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Winter Annual Weeds

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  • Volunteer barley
  • Wild oats
  • Burning nettle
  • Mustards
  • Wild radish
  • Annual bluegrass
  • Prickly lettuce
  • Common chickweed
  • Volunteer wheat

The weeds shown here may be seen in fall-planted corn seedlings. For weeds in spring-planted corn seedlings, see common summer weeds. Names link to more information on identification and biology.

Click on photos to enlarge
Several Hordeum species have long claw like auricles.
Volunteer barley
(Hordeum murinum ssp. leporinum): Grass family; winter annual; papery ligule with long and narrow clasping auricles; hairy foliage.
Mustard seedling.
(Brassica spp.): Mustard family; winter annual; all mustard seedlings with broad seed leaves and deep notch at tip; first true leaves bright green on the upper surface and paler below.
Seedling of prickly lettuce.
Prickly lettuce
(Lactuca serriola): Sunflower family; winter annual or biennial; seed leaves about 2 times longer than wide; first true leaves with rounded margins; injured tissue bleeds milky white latex.
Seedling of wild oat.
Wild oats
(Avena fatua): Grass family; winter annual; first leaves with small marginal hairs and counterclockwise twist when viewed from above; ligule large, papery, and pointed.
Wild radish seedling.
Wild radish
(Raphanus raphanistrum): Mustard family; winter annual; seed leaves broad with deep notch at tip; first true leaves irregularly lobed and sometimes with separate lobes at leaf base; seedlings similar to mustards in genus Brassica, but duller green and rougher textured.
Seedling of common chickweed.
Common chickweed
(Stellaria media): Pink family; winter annual; seed leaves with prominent midveins, about 4 times longer than wide, tapering to point at tip; true leaves broader, opposite, and yellow-green.
Burning nettle seedling.
Burning nettle
(Urtica urens): Nettle family; winter or summer annual; rounded seed leaves with smooth margin and small notch at tip; first true leaves with small notch at tip, opposite, stalked, and distinctly toothed.
Annual bluegrass seedling.
Annual bluegrass
(Poa annua): Grass family; winter annual; leaf tip shaped like bow of a boat; membranous ligule rounded with slightly pointed tip; leaf blade crinkled at midsection.
Collar regions of (left to right) barley, wheat, and oat.
Volunteer wheat
(Triticum aestivum): Grass family; winter annual; distinguished from most other grasses by ligules that clasp stem with slight overlap; barley plant ligules longer, with more overlap.

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