Goosegrass information

Goosegrass Takes Prize: Ugliest Turf Weed In 2018
Peter H. Dernoeden, Ph. D.

It has been a tough growing season, but this is not so unusual in the mid-Atlantic. A cold, windy and wet spring slowed green-up, and for some, was associated with major losses of bermudagrass cover. Hot and dry conditions were followed by deluges of rain, which beat-up turf badly. These same conditions are, in part, responsible for major goosegrass invasions. Weather conditions promoted rapid breakdown of otherwise effective preemergence herbicides targeting goosegrass, and loss of density gave goosegrass an even greater competitive advantage, especially on golf tees and approaches. Goosegrass, also known as silver or hard crabgrass, is a warm-season annual that germinates in spring and becomes a highly invasive and tough competitor, especially in compacted soils. Goosegrass seedlings emerge in spring about 2 to 3 weeks after crabgrass. Goosegrass can develop in higher cut turf grown on a well aerated soil, but it is most common in compacted soils.  Goosegrass tolerates very low mowing and survives extreme heat and drought stress. Low cut sports turfs, and golf course greens, tees and fairways are primary sites for goosegrass invasion. Compacted paths on school lawns, parks and similar sites often are colonized. Goosegrass also can be a huge problem in sod fields, especially in areas adjacent to where heavy equipment enters and exits fields, as well as along drainage ditches.

Goosegrass rosettes with silver-colored stems in the center.

Goosegrass leaves are smooth to sparsely hairy on both surfaces and stems are flattened. During summer, goosegrass plants rapidly tiller. Leaves are dark green and have silvery-white stems in the center of the plant, which  lie flat or appressed  on the ground.  Tillers spread out to form a rosette similar to the spokes of a wheel. Plants become anchored by a deep tap-like root, making them difficult to pull out of turf. Seedheads consist of 2 to 10  radiating finger-like spikes that develop at the top of the seed stalk. Two rows of alternating, flattened seeds appear silvery-white and “zipper-like.

Appressed, silver- centered tillers of numerous goosegrass plants in a bentgrass tee

Goosegrass spikes with 2 rows of flattened, alternating seeds that appear whitish-silver; August,

Goosegrass plant with deep tap root from a green.

Shredded and bleached goosegrass leaves and stems on a tee; August 2018.