Weed Identification Guide: These Weeds Are the Worst

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worst weeds

What are the worst weeds to have in your lawn? That is a difficult question to answer for the entire country, as certain weeds grow better in some areas than others. There are a few that seem to grow just about everywhere, so for now I’ll discuss them—and how to control them—in a brief weed identification guide. These are listed in no particular order, except being the ones I thought of first.

1. Wild Violet

wild violet weed identification

You either love them or hate them. It does have a pretty flower that can range in color from white to blue to purple. This weed prefers cool, moist shady areas, but will tolerate full sun. The difficulty in controlling this weed is its extensive root system. It has a deep taproot as well as the ability to produce above-ground roots called stolons and below-ground roots call rhizomes. Violets are extremely difficult to control and require multiple applications of broadleaf weed control products. The best time to control this plant is in the fall, after the first frost.

2. Ground Ivy

ground ivy weed identification

Ground Ivy is pretty easy to identify. It is a creeping winter perennial that can send its stolons snaking out through a lawn. This is where it gets some of its more common names such as Creeping Charlie or Creeping Jenny. It also likes moist, shady areas, but can grow in the full sun. Just like Wild Violets, it is very difficult to control, needs multiple applications, and is best controlled in the late fall.

3. Virginia Buttonweed

virginia buttonweed weed identification

Our weed identification guide continues with Virginia Buttonweed, which is probably the worst weed in the South and Southeast regions, but it can survive as far north as southern Pennsylvania, Ohio, Indiana, and Illinois. It is a prostrate-growing perennial weed that can form large patches in home lawns, choking out the desired grasses. It mainly reproduces by seeds, but a new plant can grow from plant segments that are left behind from mowing or hand pulling.

4. Canada Thistles

canada thistles weed identification

There are numerous thistle species that can be found in home lawns, such as Bull Thistle, Musk Thistle, and Sow Thistle. To help with identification, almost all thistles have sharp, pointy spines either on the leaf margins, edges, or covering the entire leaf surface. Of all the different species of thistles, the worst one (in my opinion) is the Canada Thistle. The main reason for my designation of “worst weed” is that this is a perennial plant that produces extensive rhizomes that can grow three feet or more in length and quickly take over any lawn or landscape area. You may be able to control this weed when it is growing in your lawn, but if there are plants growing in surrounding areas, the rhizomes will send out a new crop of plants to take the place of those that were controlled. Thirty-seven states have listed Canada Thistle as a noxious weed.

5. Crabgrass

crabgrass weed identification

There are at least 3 species of crabgrass that can be found in residential lawns: Hairy, Smooth, and Egyptian crabgrass. Crabgrass grows very flat to the ground and spreads out, choking the desired grasses. It is an annual grassy weed that is the bane of many homeowners. It may not be as important to identify which type of crabgrass you have; what is important is that there are pre-emergent products that you can apply to help prevent it from germinating, and there are even products that you can apply to kill it if it has germinated in a lawn. One crabgrass plant can produce thousands of seeds to leave behind for the following year’s crop.

6. Dandelion

dandelion weed identification

Dandelion gets its name from the shape of the flower; it resembles the face of a lion. The most hated part of this weed is the white puffball seed head that it produces after it has flowered. Actually, the flower itself is somewhat attractive, and once it has bloomed and produced seeds, it is somewhat inconspicuous in a home lawn – unless you have a lot of them. Dandelions are perennial plants and can germinate from the numerous seeds that are spread by the wind.

7. Clover

clover weed identification

This is a plant that you either love or hate. At one time, people actually used clover as a lawn “grass.” It can be considered an indicator of low soil fertility. It has the ability to produce its own nitrogen on nodes that grow on its roots. It is a perennial plant that reproduces by stolons and seed. The flower is favored by several species of bees. It is another one of those difficult to control weeds that requires multiple applications for complete control. There are literally hundreds of weeds that can grow in home lawns and I have just included 7 in this brief weed identification guide. The weeds that I listed can be found throughout the country with the exception of Virginia Buttonweed. The definition of a weed is “a plant growing out of place,” but you have to be the one that decides what “growing out of place” means to you. If you do find there are several plants growing out of place in your yard, and you want to get rid of them, contact your local Spring-Green for a free estimate.