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These annual grasses can produce as many as 150,000 seeds per plant and are very hard to combat. This is not a weed that can be readily pulled, and as a grass, it is not susceptible to broadleaf herbicides. Most of the chemicals that kill crabgrass will also kill all other turf grasses.
Purslane (Portulaca oleracea)
Common plantain (Plantago major) may take you back to your childhood. Did you have a pet bunny as a kid? What did you feed it? If you built a bottomless outdoor cage for your pet (with the cage resting directly on the ground, without legs), your bunny no doubt would eat the vegetation under him. Grass would have been on the menu, but another favorite dish would have been common plantain (if present). Common plantain is also edible by people and may be used in salads or as a cooked green.
Unlike many lawn weeds, this one is indigenous to North America, not a foreign invader.
Common plantain has a broad leaf, but a relative, Plantago lanceolata, has grass-like foliage and is called buckthorn plantain, or ribgrass.
Black Medic (Medicago lupulina)
Appearance: The leaves of barnyardgrass are rolled in the bud and contain neither a ligule nor auricles; the sheath is open but compressed. The mid-vein is thick and keeled; roots are fibrous.
Broadleaf Lawn Weeds
Range: throughout the United States
Perennial or annual, broadleaf
Growth: Speedwells are among the earliest of lawn weeds to appear, greening up as early as late winter. Most are characterized by creeping stems that root at the nodes. Some show an erect growth habit as they mature. They all thrive in cool, moist soils where turf has thinned.