BLUEGRASS BILLBUG (Sphenophorus parvulus)

Prepared by: Dr. M. Keith Kennedy Extension Specialist Department of Entomology Michigan State University

The bluegrass billbug is a common turf pest which occasionally causes extensive damage to home lawns. These beetles are named because of their long snout or "bill" which ends in a set of small mandibles or jaws. They are usually seen in the spring (April-early May) or late fall (September- October) wandering about on sidewalks, drive ways, or patio's.

The presence of billbugs in the lawn is generally not detected until the first signs of damage appear. Often this damage is attributed to other causes. The following information should assist you in becoming more familiar with this turf pest.

Sphenophorus parvulus

Hpsts Kentucky Bluegrass (Poa pratensis)

Characteristic Damage spotty dead patches of turf scattered throughout the laWn in July and August.

How to Recognize Adults - dull grey (lots of scales) to black or brown beetles, h+h" long, with a snout or bill. Adults have wings but seldqft fly* Larvae - white, leggless, 5/8" long, humpbacked grubs with a yellow to brown head capsule.

Adult Larva

l/l^icich 1/If. inch

Damaging Stages adults feed on grass blades or stems but the major damage is caused by larvae feeding in the stem and roots.

Life Cycle Billbugs overwinter as adults and become active as temperatures begin to warm in April. Eggs are first laid in grass stems in early May but most eggs are deposited in early June. (See Fig- 1) Eggs hatch in two weeks and the larvae tunnel down through the grass stem into the crown and eventually settle the roots. Mature larvae may feed across the crown severing the roots. Larvae may be present the remainder of the summer but peak densities occur in early-mid July. Old adults (overwintered) may persist throughout the season but the new summer adults begin to emerge in late August and September. They generally seek out sheltered areas to spend the winter and can be observed walking around driveways, patio's, near ground cover, etc at this time. There is only one generation/year.

Apply Control Life cycle of Bluegrass billbug. Arrow indicates best time to apply controls.

How to Diagnose Billbug Damage Use the following set of characters to properly ;diagnose billbug injury. 1) Grass in dead areas of lawn will pull up easily and the sifcems S ifill be hollow. 2) A white,legless, humpbacked larva may be present in or und&r the crown or in the soil up to 1 inch deep. 3) Brown sawdust-iike frass will be present in the root zone. 4) Adults may be present in adjacent grass. , «,

Economic Threshold - Damage to turf generally occurs, when larval densities are 10/sq. ft. or higher. 1

Control Strategies Adults: Sprays should be applied in late April or early May to control overwintering adults before they begin to lay eggs. Larvae: Once larvae have tunneled into the grass stem, control is very difficult. Moreover, poor results are often obtained because the insecticide was not watered into the root zone sufficiently to contact the larvae. Proper dosage, application and irrigation will provide some larval control but efforts should be primarily directed at the adults in May.

Chemicals Adults and larvae: Diazinon 4 lbs/gal EC at 4 oz/1000 sq. ft. or qts/ acre. Baygon and Sevin are also registered but may not be as effective. BLACK TURFGRASS ATAENIUS (Ataenius spretulus) Prepared by: Dr. M. Keith Kennedy Department of Entomology Michigan State University

Ataeniu9 spretulus is a small black beetle which belongs to the family of beetles known as scarabs (Scarabaeidae). These beetles are saprophagous, i.e. they normally feed in dung or humus rich in decaying organic matter.

Although A. spretulus was first described attacking turf in Minnesota in 1932, it has only recently become a problem. The larval or "grub" stage of this beetle severely damaged fairways of annual blue grass (Poa annua) on a golf course near Cincinnati, Ohio in 1973. Since then, the beetle has been recognized as a problem on golf courses in 20 states ranging from Colorado to Connecticut and from Ontario Canada as far south as Kentucky.

In 1978, it caused considerable damage to annual blue grass fairways in both the Detroit and Saginaw areas of Michigan. The following information will provide you with a brief description of the beetle's life cycle and recommended controls for Michigan turf managers.

Ataenius spretulus

Favored Hosts Poa annua bentgrass perennial bluegrass Characteristic Damage localized dry spots or wilting turf occurring in mid June despite regular irrigation. How to Recognize Adults - shiny black beetle 5 mm in length; newly emerged adults may be reddish to chestnut brown Larvae - white C~shaped grubs 5 mm long when mature with legs and a tan head capsule. Three larval instars occur. Rostral pattern is scattered.

Life cycle

Adult beetles overwinter beneath leaf litter as well as the upper two Inches of loose, well drained soil at the edge of wooded areas, river banks, etc. Seems to prefer pine litter.

Overwintering adults emerge in late March (at time of 1st crocus bloom) and return to golf fairways through April and May.

Egg laying occurs in early May about the time Van Houtte spirea and black locust are in full bloom, and tapers off in early June. Life Cycle (cont.)

Eggs are laid in the thatch or in upper 1/4 inch of the soil immediately beneath the thatch.

1st generation larvae are present from June - mid July (see Fig. 1).

Larvae burrow 1-3 inches into the soil to pupate in late July - early August.

Newly emerged adults lay more eggs in August (when rose of Sharon is in bloom).

2nd generation larvae mature in late August when Canada goldenrod is in bloom.

2nd generation adult3 leave fairways to seek overwintering sites in late September to early October.

Apr May June July Aug Sept Oct

Figure 1. Life cycle of A. spretulus showing adult and larval activity. Economic Threshold - Damage to turf generally occurs when grub densities are greater than 50-75/sq. ft. but may occur at densities of only 30/sq. ft. Severe damage occurs when there are 300-500 grubs/sq. ft.

How to check for grubst Remove a sq. ft. of turf and soil 2-4 inches deep in several locations. Ten to 20 samples over the golf course may need to be taken, a greencup cutter is also good.

Control Strategies

Adult control: A single, but appropriately timed spray to control overwintered adults has shown excellant results in preventing the buildup and damage of grubs later in the summer. The spray should applied after all overwintered beetles have emerged but before oviposition begins. This would be mid to late May in Michigan or just before VariHoutte Spirea, black locust, cottdnwood, Hawthorne or Horsechestnut reaches full bloom. A second application may be made 10-12 days later if deemed necessary.

Larval control: Good control of larvae (grubs) has been achieved with hydraulic sprays whenever larval populations become excessive Apply controls anytime larvae are found, but best results villi be obtained if the application is made before the 1st generation ' larvae reach maturity in late June to early July. Second generation larvae can be controlled in mid to late August. It is not necessary to treat the entire course since spot spraying of infested areas vill give good results.

Chemicals

For Adults: Diazinon 4 lbs/gal EC at 6 lbs Al/acre has given the best results thus far. ,

For Larvae: Diazinon A lbs/gal EC, Proxol 80 SP, or Proturf (Ethoprop) 5ZG have given adequate control, the latter being the least effective. CHINCH BUGS (Blissus spp.)

Prepared by: Dr. M. Keith Kennedy Extension Specialist Department of Entomology Michigan State University

The hairy chinch bug (B. leucopterus hirtus) and the common chinch bug (]$. leucopterus leucopterus) are the most frequently observed species in our area. Chinch bugs can be serious problems in lawns when conditions are warm and dry. Their damage is most frequently observed in late summer or early fall and is often attributed to some other agent. The-information below should help in diagnosing chinch bug problems.

Blissus spp. Hosts Bentgrass (most problems occur on this grass) Bluegrass Fescue

Damage Symptoms presence of irregularly shaped yellow patches tohich turn Brown and die. Clover and other non-grass weeds may survive in these areas.

How to Recognize Adults - small black bugs, 1/5" long with white wings and reddish legs. Nymphs - smaller than adults, wingless, brick red in color with a transverse white band on the back.

A. First stage or red nymph B. Second-stage nymph C. Winged adult

Damaging Stages both nymphs and adults damage grass but the most serious damage is done by the nymphs. Life Cycle

Adults overwinter in protected areas near lawns. They emerge in the late spring and early summer, when temperatures reach the 70's, mate and lay eggs in leaf sheaths. Each female lays an average of 200 eggs near the crown during the 3 to A weeks it is alive. Plant damage results not only from withdrawal of sap but chinch bug saliva contains . substances toxic to the plant and the puncture wounds often block plant conducting vessels. Nymphs require approximately 4 to 6 weeks to develop to the adult stage. First generation nymphs occur in late June to July and second generation nymphs are present in mid-August.

Weather and Chinch Bug Injury

A warm dry spring followed by below average rainfall in the early summet favors the buildup of chinch bug populations. Conversely a cold wet spring will drastically slow population growth and heavy rainfall in June and early July during egg hatch will reduce nymph survival. Much of this mortality is due to a fungus that attacks the bugs during cool, wet conditions. The fungus is ineffective during hot dry periods whem chinch bug buildup occurs.

How to Diagnose Chinch Bug Damage

1) Closely examine the green borders of the dead or dying turf areas for the presence of nymphs and adults. Remember, these bugs generally move outwards from the center of the initial infestation and feed on living grass.

2) A small area of lawn can be flooded to the puddling point to (float bugs to the surface or a coffee can without a bottom can be pushed into the turf and filled with water. Chinch bugs present will float to the surface in 5-10 minutes. This technique should be repeated 5-6 times in a lawn in case of uneven bug distributions.

Control Cultural. Since chinch bugs are usually not a problem in well irrigated turf, diligent watering of turf during hot d^y weather will help reduce this potential pest. Also reducing the amount of nitrogen fertilization has been shown to be effective in limiting chinch bug injury.

Chemical. Two applications may be needed to prevent damage in lawns where the bug has been a problem. Treat in early to mid June and again in early to mid August. Otherwise treat when bugs are observed. Diazinon, Dursban, Sevin, and Ethoprop are just a few of the materials that can be used. See MSU Extension Bulletin E-944 for more details on chemicals to use and rates.