Preemergence Crabgrass Spp. Control with EH1579 and EH1580 Containing Vexis in Bermudagrass.

Field experiments were conducted in GA on large crabgrass and TN on smooth crabgrass. Treatments in GA consisted of EH1579 (penoxsulam + pyrimisulfan – inert carrier) [90 g ai ha^-1, 180 g ai ha^-1, and 90 g ai ha^-1 followed by (fb) 90 g ai ha^-1], EH1580 (penoxsulam + pyrimisulfan – fertility carrier) (90 g ai ha^-1, 180 g ai ha^-1, and 90 fb 90 g ai ha^-1), and indaziflam at 32.7 g ai ha^-1 (industry standard). Treatments were similar in TN, but industry standards consisted of prodiamine at 840 g ai ha^-1 and dithiopyr at 560 g ai ha^-1. EH1579 at 90 g ai ha^-1 resulted in 81% large crabgrass control 85 DAIT, while EH1579 at 180 g ai ha^-1 or 90 fb 90 g ai ha^-1 resulted in 73 to 80% smooth crabgrass control. EH1580 at 180 g ai ha^-1 or 90 fb 90 g ai ha^-1 resulted in 58 to 62% large crabgrass control and 89 to 93% smooth crabgrass control. EH1580 at 90 g ai ha^-1 only resulted in ≤ 63% crabgrass spp. control 85 DAIT. Crabgrass spp. control was ≤ 56% 112 DAIT in response to EH1579, regardless of rate, application frequency, or trial location. EH1580 at 180 g ai ha^-1 or 90 fb 90 g ai ha^-1 resulted in 68 to 69% large crabgrass control in GA, while a single application of EH1580 at 90 g ai ha^-1 only resulted in 41% control 112 DAIT. Smooth crabgrass control was 84% 112 DAIT in TN in response to EH1580 at 180 g ai ha^-1, while control dropped to 63 and 43% in response to EH1580 at 90 fb 90 g ai ha^-1 and 90 g ai ha^-1, respectively. Crabgrass spp. control was 96%, 91%, and 69% 112 DAIT in response to prodiamine, dithiopyr, and indaziflam, respectively.