What Is Sandspur?
Sandspur, also called sandbur or burgrass, is an invasive and noxious grassy summer annual weed that produces spiny seed pods in the spring and summer if the plant is allowed to mature. These weeds are especially common in the southern United States--from Maryland down to Texas, and across the southwest from Oklahoma into California.
Sandspur weeds (Cenchrus echinatus L.) are different from another common weed with a similar name. The taller weed called Lawn Burweed (Solivia sessilis) also produces prickly burs, but does not grow in mats in the same way sandspur does. Lawn burweed is most commonly found in the southern coastal states. Use the photos in this guide to confirm that you have found sandspur and not a similar weed that may require a different method of control.
Follow along with our sandspur weed guide to learn how to identify sandbur weeds and keep them out of your lawn.
Sandspur Height
Newly sprouted sandspur weeds can be hard to spot among turf grasses and other weeds. After the sandspur matures in the spring and produces full stalks and seeds they become easier to identify. Sandspur stalks can range from eight or nine inches tall to over two feet tall for some varieties. Sandspur weeds can also form mats along the ground if they do not grow upright.
Sandspur Shape
Sandspur can resemble other desirable turfgrass during cooler weather. Sandspur leaves are not hairy, but short (2mm) hairs may appear at the sheaths at the base of each leaf. The sandspur stem is generally round and smooth. The tell-tale signs of a sandspur weed--spiked, round green seed pods--will appear in the late spring and summer. These burs appear in rows along the tips of sandspur stems. Sandspur stems can take on reddish colors at their base.
Leaves and Flowers on Sandspur
Sandspur leaves are narrow and thin, with pointed tips. They are generally smooth, but can have a rough finish.
The flower of a sandspur weed is the spiny bur that grows in spikes or rows along the tips of the stem. The spines along the body of each bur are often flattened, with the spines around the base of the bur more erect in a ring. Each bur contains one to three seeds.
Sandspur Roots
Sandbur weeds have a shallow root system that thrives in sandy type soils. Though the roots do not grow very far into the soil, there is evidence that sandbur seeds can germinate and sprout from as deep as twelve inches in the earth, making the elimination of these noxious weeds even more difficult to achieve.
Some varieties of sandbur or sandspur may take root at lower nodes on the stem, leading to horizontal growth and the potential for the formation of matted clusters of the weed.
When Does Sandspur Grow?
Sandspur grows and "flowers" in the late spring and through the summer. In the case of sandspur, the fruit that is produced during this time is the painful-to-encounter sand bur. It is neither a fruit nor a flower as we usually think of them, but it is the sandspur's way of spreading seed across greater distances, and the easiest way to identify sandspur weeds during warm seasons.