(G50)
MIXED TURF: Poa annua L. and Agrostis palustris L.
EFFICACY OF E2Y45 COMPARED TO TALSTAR AGAINST ANNUAL BLUEGRASS WEEVIL, 2005
Stanley R. Swier
University of New Hampshire
254 Spaulding Hall
Durham, NH 03824-3544
Phone: (603) 862-1733
Fax: (603) 862-1713
E-mail: [email protected]
Alan Rollins
Annual bluegrass weevil (ABW): Listronotus maculicollis Dietz
This trial was conducted on a fairway at Eastman Golf Links, Grantham, NH. Each treatment was replicated four
times, in 49-ft2 plots, using a RCB design. Six rates of E2Y45 1.67SC and one rate of Talstar F were applied to the
plots on 18 May. The applications were made within a wk after peak Forsythia bloom, and adults were migrating to
the fairways from their over-wintering sites. The grass was cut at 0.5 inch 24 h prior to applications, and every other
day thereafter, or on an as needed basis. None of the treatments were watered in. There was one-tenth of an inch of
precipitation 24 hrs prior to applications, and no precipitation within 24 h after applications. All treatments were
aqueous solutions, applied using a 7-ft boom on a bicycle-type sprayer. The boom was equipped with four 8005 flatpattern spray nozzles, fitted with 50-mesh screens. The materials were delivered with CO2 pressure at 40 psi; the vol
of water and insecticide mix was 2 gal/1000 ft2. The soil conditions at time of treatment were as follows: soil
texture, sandy loam; sand, 71%; silt, 15%; clay, 14%; organic matter, 10.1%; moisture, 18.8%, pH, 6.5; surface
temp, 67.1ºF; at 1-inch depth, 59.7ºF. Weather conditions were as follows: sky, overcast; wind, less than 5 mph; air
temp, 60.1ºF. The plots were rated for live ABW larvae and pupae on 7 Jul by removing four 4-inch cup-cutter
plugs, 2 inches deep, and tearing apart the plugs to reveal ABW. Data were subjected to ANOVA and means were
separated using DMRT (P ≤ 0.05).
All treatments had fewer grubs than the untreated check. DPX E2Y45 1.67SC performed as well as the standard
Talstar F at the rates of 0.2 lb to 0.4 lb, providing excellent control. No phytotoxicity was observed.
Treatment/
Treatment/formulation
DPX E2Y45 1.67SC
DPX E2Y45 1.67SC
DPX E2Y45 1.67SC
DPX E2Y45 1.67SC
DPX E2Y45 1.67SC
DPX E2Y45 1.67SC
Talstar 0.67F
Untreated check
Rate
lb(AI)/acre
0.1
0.2
0.25
0.3
0.35
0.4
0.1
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Total no.
a
ABW immatures
64
10
14
12
4
5
11
113
Mean no.
a
ABW immatures
16.00b
2.50a
3.50a
3.00a
1.00a
1.25a
2.75a
28.25c
Means followed by the same letter are not significantly different (DMRT, P > 0.05).
Figures represent ABW larvae and pupae in four plots per treatment.
a
Percent
control
43.4
91.2
87.6
89.4
96.5
95.6
90.3
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