Annual Bluegrass Weevil Research Articles

Seasonal Activity of Listronotus maculicollis (Coleoptera: Curculionidae) on Annual Bluegrass

Listronotus maculicollis (Dietz) damages annual bluegrass, Poa annua L., on golf courses, particularly in the metropolitan New York area. Biological studies conducted during 1976–78 on golf-course turf in Westchester County (N.Y.) or Fairfield County (Conn.) included weekly sampling each summer and approximately monthly sampling the remainder of the year. The insect generally overwinters in the adult stage, predominantly in white pine, Pinus strobus L., litter and other semiprotected areas on or near golf courses. Adults begin leaving their overwintering sites in mid- to late April and begin laying eggs in leaf sheaths in early May. Larvae begin emerging in mid-May, complete their development in mid-June, and pupate. Callow adults are first evident near the end of June. In 1976 and 1977, two complete generations occurred in most locations, and a partial third generation occurred in some locations. The cooler spring of 1978 resulted in only one complete and a partial second generation.

Chemical control of the "annual bluegrass weevil," Hyperodes sp. nr. anthracinus.

Laboratory bioassays and field-plot tests were conducted in 1968 and 1969 to find a chemical control for Hyperodes sp. nr. anthracinus (Dietz), a pest of annual bluegrass on golf courses. The most effective of 25 insecticides tested in laboratory bioassays were azinphosmethyl, Supracide® (S- ((2-methoxy-5-oxo-Δ2-1,3,4-thiadiazolin- 4-yl) methyl) O,O-dimethyl phosphorodithioate), fenthion, and Dursban® (O,O-diethyl O- (3,5,6-trichloro-2-pyridyl) phosphorothioate); the least effective were heptachlor and chlordane, In general, chlorinated hydrocarbons ranked near the bottom of the list. The systemic insecticides disulfoton, propoxur, fenthion, and Dasanit® (O,O-diethyl O-[p- (methylsulfinyl) phenyl] phosphorothioate) were applied on grass tennis courts May 3, 1968. None of the treatments satisfactorily controlled the annual bluegrass weevil, but disulfoton showed the most promise. Diazinon (14 G, 5 and 2 Ib active ingredient (AI) per acre), azinphosmethyl (22 EC, 2½ and I lb AI/acre), Supracide (14 G, 5 and 2 Ib AI/acre), disulfoton (10 G, 5 and 2 Ib AI/acre), Dursban (41 EC, 2½ and I Ib AI/acre) , and fenthion (5 G, 5 and 2 Ib AI/acre) were applied on grass tennis courts April 19 and May 19, 1969, and diazinon (14 G, 5 and 2 Ib AI/acre) was applied April 19 only. Nearly all the plots treated in April and May were conspicuously healthier than their surrounding controls, but the plots treated with diazinon in April only showed considerable damage. Dursban, 2½ lb AI/acre, gave the best control. The high rate of diazinon gave good control, while the low rate gave only fair control.