Since pre-emergent season is just around the corner, what is a weed? The simple answer is anything you don’t want growing. Weeds fall into three categories: grasses like crabgrass, broad leaf-like henbit, and sedges. From here they are broken down into annual or perennial categories. These categories must be known if you are to be victorious in the fight against them. It is also very important to know the type of lawn and how many square feet of lawn you have.
Annual weeds germinate from seed, grow to maturity, and die within twelve months. Crabgrass is an annual summer weed and henbit is an annual winter weed. Annual weeds are best controlled with a properly timed application of pre-emergent herbicides. If we miss the timing, they can also be controlled with post-emergent herbicides.
Perennial weeds live for more than one year. They can reproduce from stolons, rhizomes, tubers, and seeds. Pre-emergent herbicides are only used to control the spread of seeds but they will not kill the parent. To rid an area of perennial weeds requires a post-emergent herbicide applied during the active growing season. Dallisgrass is a perennial grassy weed and Dollarweed is an example of a broadleaf. The last category is the sedges. The most common in our area is nutsedge. Sedges need to be treated like perennial weeds. To kill the plants, use a post-emergent herbicide that is labeled for the type of sedge you are fighting.
Weed ID: https://aggieturf.tamu.edu/turfgrass-weeds/
