crocus and eastern redbud (Cercis canadensis) are blooming. They may be seen crawling on fairways or putting greens on warm, sunny afternoons in April and May, or they may be picked up in mowing baskets along with the clippings. Egg-laying continues into early June.

Eggs hatch in about one week, and the grubs feed on fine roots and organic matter. Individual grubs take about one month to mature. They then burrow down, pupate and emerge as adults in late June and July. These beetles produce a second brood of grubs that damages the turf in late summer and early fall. New adults emerge in September and October, mate and fly to overwintering sites.

Full-sized (third-instar) BTA grubs are only about ³Ž8 inch long, about the size of Lincoln's hair on a U.S. penny. They sometimes are mistaken for young grubs of Japanese beetles, masked chafers or other larger species. BTA grubs can be distinguished by a pair of pad-like bumps at the tip of the abdomen, just in front of the anal slit. These are fairly easy to discern with a 10* hand lens. The main blood vessel, which runs longitudinally down the back, typically appears almost black in contrast to the gray-white body.

Fairway-height turf will usually tolerate at least 30­50 BTA grubs per square foot unless further stressed by drought, compaction or disease. With higher densities or infestations in putting greens or collars, control may be warranted. Localized infestations can often be spot-treated. Less often, whole fairways will require treatment.

Preventive control may be justified on sites with recurring BTA problems. One strategy is to spray a short-residual insecticide to intercept the females when they return to the turf for egg-laying. Watch for increasing numbers of black beetles crawling on putting greens, or in mowing baskets, during April and May. Pyrethroids, for example, deltamethrin (DeltaGard), lambda-cyhalothrin (Scimitar), bifenthrin (Talstar) or cyfluthrin (Tempo), provide good adult control at very low rates. Chlorpyrifos (Dursban) or acephate (Orthene) can also be used. Use enough spray volume, or irrigate lightly following the application, to deposit residues in the upper thatch.

Certain flowering plants can help to time such applications because their blooming coincides with the onset of egg-laying activity. Spraying when Vanhoutte spirea, bridal wreath spirea or bridal veil spirea are in full bloom, covered with white flowers, will control the adults before they lay eggs. Full bloom of horse chestnut and first bloom of black locust also coincide with the treatment window. Springtime cutworm treatments with any of the aforementioned insecticides should simultaneously control BTA adults that are active on greens.

Insecticides that have a long residual effect in the soil offer another preventive option. Applying imidacloprid (Merit) or halofenozide (Mach 2) in late May or early June will control first-generation BTA grubs, with residues generally persisting long enough to control annual grubs (for example, Japanese beetle, masked chafer) that appear later in the summer. When deploying this multiple-targeting strategy,

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