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(Chamaesyce maculata): Spurge family; summer annual;
seed leaves oval, tips roundish, blue green with smooth margin;
first true leaves rounded, leaf surface smooth and dull, dark
green with reddish tinge.
(Amaranthus retroflexus): Pigweed family; summer annual;
seed leaves long and narrow with red undersides; first true
leaves with notched tips and much broader than seed leaves.
(Amaranthus blitoides): Pigweed family; summer annual;
seed leaves narrow, pointed, 6 to 8 times longer than wide,
with magenta undersides; first true leaves broader, with shiny
upper surface and usually magenta-tinged undersides; edges somewhat
(Amaranthus albus): Pigweed family; summer annual; seed
leaves 3 to 5 times longer than wide, bright green on surface,
magenta on underside; first true leaves spatulate, dark green
with wavy margins, red color underneath; midrib with notched
tip and bristle at end.
polymorpha) Pea family; summer annual; seed leaves oblong; first true
leaf rounded with single leaflet; later leaves with characteristic
(Echinochloa crus-galli) Grass family; summer annual;
first leaf dull gray green; stem flattened, purplish; no ligule.
(Polygonum arenastrum): Knotweed family; summer annual; seed
leaves are long, very narrow, rounded at the tip and light
green with a white cast; true leaves are much broader, emerging from
an encircling, membranous sheath at the leaf base.
(Portulaca oleracea): Purslane family; summer annual; seed leaves oblong,
somewhat club shaped, succulent, maroon on lower surface, and green or maroon
on upper surface; young leaves smooth, succulent, oblong, green on upper surface,
maroonish underneath, and broadest around leaf tip, with short petioles.
(Conyza canadensis): Sunflower family; summer annual; seed leaves dull
green, oval with fine hairs, and with short stalks that sometimes may be tinged
brown purple; first true leaves covered with hairs on upper surface and margins;
undersides of early leaves smooth.
(Conyza bonariensis): Sunflower family; summer annual; seed leaves gray
green; first leaves narrow and covered with short, soft hairs; often wrinkled
(Ipomoea spp.): Morningglory family; summer annual; seed leaves deeply
notched; heart-shaped first true leaves with deep lobes at base; stem below seed
leaves maroon at base and green toward leaf tip.
(Digitaria sanguinalis): Grass family; summer annual; first leaf blade
linear to lance shaped, with stiff, jagged, and papery ligule; hairs on margins
of the collar wide; no auricles; leaves covered with coarse hairs; leaves rolled