Research Articles continued
Efficacy of selected soil insecticides against white grubs in turf Virginia Tech Researchers: Rod Youngman, Ph.D., Professor; Curt Laub, Research Associate; and Shaohii Wu, Dept. of Entomology Research Sponsors: Virginia Turfgrass Foundation and Virginia Agriculture Council
In
Table 1. Treatment list for 2011 VAC/VTF turfgrass soil insecticide efficacy trials at Tazewell Country Club, Virginia. Trt. No.
Application Timing
Treatment/ Formulation
Application Rate (amt. product/acre)
1
April 20
Acelepryn 1.67SC
8.0 fl. oz.
2
April 20
DPX-HGW86 20SC
8.0 fl. oz.
3
April 20
Allectus GCSC
4.5 pt.
4
April 20
Merit 75WP
6.4 oz.
5
July 19
Zylam 20SG
32.0 oz.
6
July 19
Acelepryn 1.67SC
8.0 fl. oz.
7
July 19
DPX-HGW86 20SC
8.0 fl. oz.
8
July 19
Merit 75WP
6.4 oz.
9
—
Untreated check
—
Table 2. Site 1 white grub counts for 2011 VAC/VTF turfgrass soil insecticide efficacy trials at Tazewell Country Club.
2011, we conducted white grub efficacy trials at the Tazewell Country Club (in Tazewell County, Virginia) to evaluate the efficacy of various soil insecticides against white grubs on golf course turf. Both sites contained a mixture of 80% fescue and 20% bluegrass.
Our research
Table 1 lists the treatments and rates that were included in this study. Application timings were either early (April 20) or late (July 19). Liquid insecticide treatments were applied as foliar sprays, using a CO2 backpack sprayer equipped with 4, 8008VS stainless steel spray tips and calibrated to deliver 80 gpa at 40 psi. Table 3. Site 2 white grub counts; 2011 VAC/VTF turfgrass soil insecticide efficacy trials at Tazewell Country Club, Virginia.
Treatment/ Formulation/ Timing
White grubs per sq. ft. (± SEM)
Treatment/ Formulation/ Timing
White grubs per sq. ft. (± SEM)
Untreated check
24.13 (3.48) a
Untreated check
19.13 (2.45) a
DPX-HGW86 20SC April
23.25 (5.22) a
DPX-HGW86 20SC April
14.25 (3.82) ab
Merit 75WP April
22.00 (4.26) a
Allectus GCSC April
11.50 (2.90) ab
Zylam 20SG July
19.00 (3.42) ab
Merit 75WP April
8.25 (2.46) ab
Allectus GCSC April
9.00 (1.63) b
Zylam 20SG July
5.50 (2.1) bc
Acelepryn 1.67SC July
2.00 (1.08) c
Acelepryn 1.67SC July
0.25 (0.25) c
DPX-HGW86 20SC July
0.75 (0.48) c
DPX-HGW86 20SC July
0.25 (0.25) c
Acelepryn 1.67SC April
0.00 (0.00) c
Merit 75WP July
0.25 (0.25) c
Merit 75WP July
0.00 (0.00) c
Acelepryn 1.67SC April
0.00 (0.00) c
Means within a column by site followed by the same letter are not significantly different (P > 0.05; LSD). 28 | Virginia Turfgrass Journal May/June 2012 www.vaturf.org