Scouting for spring weeds

April showers bring May flowers, but not everything that is growing and blooming right now is desirable. Our wet winter and spring have caused many weeds to start growing. It is time to start scouting for and controlling these early spring weeds.

Bur buttercup weed
Bur buttercup appears as a cute little flowering plant, but each flower will eventually form a sharp bur. Remove them now, before the burs are formed. Photo by Wendy Hanson Mazet, Cooperative Extension.”

Lawns are starting to green up, but not all that green is grass. Many lawns already have dandelions blooming. Dandelions are perennial plants. Removing the flowers and seed heads will help reduce the spread of dandelions in your lawn, but it won’t control the infestation. To control dandelions, the plants must be dug up, removing as much of the root as possible, or spot treated with a broadleaf selective herbicide.

Another lawn weed that is starting to bloom now is redstem filaree. The leaves of this plant are lacey and fern-like, forming a low-growing rosette. When the plant blooms, it forms small purplish-pink five-petal flowers. The seed it produces resemble a stork’s bill and can get caught in clothing and pet fur. This weed generally grows in wet areas with little other plant competition. To prevent further infestations, work on filling in the bare spots in your lawn and mow high (3 inches or higher). To control the redstem filaree you have now, remove them while they are still young and easy to pull, or apply a broadleaf-selective herbicide.

Bare areas in your landscape are open invitations for weed growth, especially if you had an infestation last year. Another early spring weed found in our area is bur buttercup. Bur buttercup only grows 2 to 5 inches tall. It seems so innocuous and cute with its short growth habit and little yellow five-petal flowers, but as the plant matures, each flower forms a ½-inch to ¾-inch long sharp bur. These burs are painful to humans, pets and wildlife. Now is the time to pull these little plants, before the nuisance burs form.

Bare areas are also showing flixweed, tumble mustard and kochia seedlings. Flixweed forms a lacey rosette as a seedling. Tumble mustard seedlings also form a rosette similar in appearance to dandelions. Both will quickly grow to 2 feet tall and are prolific seed producers. The seeds are long-lived in the soil. Kochia forms a small rosette of lance-shaped, fuzzy, gray-green leaves. It seems like such a pretty little plant that many people don’t pull it right away. In no time at all, it can grow into a highly branched, 1- to 6-foot tall Christmas tree-shaped plant that is difficult to pull. Remove these weed seedlings now, while they are young and easily controlled. The more mature the plant, the harder to pull. Additionally, if you opt for a chemical control, herbicides are much less effective on mature plants, and you will have to use more product to cover the large plants.

For more information on these and other common weeds, go to www.manageNVpests.info and click on the “common weed photos” link.

Melody Hefner is the Urban IPM and Pesticide Safety Education Program coordinator for University of Nevada Cooperative Extension. Have a gardening question? Ask a Master Gardener at 775-336-0246 or mastergardeners@unce.unr.edu.