| Weed |
Annual
bluegrass |
| Scientific
Name |
Poa
annua |
| Family |
Grass family (Poaceae) |
| Life
Cycle |
Winter
annual or biennial |
| Reproduction
Method |
Reproduces
by seed, and stolons that root at nodes |
| Appearance |
Annual
bluegrass forms fibrous roots, grows up to 15 inches tall, and develops
stems that are prostrate to erect. It may root at lower nodes. The stems
and sheaths are flattened and the sheaths are also overlapping. |
| Leaves |
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 |
Flowers
of annual bluegrass are panicles, 1 to 3 1/2 inches long, open and pyramidal.
Annual bluegrass can flower at putting green heights. |
| Occurrence |
Annual
bluegrass occurs on wet, compacted soils, and in cool temperatures. It responds
to intense mowing and fertility and lacks tolerance to environmental extremes.
|
| Non
Chemical Control |
To
control annual bluegrass without chemicals, maintain turf health and density
through proper culture. Avoid overwatering, over fertilization, and compacted
soil conditions. |
| Chemical
Control |
 |
 |
| Application
Period |
Apply
preemergence herbicides before weed germination ion late summer of early
autumn. Apply postemergence herbicides during periods of active growth during
cool, moist periods. |
| Active
Ingredient in Labeled Products |
Preemergent
|
Postemergent
|
- benefin
- bensulide
- dithiopyr
- ethofumesate*
- oxadazon
- pendimethalin
- prodiamine
- trifluralin
*Early postemergence as well |
|
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| Notes |
|
(Click
on Image to Enlarge and Sharpen Photograph)
|
Annual
bluegrass plant
|
Annual
bluegrass plant in sidewalk
|
Annual
bluegrass in Kentucky bluegrass
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Annual
bluegrass tiller
|
Annual
bluegrass ligule
|
Annual
bluegrass adjacent to Kentucky bluegrass
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| Confused??
Look-a-Likes |
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