CHARLESTON, W.Va. -- Weeds. Sometimes it's hard to figure out which plants are weeds and which ones are just offspring of something desirable. And then there's the problem of how to get rid of them.
Let's start with the identification.
There are hundreds of websites aimed at weed identification. After visiting 20 or more of these sites, I found that many lead to the same ID tool from the Weed Research & Information Center. I found this one hard to use and frustrating.
The University of Tennessee has a good weed identifier, as does Michigan State's extension service (www.msuturfweeds.com).
The best site, with the best photographs, is run by the University of California Agriculture & Natural Resources Department, www.ipm.ucdavis.edu/PMG/weeds_intro.html. This website, a product of the statewide integrated pest management program, is easy to navigate, and has great photos to help identify all of the weeds in your garden.
The biggest question, after identification, is control. I'm sorry to say there are only a couple of options.
The best option is prevention. A healthy garden and lawn, regularly tended, will keep weeds at bay. Using a pre-emergent weed killer, such as Preen, helps. Pulling weeds before they germinate is critical. But for those of us who have let some of our beds "go to seed," so to speak, the alternatives are usually pulling by hand or using herbicides.
I can't use chemicals in my beds, because the weeds are often closely mixed with the "real" plants. So I'm always pulling, pulling, pulling. I've included chemical control suggestions for those of you who use herbicides.
Here are the ones I'm battling in my yard.
Ground ivy (Glechoma hederacea), also known as creeping Charlie, is an aggressive, low-growing, perennial invader of lawns, vegetable gardens and flower beds. It thrives in moist, shady areas as well as sunny locations. The scalloped leaves are round or kidney-shaped and are attached by petioles to square stems.
Ground ivy spreads via creeping stems that propagate new plants. Ground ivy will root at each joint whenever it touches the soil, thus making it difficult to pull. Ground ivy spreads by seed and stolons. It can root at each leaf node, so it establishes itself very quickly. Another problem with pulling is the difficulty in getting the whole plant. Rooted nodes left behind will grow and spread.
Ground ivy is hard to control because many commercial broadleaf lawn weed killers have little or no effect on it. Pre-emergence herbicides do not control it; accordingly, we are left with post-emergence controls. Most common broad-leaved weed controls are ineffective by themselves.
The most effective control comes with the use of combination herbicides that contain the product dicamba, applied from mid-September to early November. The next-best time to control ground ivy is when it is just beginning to flower, at the end of April. Two herbicide applications, spaced about 28 days apart are usually needed.
Broadleaf plantain is common in lawns. It is a cool-season perennial weed found practically in any habitat. The leaves are arranged in a rosette and have prominent veins. Depending on the species, leaves and stems may range from purplish to dark green in color and may be smooth or densely covered with short hairs. Seed heads are rattail-like and 5 to 10 inches long.
Both buckhorn, or narrow-leaved plantain (Plantago lanceolata), and broadleaf plantain (Plantago major) are perennial weeds that reproduce by seeds. Both produce a rosette or cluster of leaves at ground level and have fibrous root systems.
Both plantains produce erect flower stalks from June to September. Seed germinates in late spring through midsummer and sporadically in early fall.
Hand pulling is a simple, practical approach for small areas. Post-emergence herbicides are available depending on the kind of turfgrass in your lawn. Optimum timing of post-emergence herbicides is mid-autumn.