| Plant Photo | Scientific Name | Common Name and Description | Seed Photo |
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Amaranthus spinosus | Common Name: Spiny Amaranth or Pigweed
Leaves: Alternate, ovate-lanceolate to ovate, glabrous to sparingly pubescent (covered with short hairs - downy), 3-10 cm long Flowers: Male and female flowers, occasional flowers perfect, spikes numerous, 5-15 cm long Fruit: Black, nearly round, 0.7-1 mm in diameter Habitat: In waste ground, sandy loamy soil Range: East third of Texas, west to Dallas, Travis and Cameron counties Group: Dicot Family: Amaranthaceae Growth Habit: Forb/Herb - weedy, long (to 4 dm taproot), stems stout and succulent, erect, branched, 3-12 dm tall Duration: Annual U.S. Nativity: Probably tropical in origin (Correll and Johnston); Native (USDA) |
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Ambrosia trifida | Common Name: Giant Ragweed
Leaves: Alternate or opposite at the lower nodes, in some species opposite nearly throughout, entire or palmately lobed or (usually) pinnately lobed or dissected Flowers: Ray flowers absent, lacking pappus and corolla, phyllaries fused about flowers to form a hard indehiscent nutlike receptacle Fruit: Brown achene ~4 mm Habitat: Abundant in seasonally moist stream bottoms and overflow areas Range: Throughout the eastern and northern halves of Texas; the midwest, and the central United States to the Rocky Mountains and from southern Canada to northern Mexico Group: Dicot Family: Asteraceae Growth Habit: Subshrub/Forb/Herb - tall erect annual taprooted herb 1-3 meters tall, stem angled, striate and scabrous Duration: Annual U.S. Nativity: Native |
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Helianthus annuus | Common Name: Sunflower
Leaves: Leaves always opposite at least at the base of the stems and usually alternate above, ovate, obtuse or less commonly acute and coarse-textured Flowers: Disc 3-5 cm across, rays 21-35 are 3-5 cm long and 10-15 mm broad Fruit: A dark achene with white stripes 4-7 mm Habitat: Fields, borders, waste places and gardens Range: Rare in northeast Texas; found in the east and central United States and south Canada Group: Dicot Family: Asteraceae Growth Habit: Forb/Herb - taprooted annual, stems 5-25 dm tall Duration: Annual U.S. Nativity: Native |
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Iva annua | Common Name: Annual Marshelder or Sumpweed
Leaves: Alternate or opposite 3-12 cm long, ovate or becoming lanceolate upward Flowers: Staminate flowers 9-17, corolla about 2.5 mm long, pistillate flowers 3-5, corollas about 1.5 mm long Fruit: Achenes 2-4.5 mm long, brown, broadly ovate, lenticular Habitat: Fields, borders, waste places and gardens Range: East half of Texas, west to Wheeler, Taylor, Travis, DeWitt and Hidalgo counties; most of the eastern United States, west to Nebraska, Kansas, Oklahoma and Texas Group: Dicot Family: Asteraceae Growth Habit: Forb/Herb - taprooted 4-20 dm tall Duration: Annual U.S. Nativity: Native |
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Chenopodium album | Common Name: Pigweed, Goosefoot, Lamb's-Quarters, or Wild Spinach
Leaves: Oval-rhombic, rarely ovate or lanceolate, 2.5-8 cm long, usually conspicuously longer than broad, obtuse or rounded and apiculate at the apex, often shallowly 3-lobed, pale-green and glabrate above, densely farinose beneath Flowers: Flowers in large glomerules, terminal stout erect or ascending paniculate spikes to 3 dm long, grayish-green Fruit: Black, 1.1-1.5 mm broad, nearly smooth to minutely pitted Habitat: Fields, fencerows and waste places. Range: Newfoundland to Florida, west to Yukon and British Columbia, south to Mexico and South America, also in North Africa Group: Dicot Family: Chenopodiaceae Growth Habit: Forb/Herb - pale-green, sometimes turning reddish, 6-30 dm tall Duration: Annual U.S. Nativity: Eurasian (Correll and Johnston); Native and Introduced (USDA) |
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