Weeds
Here are some of the most common American weeds.
Dandelion - Taraxacum officinale
Perennial; spreads by seeds; height to 1 foot; found in U.S. (not southernmost TX, CA, AZ, and FL) and southern Canada; can flower at any time when temperatures permit.
Dig out the entire taproot, hoe plants before they flower, and spread corn gluten in early spring to suppress seedlings.
Annual sowthistle - Sonchus oleraceus
Perennial; spreads by seeds; height to 18 inches; found across U.S. and southern Canada,
mostly in lawns; flowers July through October.
Dig out entire root, or cut at soil line until root stops sprouting. Aerate and add organic matter to lawn.
This weed tolerates compacted soil and shade.
Carpetweed - Mollugo verticillata
Annual; spreads by seeds; stems grow to 1 foot; found across U.S., except for ND and parts of MT and MN; flowers June through November.
Hoe or pull plants when they appear. Mulch deeply to smother any seedlings.
Large crabgrass - Digitaria sanguinalis
Annual; spreads by seeds/roots at leaf joints; height to 3 feet; found across U.S., except ND and parts of SD, MT, and MN; flowers June through October.
Pull out entire plant, including roots. Mulch or let grass grow to 3 to 4 inches high to prevent seed germination. Mowing will not kill this plant. Spread corn gluten in early spring to suppress seedlings.
Poison ivy - Rhus radicans
Perennial; spreads by creeping rootstock; found across U.S. (not AK or CA) and southern Canada, as vine or shrub; flowers in May and June.
Entire plant is toxic. Wear protective gloves and clothing. Cut plant at base, let it dry out, and bury or put vines in trash. Do not compost or burn (inhaling smoke can be fatal). Mulch with cardboard.
Prickly lettuce - Lactuca serriola
Annual/biennial; spreads by seeds; height to 5 feet; found across U.S. except southernmost FL; flowers July through September.
Hoe or pull plants as you see them, or cut taproot below soil line. Wear gloves. Attracts beneficial insects and so may be fine for outlying areas, but can play host to lettuce diseases.
