Lawn Care/Maintenance/Weed 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 herbicides one to two weeks prior to germination in the late spring or summer; use post emergence herbicides when weeds are small.
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