Pursuit, Scepter) in 1992. Kansas State … Powell amaranth leaf (middle). Here are some key distinguishing features: Palmer amaranth and waterhemp have smooth stems and petioles with few or no hairs. So you’ve found a suspicious seedling. Flowers. In general, common waterhemp has oar-shaped seed leaves while redroot and smooth pigweeds have long, narrow seed leaves. Smooth Pigweed (Amaranthus hybridus), and Velvetleaf (Abutilon theophrasti)l REX A. LIEBL and MICHAEL A. NORMAN2 Abstract. By the time a Palmer amaranth seedling has eight to 10 leaves, it is already showing key differences between other lookalike weed species, like waterhemp and redroot pigweed… W069 • First leaves are rounded with small notch at leaf tips. Similar weeds Powell amaranth (A. powellii S. Cotyledons (seed leaves) are long and narrow and are often red underneath. Seedlings of all common pigweeds are similar. Seedling stems are red to green, smooth and hairless to slightly hairy. Powell amaranth seed-head. Pigweed identification can be difficult, especially at the seedling stage of growth. Plants are erect and usually around 3-4' in height, although they can grow larger. Pigweed Seedling https://bsi.ce.ufl.edu/ What Is Pigweed Used For. Revised: 5/11/2010 Item number: NCR607 . Based on chlorophyll content, hydroponically cultured soybean seedlings were 254, 66, and 13 times more tolerant to clomazone than velvetleaf, corn, and smooth pigweed, respectively. The Leaves are alternate, dull green, egg- to diamond-shaped with a small notch at the tip, smooth to wavy margins and long petioles. Smooth and redroot pigweed are difficult to distinguish until flowering stage. Widespread, but mostly a problem in the Great Plains. Seedling Shapes Pigweed seedlings differ in shape. Figure 3. It is divided into two main sections: grass and grass-like weeds and broadleaf weeds. The shapes of cotyledons and first true leaves are important in weed identification. Leaves are hairy beneath, at least on the whitish veins. As seedlings and young plants, they can be difficult to distinguish from our more common redroot and smooth pigweeds. Leaves . Redroot and/or smooth pigweed seedlings with fine hairs present on the stem and leaf surfaces. (Figure 2) • Leaf and stem surfaces are rough. Pigweed is the common name for a number of plants contained in the genus Amaranthus. the seedling, expand and become the first visible leaves. Identifying Pigweed, redroot . A smooth pigweed population in Ballard County, Kentucky was suspected of having developed resistance to the imidazolinone herbicides (i.e. Leaves are round to oval in shape and have prominent veins; both leaves and stems are covered in fine hairs (pubescent). In addition, the pigweeds: Palmer amaranth, waterhemp, redroot pigweed, Powell amaranth, and smooth pigweed, are not easily separated by species at the immature stages.