use the highest labeled rate and treat as close as possible to BTA egg hatch (late May to early June at the latitude of southern Ohio). Earlier (April to early May) treatments will control first-generation BTA, but they may "run out of gas" before the annual grubs have hatched.

BTA grubs can also be controlled with insecticides that do not persist in the soil for as long (for example, trichlorfon [Dylox], bendiocarb [Turcam]) after egg hatch or when damage first appears. Follow with irrigation to move the residues into the soil. As with all curative treatments, the younger the grubs, the easier they are to control.

BTA grubs are susceptible to their own naturally occurring strain of milky disease, but the causal bacteria are not commercially available. Milky disease products presently on the market will not control BTA. Nematode-based insecticides have shown promise against BTA, but the ones marketed so far have been less reliable than conventional insecticides. Endophyte-infected grasses have not shown much resistance to white grubs, including BTA.

BTA belongs to the subfamily Aphodinae, a group of small beetles that in natural habitats feeds mostly in animal dung or decomposing organic matter. If BTA are predisposed to deposit their eggs in manure or compost, then it wouldn't be surprising to find them interested in odors emanating from organic fertilizers. Indeed, in a recent study, I found that certain types of fertilizers may attract BTA adults, resulting in higher grub populations in turf.

The two-year study was conducted on a northern Kentucky golf course. Fairways and greens are perennial ryegrass and creeping bentgrass, respectively. Fairways had a background density ranging from fewer than 10 to 100 BTA grubs per square foot. Some of the greens that had been treated with organic fertilizers had sustained severe BTA damage in the summer preceding

my research. For practical reasons, my tests were done on the fairways.

Three types of slow-release, granulated organic fertilizers were evaluated: Milorganite (6-2-0), which contains organic solids from activated sewage sludge; Nature Safe (8-3-5), which contains meat-processing waste (feather, meat, bone and blood meals); and Sustane (5-2-4), made from aerobically composted turkey litter. Granular urea (46-0-0) was included in the first year's test as a nitrogen standard. Because the granular urea caused some turf burn, in the second year we used a standard

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