Ornamental Plantings | Turfgrass & Lawns

ANTS

 

Several species of ants commonly inhabit home lawns and ornamental plantings of trees and shrubs. Winged ants are frequently confused with swarming termites. Ants can be easily distinguished from termites by the following characteristics: (1) ants have elbowed antennae while those of termites are straight and beadlike; (2) front wings of ants are larger in size than the rear wings while those of termites are all equal in size; (3) the waist of ants are thin and appear to be constricted while those of termites are broad and not constricted; (4) wings of ants are usually transparent or brownish while those of termites are milky-white.

 

DESCRIPTION

 

Little Black Ant: Workers of this species are 1/10-1/8 inch in length with soft jet-black bodies. These ants are found primarily in soil and rotting wood. They feed on a wide variety of food sources.

The Pavement Ant: These ants are slow, sluggish, short-legged, and usually nest under pavements and foundations. They are 1/12-1/4 inch in length and brownish-black. They feed on a wide variety of food sources (seeds, grease, animal food).

Cornfield Ant: These ants are usually found nesting in open places in the soil or in rotten wood. They are 1/8-1/4 inch in length, robust, soft-bodied, and light to dark brown. The body, when crushed, has an acid (formic) odor. These ants are found feeding on seeds, and often are associated with aphids and mealybugs which are excreting honeydew.

Larger Yellow Ant: These ants are 1/10-1/8 inch in length and yellow. When crushed they give off a characteristic lemon-verbena odor. They are common soil inhabiting species which tend mealybugs and aphids on the roots of plants.

LIFE HISTORY

Ants form colonies or nests where queens remain. Most ant species have only one queen per nest; she lays the eggs needed to maintain or increase the colony. Queens may live from 1-15 years and produce many thousands of eggs.

Larvae, or maggot-like grubs, hatch from the eggs. They are transparent white, soft-bodied, and legless. These larvae, along with the queen, are fed by the worker ants (foragers). Larvae pass through several molts before pupation and adulthood are reached. The majority of these develop into workers; a few develop into winged males and females which are the kings and queens of the ant colony. At certain times during the year (usually early spring and late summer), varying with the species, these winged ants leave the nest and swarm. Females and males mate and the males die soon after. The mated female (queen) flies to an attractive nesting site, tears off her wings, and encloses herself in a small excavation in the soil, and lays eggs. She feeds and cares for the first generation of progeny until they are mature adults. After that they and succeeding generations care for her. She remains in the nest and continues to produce eggs the remainder of her life.

DAMAGE

Ants seldom cause serious damage to home lawns. They may cause minor damage to the turf by loosening the soil and constructing small mounds in the nesting areas. Ants also feed on honeydew (sticky sugary substance) excreted by aphids, mealybugs, and soft scales. Homeowners may become alarmed when ants swarm during spring and late summer because they associate swarming insects with termites. However, if they examine specimens for the above differentiating characters, confusion should be eliminated. Respect these small insects since they do bite and some can also sting. Many ants are considered beneficial because they are scavengers and predators on certain harmful insects.

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Armyworm Native to North America, the armyworm can be found east of the Rocky Mountains, reaching northward into southern Canada. Armyworms get their name from their behavior of moving across fields in an army-like fashion. As larvae consume available food sources, they migrate as an army to new host plants. Though they feed primarily on grasses (oats, wheat, fall rye, corn, barley, and forage grasses), they can be a pest of some vegetables (bean, cabbage, carrot, onion, pea, pepper, radish and sweet potato). There are usually two to three generations each year in Illinois.

Armyworm larva

Description Armyworm larvae vary in color from dark greenish-brown to black. On each side, there are long, pale white, orange, and dark brown stripes along the length of the abdomen. Mature larvae are approximately 1 ˝ inches long. The head capsule is yellowish brown with a brown network of veins, giving it a mottled appearance. Armyworm larvae may also be distinguished by a dark band on the outer side of each proleg. Armyworm pupa stay in a brown earthen shell just below the soil surface. The armyworm moth, approximately an inch long with a 1 ˝ inch wingspan, is tan to light brown, with a tiny white spot centered on each forewing. Eggs, which resemble small white globules, are laid in rows or groups on leaves of host plants. After oviposition, the moth rolls the leaf blade of the plant around each egg mass.

Life Cycle Few armyworms overwinter in Illinois. Most armyworm moths migrate into the Illinois from the southern states in April and May. During the day, moths remain hidden in grassy vegetation. Armyworm moths are active during the evening, feeding on nectar, mating, and searching for oviposition sites. Eggs are deposited in rows or clusters on thelower leaves of grasses or at the base of plants. Eggs hatch in1 to 2 weeks. Newly hatched larvae are pale green and move in a looping motion. Larvae are also active at night, feeding on host plants. During the day, they can be found under plant debris or in the top few inches ofthe soil. After completing six instars, larvae pupate just below the soil surface. Adults emerge in 1 to 2 weeks. A second generation occurs in late June or early July and a third in late August or early September.

Injury Since moths prefer dense vegetation for oviposition sites, armyworm infestations generally develop in areas such as grass pastures, roadsides, and along fence rows. Oviposition sites often include weeds and grassy in weedy or reduced tillage fields. Consequently, these fields armyworms are often a problem in these fields. If a herbicide is used to control the weeds, larvae move from the dead grasses to the corn. As larvae run out of available food sources, they move to other host plants such as small grains and corn. This usually occurs during May and early June. Armyworms consume leaf tissue of corn plants. Feeding is usually confined to leaf margins, but in some instances, larvae may strip the plants entirely of leaf tissue. Corn generally recovers from damage caused by moderate infestations if the growing pointhas not been injured. Ordinarily armyworms that attack young corn migrate from small grains or grass fields.

Armyworm larvae chew the leaves of small grains and grasses. They may strip the leaf margins and move up the plant to feed on the panicles or flowers. Larvae will feed on the flag leaves, kernels, and clip the stems just below the heads. Injury caused by armyworms in forages is sometimes confused with that caused by other insects. Armyworms do not attack pure stands of alfalfa and other legumes, but cutworms do feed on these crops. If the field is a grass-legume mixture, cutworms and armyworms may both be present. If it is a pure grass stand, the insects are probably armyworms. The damage is the same, however, as both eat the foliage. Oftentimes groundhogs, rabbits, mice, and other small animals will cut stems of plants into small sections and pile them up. All of the plants in a small area may be cut up into tiny sections. Many people mistake this for armyworm damage. BACK TO TOP

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Billbugs

David J. Shetlar

Billbugs are weevils that have the snout, head and thorax about as long as the wing covers. Though there are about a half dozen species that may be found in turfgrasses, only a few cause damage in any given region. The most common pest in Ohio is the bluegrass billbug, Sphenophorus parvulus Gyllenhal, though the lesser billbug, S. minimus Hart, is somewhat common. The adults are only 1/4- to 3/8-inch long and dark grey to black. They may be covered with a tan or brown coating of soil. The larvae are white with a brown head and look like legless white grubs.

Figure 1. Bluegrass Larva

The bluegrass billbug is most common in the northern states from New England to Washington state. It is found less commonly in southern states. Both billbugs seem to prefer Kentucky bluegrass-growing regions.

Figure 2. Bluegrass Billbug Adult

Kentucky bluegrass seems the preferred host but occasionally this pest has infested perennial ryegrass, red fescue and tall fescue. It also attacks small grain crops such as corn, rye and wheat.

Types Of Damage

Billbug damage usually appears in late-June through August, when summer drought stress is common. Light infestations in lawns often produce small dead spots that look like the turf disease, dollar spot. Sometimes the damage looks like irregular mottling or browning in the turf. Heavy infestations can result in complete destruction of the turf, usually by August. The major problem with billbug damage is that it looks like a variety of other problems. Most turf managers confuse billbug damage with drought, disease, chinch bugs, greenbugs or white grubs. Billbug damaged turf turns a whitish-straw color rather than the yellow caused by greenbugs. Soil under damaged turf is solid, not spongy as in white grub attacks.

To confirm billbug attacks, grasp the affected turf and pull upward. If the stalks break easily at ground level and the stems are hollowed out or are full of packed sawdust-like material, billbugs are the culprit.

Life Cycle And Habits

In most of the Kentucky bluegrass growing regions this pest overwinters in the adult stage. Adults have been found in thatch, cracks and crevices in the soil, worm holes and in leaf litter near turf. The hibernating adults become more active in late-April to mid-May when the soil surface temperatures rise above 65 degrees F. The adults wander in search of suitable grasses and crops on which to feed. After feeding for a short period, the female begins to insert one to three eggs in a feeding hole made in grass stems. The females may continue laying eggs into August but most eggs are laid by early-July. Laboratory kept females have been known to lay over 200 eggs, usually two to five per day. The eggs hatch in six days depending on the temperature and the young larvae begin to tunnel up and down the stem. If a stem is hollowed out while the larva is small, an exit hole may be formed and the larva will drop out and bore into another stem. Eventually the larva becomes too large to fit inside the grass stems. They then drop to the ground to begin feeding externally on the grass crowns and roots. This is the point at which significant damage to the turf is noticed, especially if little rainfall or irrigation has occurred at this time. After 35 to 55 days, the larva is full grown and pupates in a cell of soil under the thatch. The pupa gradually darkens and the reddish-brown, tineral adult emerges in 8 to 10 days. The new adults appear to be common in late-August through September. These adults do some minor feeding and seek out suitable sites for overwintering. Some adults have been observed trying to fly but no great distances were covered. There is some evidence that adults which emerge early in August may begin laying eggs for a partial second generation. These larvae often do not develop rapidly enough to mature before freezing temperatures arrive.

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Chinch Bugs

David J. Shetlar

There are several chinch bugs that attack turfgrasses in North America. The hairy chinch bug, Blissus leucopterus hirtus Montandon, is the most commonly encountered pest of northern turfgrasses though the common chinch bug, Blissus leucopterus leucopterus Say, is occasionally found. These closely related pests are very difficult to separate in the field and most people identify them by locality and type of food plants.

The common chinch bug is normally found from South Dakota across to Virginia and south to a line running from mid-Texas across to mid-Georgia. The hairy chinch bug cohabits some of the northern range of the common chinch bug but also extends throughout the northeastern states and into southern Canada.

The hairy chinch bug prefers turfgrass species such as fine fescues, perennial ryegrasses, Kentucky bluegrass, bentgrass and zoysiagrass. The common chinch bug prefers grain crops such as sorghum, corn and wheat but will attack turfgrasses such as Bermudagrass, fescues, Kentucky bluegrass, perennial ryegrass, zoysiagrass and crabgrass.

Shortwinged Adult	Bigeyed Bug Adult

Types of Damage

Chinch bug damage is usually first detected when irregular patches of turf begin to turn yellow then straw colored. The straw colored areas may be completely dead. These patches continue to become larger in spite of watering.

Apparently, feeding by chinch bugs blocks the water and food conducting vessels of grass stems. By blocking the water, the leaves wither as in drought and the manufactured food doesn't get to the roots. The result is plant death. Damage generally occurs during hot, dry weather from June into September.

Description of Stages

These pests are true bugs and have a gradual life cycle with egg, nymphal and adult stages. All the species of Blissus are very similar in form and an expert is needed to separate species and subspecies.

Eggs

The eggs are elongate, bean-shaped, approximately 0.84 mm long by 0.25 mm wide, and are roundly-pointed at one end and blunt at the other. The blunt end has several small tubercles visible through a dissecting microscope. The eggs are first white and change to bright orange just before hatching.

Nymphs

There are five nymphal instars which change considerably in color and markings. The first instar has a bright orange abdomen with a cream colored stripe across it, a brown head and thorax and is about 0.9 mm long. The second through fourth instars continue to have this same general color pattern except that the orange color on the abdomen gradually changes to a purple-gray with two black spots. The fourth instar increases to more than 2 mm long. The fifth instar is very different because the wing pads are easily visible and the general color is now black. The abdomen is blue-black with some darker black spots and the total body length is about 3 mm.

Adults

The adults are approximately 3.5 mm long and 0.75 mm wide. The males are usually slightly smaller than the females. The head, pronotum and abdomen are gray-black in color and covered with fine hairs. The wings are white with a black spot (the corium) located in the middle of the front-wing edge. The legs often have a dark burnt orange tint. Individuals in a population, or in some cases, most of a local population may have short, called brachypterous, wings which reach only half-way down the abdomen.

Life Cycles and Habits

The hairy chinch bug adults overwinter in the thatch and bases of grass stems in the turf. However, the common chinch bug prefers to move to tall bunch-grasses in open fields to find overwintering sites. These individuals then migrate in search of grain crops in the spring but may establish in turf instead. The adults of both species become active when the daytime temperatures reach 70 degrees F. The females feed for a short period of time and mate when males are encountered. Eventually the females begin to lay eggs by inserting them into the folds of grass blades or into the thatch. This usually occurs from mid-April into June, from New York to Illinois. A single female may lay up to 200 eggs over 60-80 days. The eggs take about 20-30 days to hatch at temperatures below 70 degrees F but can hatch in as little as a week when above 80 degrees F. The young nymphs begin to feed by inserting their mouthparts in grass stems, usually while under a leaf sheath. The nymphs grow slowly at the beginning of the season because of cool temperatures but speed their development by July. Usually the first generation matures by mid-July. At this time considerable numbers of adults and larger nymphs can be seen walking about on sidewalks or crawling up the sides of light colored buildings. If a good, hot, dry spring is available, turf injury by the first generation can be evident by June. Damage may be visible from late-June through August when the spring generation mature nymphs and adults are feeding and the second generation of nymphs are becoming active. During the hot summer months, the new females lay eggs rapidly and their young may mature by the end of August into September. The second generation adults may lay a few eggs for a partial third generation if the season has been long. However, most of these late nymphs do not mature before winter temperatures drop. When cool temperatures arrive, the mature chinch bugs seek out protected areas to spend the winter.

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Cutworms

The larvae or caterpillars of some moths are called cutworms (Agrotis, Amathes, Peridroma, Prodenia spp.) because of the manner in which they cut down young plants as they feed. The adults are night-flying moths which feed on nectar, if at all, and do no damage.

Damage:

There are a great many species of cutworms. While they all feed on plants by chewing, they vary as to damage done and host plants preferred. Generally they destroy more of the plant than they eat. Their numbers vary greatly from year to year and, when numerous, may destroy as much as 75% of a crop. Cutworms injure plants in four major ways:

- Solitary surface cutworms cut off young plants at or slightly above or below the soil line, sometimes dropping the severed plants into their burrows. Because most of the plant is not eaten, these cutworms do great damage, attacking and felling new plants nightly. The black, bronzed, clay-backed and dingy cutworms are in this group.

 

Black cutworm and damaged stalk
(Clemson University Extension)

• Climbing species, usually the variegated and spotted cutworms, climb the stem of trees, shrubs, vines, and crops and eat the leaves, buds and fruit.
• Subterranean species, particularly the pale western and glassy cutworms, remain in the soil and feed upon roots and underground parts.
• Army cutworms occur in great numbers, consuming the tops of plants and then "marching" on to other fields.

Description:

The many species of cutworms can be quite distinct. Many are stout, smooth, soft-bodied, plump caterpillars. These vary from brown or tan to pink, green or gray and black. Some are all one color, others spotted or striped. Some larvae are dull, others appear glassy. The adults are generally very robust brown or black moths showing various splotches, blotches or stripes in shades of gray, brown, black or white. 

Life Cycle:

Most cutworms pass the winter as partially grown larvae. Thus they are already large, voracious feeders when transplants and seedlings are set out in the fields. A few species pass the winter as pupae or hibernating moths. Overwintering cutworms may live under trash or bark, in clumps of grass or in earthen cells in the soil. These cutworms become active and begin feeding as the weather warms in spring, remaining hidden under debris or in the soil and feeding at night. Many species continue to feed well through June, then pupate in the soil to emerge later as moths. Normally there is only one generation per year. The moths crawl from their brown pupal cases in the soil and climb up through the soil, following the tunnel made by the burrowing larva. If this tunnel is blocked, the fragile moth cannot escape the soil. Cutworm abundance and development is greatly affected by weather, especially rainfall. The moths mate and lay eggs in late summer, beginning the next generation. The moths often seek out grassy or weedy areas to lay their eggs, which are usually deposited on plant stems or in the soil. One female may lay hundreds of eggs. The hatching larvae feed until cold weather and then hide for the winter in a sheltered, dry place.

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Deer Tick: 

 

The most important pest to control in your backyard!

More about Lyme  Disease

Facts To Know About Deer Ticks

The Deer Tick, Ixodes dammini, is the vector for Lyme disease in the northeastern United States, primarily because this tick has been most extensively studied. There is ongoing debate whether I. dammini is conspecific with I. scapularis, the member of the I. ricinus complex present in the southeastern United States. What is clear is that the northern tick population poses a much greater threat of transmitting Lyme disease. Possible explanations for the apparent increase in the population of I. dammini and the expansion of its geographic range are reviewed, as is the impact of changing patterns of land use in the United States over the past century, which have created environments ideally suited for ticks and deer (the preferred host for adult I. dammini ticks) and which bring humans into close proximity to both.

An important concept (albeit relatively simple) is that the total population of ticks in a region is a result of the balance among fecundity (the number of offspring produced per female), mortality, and migration. The maximal number of offspring per adult female tick is estimated to be approximately 3000.

In view of the tick's two-year life cycle, assuming equal sex distribution of progeny, a single female could produce up to 4.5 million offspring in just two years. This astounding fact suggests a tremendous excess tick mortality during development. However, little is known about how to increase this mortality so that the risk of Lyme disease can be meaningfully reduced. It also suggests that approaches focused on adult female ticks might be the more fruitful than approaches focused on ticks in immature stages.

Possible techniques of environmental management to reduce the risk of the disorder will require IPM. Options discussed include measures for personal protection as well as environmental measures, including "habitat modification" (e.g., burning underbrush), "host exclusion" (e.g., deer fencing), and both "off-host" methods (e.g., insecticides) and"on-host" options to increase tick mortality. Several possibilities of particular scientific interest are distributing insecticide-impregnated cotton balls in the environment where mice (important hosts forimmature I. dammini ticks) may use them in nesting material; developing vaccines against tick saliva to promote rejection of the tick during feeding, thereby preventing engorgement, particularly of adults feeding on deer, and thus interrupting the tick's life cycle before mating; and developing mixtures of pheromones with acaricides. Pheromones are chemical compounds produced by ticks as chemical signals to facilitate communication. Some pheromones are attractants (for example, sex pheromones); they could be tagged with tick insecticide (acaricide), thus increasing its power.

It is highly likely that the successful control of Lyme disease will require an integrated management approach that will include personal-protection measures, improved diagnostic and therapeutic approaches, and environmental interventions at many levels.

In this era of increased consciousness of the costs of public health as well as those of individual health care, interventions must be chosen with attention to what is most likely to reduce the risk of Lyme disease.

Most ticks start out in leaf litter or soil on the ground. When they are ready to feed, which most do three times in their life, they might crawl on top of a piece of grass and wait for an unsuspecting host.

Daniel W. Rahn, M.D.
Medical College of Georgia
Augusta, GA 30907
http://www.mcg.edu

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How weather affects grasshoppers
Temperature Effects High temperatures in summer - fall     Early maturity of grasshoppers     Long egg laying period Warm spring     Early hatch, followed by:     <70o -->No feeding, high mortality     Warm and dry --> Good start for      hoppers Winter temperatures have little affect	Rainfall Effects Cloudy, wet weather for 1+ weeks     Promotes fungal pathogens     of grasshoppers     Prolonged wet period important Heavy rains during emergence     Kills young grasshoppers        embeds young hoppers in soil        physically wash them away Extreme drought     Poor egg hatch     Hoppers starve from lack of food     Low egg production by adults
Weather effects and their impact on grasshopper populations
Decrease when . . . Warm early spring       premature hatch       IF get a cold snap --> poor       development Hot period in early spring...        promotes hatching   ...following by cloudy, wet weather        favors the occurrence of disease Cool summer and early fall        delays the maturity of the        grasshoppers        shortens the time for egg laying	Increase when . . . Cool, wet weather in early spring        prevents premature hatch        insures adequate food supply Warm and dry in late spring       promotes uniform hatching time       good weather conditions for       feeding Hot summer with adequate rainfall       provides good food supply       low incidence of disease Late fall       long egg laying period