Weeds

Weeds are really just one type of plant that we have decided shouldn’t be growing in one particular place. Wild orchids growing in Hawaii are considered weeds. It’s just your point of view as to what makes a weed a weed. Some weed-type plants are invasive and fast growing. Their growth habit overtakes our cultivated turf plant, depriving them of food and water.

In the lawn, the most common weeds are just a nuisance. What they’re also telling us is that the lawn isn’t as healthy as it should be. Turf grasses today are so adept at growing into thick masses, that if maintained properly, weeds are not a problem. It’s when the lawn isn’t as healthy as it could be that we see weeds becoming a problem.

3 basic types of lawn weeds

There are 3 basic types of weed in lawns:

1. grassy type weeds
2. grass-like weeds
3. broadleaf weeds

Some common lawn weeds are annuals. Sprouting from seeds, they develop, blossom and form new seeds, and then die in the fall, repeating the process each year. Crab grass is one such weed. The ideal control prevents them from developing in the first place.

Applying a pre-emergent control in the spring and fall does this. Of course there is no 100% guarantee that additional seeds won’t be carried in by winds, birds, or any number of other methods.

To treat for weeds in your lawn, you have to understand the type of weed you have. Since different type weed requires different types of treatment.

Grassy Type Weeds

Maintaining a dense, vigorous turf is the best weed control. Herbicide applications are mandated to reduce weed populations to tolerable levels. When annual grassy weeds such as crabgrass, goose grass, barnyard grass, fall panicum, or yellow foxtail become a problem preventive pre-emergence herbicides are often used for control.

For annual grass control, apply pre-emergence herbicides prior to germination. The soil temperatures necessary for weed seed germination vary by species. For example, crabgrass germinates in soil temperatures that are greater than 55 to 60 degrees Fahrenheit for 7 to 10 days, and continues to germinate in soil temperatures to 95 degrees Fahrenheit. Goosegrass begins germinating when soil temperatures are above 65 degrees Fahrenheit for several weeks, and yellow foxtail germinates at soil temperature of 68 to 92 degrees Fahrenheit. Barnyard grass germinates at soil temperatures between 72 and 90 degrees Fahrenheit. The optimum soil temperature for fall panicum germination is 80 degrees Fahrenheit.

Grass-like Weeds

Grass-like weeds at first glance look like a grass, but are relatively easy to distinguish from grasses. Upon close inspection, the stems are triangular in shape. Common grass-like weeds include yellow nut sedge, wild garlic/onion, and star of Bethlehem.

Broadleaf Weeds

Broadleaf weed are generally the easiest to identify of all weeds. They have leaves that are broad, and are generally produced in pairs or multiples have wide, flat leaves situated on a stem. Broadleaf weeds are distinctive from and are botanically not closely related to grasses and sedges. Broadleaf leaves may be simple (having one leaflet, like a dandelion) or compound (having more than one leaflet like clover). Veins within the leaf give a netted appearance in most cases. Even with proper management, however, the best-cared-for lawns can still be invaded by troublesome broadleaf weeds. These may require the careful and selective use of broad leaf weed control herbicides.