Controlling Weed Grasses in Home Lawns

Weed Grasses, such as crabgrass, annual bluegrass, johnsongrass, velvet grass, and many other varieties are a significant problem in lawns in the Portland-metro area. Control or suppression of these undesirable grasses is possible with the timely application of the appropriate herbicide.

  There are two general types of weed grasses. They are either an annual variety or a perennial variety. An annual must sprout from seed each year. It sprouts, grows, produces seeds, and then dies at the end of the growing season. Perennial weed grasses sprout from seed initially, but will grow, live from year to year, producing seed each season that they are alive. This type of grass can be treated with a non-selective herbicide like Killzall, or be physically removed by hand with a shovel or another type of tool, to get rid of it. Once the perennial weed grass is removed, the area it was in will need to be reseeded.

  Annual weed grasses can be controlled with the application of pre-emergent herbicides. These products are applied to lawns before the weed seed begins to sprout. An early application, ideally in February or March, is necessary for good control. Pre-emergents  kill the seed as it germinates, preventing the weed grass from ever getting established in the existing lawn.

  Burns Feed Store carries several products with pre-emergents that are labeled for use in home lawns. They are:

  • Hi-Yield Turf, Ornamental, Weed and Grass Stopper, 10 lb. This bag will cover up to 5000 sq. ft. of lawn area. An advantage to using this product is that it can bee applied to both lawns AND flower bed areas. It controls a wide variety of weeds and weed grasses.
  • Bonide Weed Beater Complete, 10 lb. This product will cover up to 5000 sq. ft. of lawn. It is both a pre- and post-emergent herbicide. It prevents weed and weed grass seed from germinating AND can also kill a wide variety of existing broadleaf weeds in the lawn.
  • Bonide Crabgrass Preventer with slow-release nitrogen for lawn, 16 lb. Covers up to 5000 sq. ft. of lawn. This product contains a spring fertilizer in addition to the pre-emergent that controls crabgrass, weeds, and many other weed grasses.
  • Ferti-Lome Crabgrass Preventer plus Lawn Food 20 lb. This item has the same weed preventer as the Hi-Yield product mentioned above with the added benefit of a spring fertilizer being applied along with the pre-emergent.



Each of the products above should have a follow up application applied 8 weeks after the first treatment. A fall application is necessary in late September or early October to prevent any winter germination of weed grass. Come by Burns Feed Store and pick up a bag or two of any one of the products mentioned, if weed grasses are a persistent problem in your lawn. We can help you choose the right product for your lawn and get those problem weed grasses stopped!