Lawn Care/Basics for Homeowners-Lawn Care/Weed Identification and Control/Classification/Annual Grasses
 Goosegrass or Silver Crabgrass |
| Smooth Crabgrasses and Large Crabgrass |
| Annual Bluegrass |
| Yellow Foxtail |
It is a warm season annual member of the Grass family (Poaceae) that reproduces by seeds, usually emerging a few weeks after crabgrass. Goosegrass is a coarse, bunch-type grass that forms a basal rosette of prostrate to occasionally upright flattened stems up to 2 feet long. The stems do not root at nodes. The root system is fibrous, and the lower portions of stems near the base are silver or white. The leaves of goosegrass are dark green, hairy near the base, and smooth and keeled below. They grow up to 12 inches long and 1/3 inch wide and are either flat or folded. Goosegrass flowers are 2 to 10 flattened, finger-like spikes that each resemble a zipper. They emerge from a common point (windmill) in July to September. This weed occurs in lawns and sports turf areas during the mid to late growing season. It is usually found in full sun and often in poorly drained or compacted soil. Goosegrass tolerates close mowing. To control goosegrass without chemicals, mechanically remove or hand pull. Maintain turf density and health through proper culture, especially during spring and summer. Increase drainage and avoid light frequent irrigation, summer fertilization, and close mowing or scalping. Reduce soil compaction by limiting traffic, especially when the soils are wet; core aerify when the turf is actively growing. Apply preemergence herbicides one to two weeks prior to germination in the spring; use post emergence herbicides when weeds are small.
They are warm season annual members of the Grass family that reproduce primarily by seeds. Large crabgrass can also reproduce by long, rooting tillers. Seeds of both plants can germinate from mid-spring through summer when soil temperatures are greater than 55 to 60 °F for 7 to 10 consecutive days and can continue germinating in soil temperatures to 95 °F. These plants will, reproduce from seeds in the soil throughout much of the growing season when moisture and light are present and soil temperatures are warm. Both crabgrasses are much-branches and upright or prostrate. Large crabgrass is normally mat forming, often has purple stems, and can grow to more than 3 feet in height. Smooth crabgrass is usually 15 inches or less. The leaves of large crabgrass are pale blue green, hairy on both sides, and with margins that may be rough. They are flat, sharply pointed, 1/4 to 2/5 inches wide, and 2 to 6 inches long. Smooth crabgrass leaves are normally dull green, sometimes purple tinged, and with margins that may be rough. They are sharply pointed, sparsely hairy near the base, 1 to 4 inches long, and 1/8 to 1/4 inch wide. Large crabgrass flowers are borne in a raceme with 3 to 13 purplish finger-like spikes up to 6 inches long. They occur in whorls at end of stout stalk during August through September. The flowers of smooth crabgrass are borne in a raceme with 2 to 6 finger-like, purplish spikes up to 4 inches long, and at the end of flowering stalk. They also occur August through September. Both crabgrasses can be found in most warm, moist, fertile lawns in sun where turf is thin or mowed too short. They will tolerate hot, dry, compacted soils after establishment, and may spread aggressively to crowd out desirable grasses. To control without chemicals maintain turf density and health through proper culture; avoid light, frequent irrigation, spring cultivation, short mowing, and summer fertilization. They can also be hand-pulled or mechanically removed. Apply preemergence herbicides prior to germination when soil temperatures stabilize at 50 °F for several consecutive days; post emergence herbicides should be applied when plants are small.
It is a cool season annual member of the Grass family that reproduces by seeds and stolons that root at nodes. Annual bluegrass forms fiborus rots, grows up to 15 inches tall, and develops stems that are prostrate to erect. It may root at lower nodes. The stems are flattened, and sheaths are flattened and overlapping. Leaves of annual bluegrass are apple green, 1/2 to 3/4 inch long, and 1/25 to 1/5 inch wide. They are flat, soft, and both the upper and lower surfaces are smooth. The tip is boat-shaped. Flowers of annual bluegrass are panicles, 1 to 3 1/2 inches long, open and pyramidal. Annual bluegrass can flower at putting green heights. Annual bluegrass occurs on wet, compacted soils, and in cool temperatures. It responds to intense mowing and fertility and lacks tolerance to environmental extremes. To control annual bluegrass without chemicals, maintain turf health and density through proper culture. Avoid overwatering, overfertilization, and compacted soil conditions. Apply preemergence herbicides prior to weed germination in late summer or early autumn. Apply post emergence herbicides during periods of active growth during cool, moist periods.
It is a warm season annual member of the Grass family that reproduces by seeds. Seeds germinate at temperatures between 68 and 95 °F. Yellow foxtail forms a coarse, upright or prostrate, bunch-type grass. It usually branches at the base and may root at lower nodes. Growing up to 4 feet tall, yellow foxtail emerges from a shallow, fibrous root system and normally has flattened stems that are reddish near the base. Leaves of yellow foxtail are flat, smooth, and with margins that are somewhat rough. They grow 2 to 12 inches long and up to 1/2 inch wide. Twisted or spiraled hairs, 1/8 inch long, usually appear near the base on the upper surface. The sheath is flattened with a prominent midvein. The flowers are cylindrical, dense, bristly, and erect. They are 2 to 5 inches long, yellow, spike-like, and appear June to September. yellow foxtail occurs in moist, fertile soils during the mid to late growing season and are often found in new seedings, open turf, or bare spots. To control yellow foxtail without chemicals, mechanically remove or hand-pull. Maintain turf density and health through proper culture; avoid close mowing and summer fertilization. Apply preemergence herbicidesone to two weeks prior to germination in the late spring or summer; use post emergence herbicides when weeds are small.
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Lawn Care/Basics for Homeowners-Lawn Care/Weed Identification and Control/Classification