Weeds, Winter Annual

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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.	California burclover (Medicago polymorpha): Pea family; summer annual; seed leaves oblong; first true leaf rounded with single leaflet; later leaves with characteristic clover-like shape.	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.
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.	Common groundsel (Senecio vulgaris): Sunflower family; winter annual; seed leaves narrow, with blunt narrow tip; first true leaves with shallow teeth; third and fourth leaves more deeply lobed.	Filaree (Erodium spp.): Geranium family; winter annual or biennial; cotyledons have long stalks and egg-shaped, asymmetric lobes; leaves form a rosette close to the ground.
Henbit (Lamium amplexicaule): Mint family; winter annual; seedling leaves small, oblong, with smooth margins; first true leaves rounded, coarsely toothed, with visible netted veins.	Little mallow (Cheeseweed) (Malva parviflora): Mallow family; winter annual; seed leaves heart shaped, sometimes with red tinge; true leaves roundish with wavy, shallow-toothed margins. (prevalent due to Round-Up resistance)	Mustards (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.
Rabbitfoot polypogon (Polypogon monspeliensis): Grass family; winter annual; seedling leaves are yellow-green and slender; ligules are membranous, thin, and have a pointy, ragged tip; no auricles; sheaths are open.	Ryegrass (Lolium spp.): Grass family; winter annual or perennial; first blade is long and narrow and stands erect; leaves are rolled in the bud, and ligule is membranous; generally, auricles are present, but may be absent on very young seedlings; blades are about 50 times longer than they are wide and have a shiny, varnished appearance.	London rocket (Sisymbrium irio): Mustard family; winter annual; seedlings narrow with long stalks; margins of first true leaves indented, distinguishing seedlings of London rocket from those of shepherd's purse; seedlings with deeply lobed leaves.
Shepherd's-purse (Capsella bursa-pastoris): Mustard family; winter annual; seed leaves pale green with tiny granules on surface; first true leaves with smooth margins; fourth and later leaves may be indented; true leaves covered with star-shaped hairs.	Sowthistles (Sonchus spp.): Sunflower family; winter annual; seedling has stalked, spoon-shaped seed leaves, rounded at the tip; seed leaves and young leaves often have a grayish-white powdery coating, but later leaves have only a few hairs.	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.
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.