. Some of the cutworms can produce as many as four generations each year in North Carolina.
Control
For chemical control, consult the currentNorth Carolina Agricultural Chemicals Manual.
Description
Adult. The moth has a wingspan of about 38.5 mm. The hind wings are white; the front wings are dark gray, mottled with lighter and darker splotches. Each forewing has a noticeable whitish spot near the extreme tip.
Minute, light gray eggs are laid in clusters and are covered with grayish, fuzzy scales from the body of the female moth. The eggs become very dark just before hatching.
The mature green, brown, or black larva, 35 to 50 mm long, has a dark head usually marked with a pale, but distinct, inverted "Y." Along each side of its body is a longitudinal, black stripe. There are four black dots on the dorsal side of each abdominal segment.
The pupa, approximately 13 mm long, is originally reddish brown and darkens to black as it matures.
Biology
The fall armyworm is a continuous resident of the tropics of North, Central, and South America, and some of the West Indies. With mild winters, it may persist year round along the Gulf Coast of the southern states. Each year it migrates as far north as Montana, Michigan, and New Hampshire.
The fall armyworm has a wide host range but prefers plants in the grass family. Most grasses, including coastal Bermudagrass, fescue, ryegrass, bluegrass, Johnsongrass, timothy, corn, sorghum, Sudangrass, and small grain crops, are subject to infestation. Fall armyworms, often migrating in large armies, are potential turf and pasture pests in late summer and fall. Consuming all above-ground plant parts, they are capable of killing or severely retarding the growth of grasses.
Fall armyworms probably overwinter as pupae in the Gulf Coast region of the United States. Egg-laying moths migrate northward throughout the spring and summer and arrive in North Carolina during mid-July. New moths may continue to appear into November. Each female lays about 1,000 eggs in masses of 50 to several hundred. Two to ten days later the small larvae emerge, feed gregariously on the remains of the egg mass, and then scatter in search of food. Unlike the nocturnal true armyworms, fall armyworms feed any time of the day or night, but are most active early in the morning or late in the evening. When abundant. these caterpillars eat all the food at hand and then crawl in great armies to adjoining fields. After feeding for 2 to 3 weeks, the larvae dig about 20 mm into the ground to pupate. Within two weeks, a new swarm of moths emerges and usually flies several miles before laying eggs. Several generations occur each year in North Carolina.
Control
During favorable seasons, a number of parasitic enemies keep fall armyworm larvae down to moderate numbers. Cold, wet springs seem to reduce the effectiveness of these parasites and allow large fall armyworm populations to develop. The fall armyworm is more difficult to control chemically than the true armyworm. For specific control information, consult the current North Carolina Agricultural Chemicals Manual.
Description
Adult. About 1.6 mm long, the adult female is a pinkish scale insect with well-developed forelegs and claws. The male is a gnat-like insect varying from 1 to 8 mm in length.
Clusters of pinkish-white eggs are enveloped in a white waxy sac.
Commonly referred to as a ground pearl, the slender nymph is covered with a hard, globular, yellowish-purple shell. An encysted nymph varies from 0.5 to 2.0 mm in diameter.
Biology
Ground pearls are potentially serious problems in both southeastern and southwestern states. The roots of Bermuda, St. Augustine, zoysia, and centipede grasses are most commonly infested with ground pearls. The ground pearl nymphs extract juices from underground plant parts. The damage is most apparent during dry spells when irregularly shaped patches of grass turn yellow. The grass in these spots eventually turns brown and usually dies by fall.
Overwintering takes place in the ground pearl stage. Females usually reach maturity in late spring and emerge from their cysts. After a brief period of mobility, the wingless females settle 5 to 7.5 cm. deep in the soil and secrete a waxy coat. Within this protective covering, females develop eggs (without mating) and deposit them through-out early summer. Approximately 100 eggs are laid by each female. The slender nymphs emerge in mid-summer and infest grass rootlets. Once they initiate feeding, nymphs soon develop the familiar globular appearance. There is usually one generation each year. However, if conditions are not favorable for emergence, female nymphs may remain in the ground pearl stage for several years.
Control
Insecticides have not been effective against ground pearls. Good cultural practices, such as watering and fertilization may help lawn grasses recover from injury, but such beneficial effects may be only temporary. For recommendations, consult the current North Carolina Agricultural Chemicals Manual.
Description
Billbugs are brown to black hard-shelled, snout beetles usually covered with clay or soil particles. They vary in length from 5 to 11 mm, depending on the particular species.
The elongate, creamy white eggs are 2 to 3 mm long and turn yellow before hatching.
The white, legless grubs have hard, yellowish- or reddish-brown heads. When mature, these larvae vary from 9 to 16 mm in length.
The pale yellow or white pupae are similar to adults in size and shape.
Biology
The hunting billbug occurs along the eastern seaboard from Maryland to Florida. It has also been reported in California and Hawaii. Most species of grasses are subject to billbug infestation. However, hunting billbugs prefer zoysia and Bermuda grasses.
Both larvae and adults injure turf grasses. The larvae are root feeders; the beetles eat leaves and burrow in stems near the surface of the soil. Variously shaped, yellow or brown patches appear in infested lawns. The symptoms may resemble fertilizer burn. However, in the case of billbug infested lawns, tufts of discolored grass can be easily pulled up (unlike grass burned by fertilizer).
In the southern states, billbugs may overwinter in any life stage, although adults are best able to withstand severe winters. Emerging in the spring, adults feed and mate. Females place eggs in cells cut into grass stems. Two days to 2 weeks later, larvae appear and work their way down from the inner leaves to the root system. They feed for 3 to 5 weeks before pupating in cells in the soil. The pupal period lasts 3 to 7 days. Afterwards, the new adults may remain in the pupal cells to overwinter or may emerge and be active until the onset of cold weather. One generation is completed each year.
Control
A commonly used economic threshold for billbug control consists of 107 to 140 larvae per square meter (10 to 14 per square foot). For infestations of this intensity, apply an insecticide drench that will penetrate the soil and reach the grubs. For recommended insecticides and rates, consult the current North Carolina Agricultural Chemicals Manual.
Description
Leafhoppers average 7 mm in length (rarely as long as 13 mm). They have a triangular, often elongated, head and may be yellow, green, or gray. Some species are mottled and speckled.
The white, elongate eggs are 1 mm or less in length.
The pale, wingless nymphs are smaller than adults but similar in shape.
Biology
Leafhoppers are common throughout the eastern United States and occur in all areas of North Carolina. Leafhoppers infest several hundred kinds of cultivated and wild plants. Leafhoppers retard the growth of grass by piercing stems and leaves with their needle-like mouthparts and extracting sap. This type of feeding causes infested areas to have a whitened or bleached appearance. This symptom can be mistaken for drought or disease damage. Newly seeded lawns are sometimes killed by leafhoppers.
Leafhoppers may overwinter as eggs or adults. Resuming activity in the spring, the adults begin to feed and mate. Females insert 75 to several hundred eggs, singly, into the leaf veins of tender new foliage. About 10 days later, nymphs emerge. Over a period of 12 to 30 days, these immature leafhoppers feed on new leaves and develop through five instars. The fully grown nymphs then molt to become adults and the life cycle is repeated. Leafhoppers produce one to four generations each year depending on the latitude and the particular leafhopper species.
Control
Leafhoppers can be chemically controlled, but treated areas may be reinfested from untreated areas. Therefore, if populations are high, sprays may have to be repeated at 4- to 5-week intervals throughout the growing season. For specific insecticides and rates, consult the current North Carolina Agricultural Chemicals Manual.
MOLE CRICKETS
Photo courtesy of Dr. Jim Baker, Extension Entomology Specialist
The adult is covered with fine hairs which give it a velvety appearance,. The 3.8 cm long, brown mole cricket has beady eyes and stout, shovel-like front legs for digging.
The greenish, oval egg is about 3.2 mm long.
Although wingless and slightly smaller, the nymphs resemble the adult in shape.
Biology
Thriving best in moist, light soils, mole crickets are common in Coastal Plain areas from North Carolina to Texas. They are particularly attracted to soil containing manure or rotting crop debris. Their vertical distribution in the soil varies with temperature and moisture. Although they have a wide host range, mole crickets are particularly damaging to the underground plant parts of vegetable crops, tobacco, peanuts, strawberries, and grasses. They are potential problems in seedling turfs and in established bahiagrass. Burrowing in the soil, mole crickets feed at night on roots, stems, and tubers. The burrows cause the soil to dry out, thereby affecting plants that are not actually fed upon. Some plants may be uprooted, but turf usually dies from root damage and drought. Small numbers of mole crickets are capable of extensive damage especially on newly seeded turf. One mole cricket may cover several meters (or several yards) each night. On golf greens, the raised tunnels made by mole crickets are skimmed off by the mower.
Mole crickets generally overwinter as nymphs 7.5 to 25.0 cm (3 to 10 in) deep in the soil. These nymphs become active in March and feed until they mature in late spring. In May or June, the new adults emerge from the soil and are attracted to lights as they engage in mating flights. Eggs are laid in the soil in cells constructed by the females. Approximately 35 to 50 eggs are placed in each cell. Hatching occurs in 10 to 40 days depending on temperature. Nymphs develop through eight instars and may become adults by winter or may overwinter as immatures. One generation occurs each year.
Control
Mole crickets are controlled with contact insecticides or poisoned baits. On established turf, spray or granular applications can be used as long as they are thoroughly watered into the grass. Such treatments will be most effective if they are applied when night temperatures are at least 15ºC (about 60ºF). However, as more pests migrate into the area, another application may be necessary. Poisoned baits are most effective in August or September when the young nymphs are hungry. Consult the current North Carolina Agricultural Chemicals Manual .
Scientific Name: Blissu Insularis
Description
The adult chinch bug is about 4 mm long and black with opaque wings. The wings may be as long as the body or only 1/3 to 1/2 the length of the body. In any case, each wing bears a distinctive triangular, black mark.
Each egg, approximately 0.84 by 0.30 mm, is flattened at one end, that end bearing three to five minute projections. Its color gradually changes from pale yellow to red before hatching.
The wingless nymph is smaller than but similar in shape to the adult. The head and thorax are brown; the eyes are dark red; and the abdomen is pale yellow or light red with a black top.
Biology
The southern chinch bug is common throughout the Gulf states and into Georgia and North and South Carolina. It is primarily a problem on thick mats of turf in sunny, open areas. The southern chinch bug is commonly a problem on St. Augustine grass but also infests pangola, torpedo, centipede and occasionally Bermuda grasses. Chinch bug populations are concentrated near the surface of the soil. The nymphs which extract plant juices with their needle-like mouthparts are primarily responsible for lawn damage. On St. Augustine grass, feeding is primarily restricted to the tender basal area of the grass blades and to the nodes of runners. As the nymphs feed, yellowish spots which soon become brown dead areas appear in the grass. As the grass dies, the nymphs move to the periphery of the dead spots thereby causing them to enlarge. Chinch bug damage is greatest during hot, dry weather.
Except in southern Florida where they remain active year round, southern chinch bugs overwinter as eggs. The eggs are usually found inserted in crevices at grass nodes or between overlapping leaf blades. The eggs hatch in spring, releasing nymphs which subsequently infest lawns. Nymphs feed and develop for 2 to 6 weeks depending on weather conditions.
The new generation of adults causes little damage. Each female however, deposits 100 to 300 eggs which hatch two weeks later. With three to five chinch bug generations each year (depending on latitude), lawns may be infested from spring through late fall.
Control
During cool, cloudy weather, chinch bugs are attacked by a fungal disease. If the weather is hot and dry, the operation of a sprinkler system helps prevent chinch bug damage. Chinch bugs should be controlled chemically if they are readily apparent on the soil surface when grass plants are spread apart. Infested turf should be thoroughly watered before application in the case of spray formulations and at application in the case of granules. For currently recommended insecticides and rates, consult the current North Carolina Agricultural Chemicals Manual .
SOD WEBWORM
Photo courtesy of Dr. Jim Baker, North Carolina State University
The moths, 13 to 19 mm long, have a wingspan of about 15 to 35 mm. They have a prominent forward projection (labial palps) on the head. The forewings are brown or dull ash gray, with a whitish streak from the base to the margin; the hindwings are brownish. When at rest, the moth fold its wings in a tent-like manner over the body.
The tiny, oblong eggs are white to pale yellow. Each egg is about 0.5 mm long and 0.3 mm wide.
Most larvae vary from pinkish white to yellowish to light brown. They are 16 to 28 mm long when fully grown, with thick bodies, coarse hairs, and paired dorsal and lateral spots on each segment. The head is yellowish brown, brown, or black. Individual grubs often assume a C-shaped position. Tropical sod webworms are greenish and up to 19 mm long.
The reddish-brown pupae are 11 to 13 mm long.
Biology
Many species of sod webworms occur in the United States. The actual species present in any given area, however, is highly variable. Whereas many Crambus spp. are generally distributed, the tropical sod webworm is common primarily in Florida and Pediasia trisecta abounds in Tennessee.
Sod webworms feed on lawns, golf course grasses, some clovers, corn, tobacco, bluegrass, and timothy, as well as pasture and field grasses. They usually favor bluegrass and Tifdwarf hybrid Bermudagrass, but will attack most grasses.
Larvae cut off grass blades just above the thatch line, pull them into their tunnels and eat them. The injury appears as small brown patches of closely cropped grass. If many larvae are present, the patches run together to form large, irregular brown patches.
Webworms overwinter as young larvae a few centimeters below the soil line among the roots of weeds and grasses in silk-lined tubes. During early spring the larvae feed on the upper root systems, stems, and blades of grass. They build protective silken webs, usually on steep slopes and in sunny areas, where they feed and develop. In early May, they pupate in underground cocoons made of silk, bits of plants, and soil. About two weeks later, adults emerge. Beginning in May, moth flights may occur until October. The moths, erratic and weak flyers, live only a few days and feed solely on dew. They are active at dusk, resting near the ground in the grass during the day.
The eggs, which are deposited indiscriminately over the grass, hatch in 7 to 10 days. Young larvae immediately begin to feed and construct their silken tunnels. The most severe damage occurs in July and August when the grass is not growing rapidly. During this hot weather, the larvae feed at night or on cloudy days. Most sod webworms complete two or three generations each year, with approximately six weeks elapsing between egg deposition and adult emergence. In Florida, tropical sod webworms may produce a new generation every 5 to 6 weeks. A sod webworm infestation in the lawn can be detected by applying 1 tablespoon of pyrethrin (insecticide) in 1 gallon of water per square meter (or square yard). The caterpillars will surface within a few minutes and can be found by separating the blades of grass, particularly at the interface between living and dead areas of turf. If three or four webworms are found in a 15 cm square (6-inch square) area, control is recommended.
Control
For specific chemical control, consult the current North Carolina Agricultural Chemicals Manual .
Description
The black, leafhopper-like adult is 6 to 10 mm long and has two red or orange lines across the wings. Its eyes are dark red.
The bright yellow orange, oblong egg is pointed at one end and measures about 1 mm long. Red and black areas develop before hatching.
The wingless nymph resembles the adult in shape, but is slightly smaller. Enveloped in a white, frothy mass, this red-eyed immature form may be yellow, orange, or white with a brown head.
Biology
The two- lined spittlebug occurs from Maine to Florida and westward to Iowa, Kansas, and Oklahoma. This spittlebug feeds on many crops, ornamentals, and weeds in addition to turf grasses. Ornamental and weedy grass hosts include Coastal Bermuda, St. Augustine, centipede, pangola, bahia, ryegrass, crabgrass, Johnsongrass, and orchard grasses. Plants commonly infested by adults are holly, redbud, aster, gerbera, blackberry, pea, peach, honeysuckle, morning glory and most small grain crops.
Spittlebugs are rarely a problem on well-managed turf. Both nymphs and adults extract plant juices through their needle-like mouthparts. Such feeding by large numbers of spittlebugs may kill, wither, or check the growth of turf grasses.
Two- lined spittlebugs overwinter as eggs in hollow stems, behind leaf sheaths, or among plant debris. Emerging in the spring, the nymphs seek sheltered, humid, hiding places among plants and begin feeding. Soon they exude a white, frothy "spittle" mass which protects them from natural enemies and desiccation. After feeding for at least a month and developing through four instars, nymphs become adults. Most active in early morning, spittlebugs spend the warmer hours of the day hiding deep in the grass. Adults live about 23 days and females spend the last two weeks of this period depositing eggs. Hatching occurs about two weeks later. Two generations occur annually in North Carolina.
Control
Control measures for spittlebugs in lawns are seldom necessary. Should a serious infestation occur, chemical controls are available. For recommended insecticides and rates. consult the current North Carolina Agricultural Chemicals Manual.
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