April 2017 - Page 10

Q and A NEWSPAPER COLUMNS

Controlling Grassy Sandbur

Q: My lawn is getting stickers already, help!

A: Grassy sandbur is the “sticker” plant that looks like a grass. It will often invade thin lawns, especially in dry years. Therefore, the best control for this weed is a thick, healthy lawn. However, if your lawn is thin this spring and grassy sandbur was a problem last year, use a preemergence herbicide before the sandbur comes up. However, not all preemergence herbicides are effective. The three products that can help minimize grassy sandbur are oryzalin, pendimethalin and prodiamine. Oryzalin is sold under the trade names of Surflan and Weed Impede. It can be used on all warm-season grasses as well as tall fescue. It should not be used on cool-season grasses other than tall fescue such as Kentucky bluegrass. Apply oryzalin about April 15 when redbud trees approach full bloom. Pendimethalin is sold commercially as Pendulum as well as several other names. On the homeowner side, it is sold as Scotts Halts. Pendimethalin is best applied as a split application with the first half applied about April 15 and the second about June 1. Alternatively, make the first application when redbud trees approach full bloom and the second six weeks later. Prodiamine is sold under the commer-cial name of Barricade. It is also the active ingredient in a number of homeowner products. It can be used on all of our common lawn grasses. Apply as is done for oryzalin, about April 15 or when redbud trees approach full bloom. Only one application is needed per year. None of the “weed preventers” will give complete control but each should help. Quinclorac (Drive) can provide some postemergence control especially if the sandbur is in the seedling stage. Quinclorac is also found in a number of combination products that control both broadleaf weeds and crabgrass such as one of the following: Ortho Weed-B-Gon Max + Crabgrass Control, Bayer All-in-One Lawn Weed and Crabgrass Killer, Monterey Crab-E-Rad Plus Fertilome, Weed Out with Q Trimec Crabgrass Plus Lawn Weed Killer, Bonide Weed Beater Plus Crabgrass & Broadleaf Weed Kille, or Spectracide Weed Stop for Lawns Plus Crabgrass Killer. Again, the best

control for grassy sandbur is a

healthy, thick lawn. Oryzalin is also

sold as a combination product with

benefin as Green Light Amaze. As

with oryzalin alone, it can be used

on all warm-season grasses as well

as tall fescue. It should not be used

on cool-season grasses other than

tall fescue such as Kentucky

bluegrass. Apply Amaze about April

15 when redbud trees approach full

bloom.