Drive 75 Turf Injury

[lawnwerks]

Mix Rate: 1oz Drive in 3 Gal spot sprayer w/ sticker
Coverage per 3 gal: about 3000-4000 sq ft
Temperature: b/t 78-86 degrees

Did 3 test strips to see if drive is affecting turf below crabgrass applications.

Results: 4 days later-minimum tip browning
7 days later noticeable browning

Don't know why the product is doing this. Applications are even and are applied just enough to wet the crabgrass. If I try to cut back a little on the drive, get little to no effect.

Any suggestions would help. Thanks.

[RigglePLC]

Drive has worked OK for me. Mysterious. How much sticker? Most 3 gal sprayers only hold two gallons leaving one gal as an air chamber for compression of air. Was sprayer clean, ever used for Roundup? Was agitation adequate? Settled out? Turf under stress? Fine fescue? KBG? Rye?

Crabgrass is tougher this time of year--old and mature.

In my experiments at my micro research farm I sprayed drive at one teaspoon per quart with detergent as sticker, on new seedlings 15 days old (about 2 inches tall). No injury.

[grassman177]

i still get odd results, some dies fast and easy, some looks uneffected. same yard, same mix.

[lawnwerks]

Mostly KBG and Rye. Use the same rates of sticker recommended in my tank mix. I have a backback, so I am able to get 3 gals of liquid in there. Though I do mix my drive in with my trimec, but the label says that is acceptable.

Never used roundup-I never cross contaminate any tank or sprayer.

Thanks for the responses!