Common Name: horseweed
Species: Conyza canadensis (L.) Cronq.
Bayer Code: ERICA

Horseweed is a winter or summer annual found in waste areas, roadsides and turf. It can vary greatly in height according to the soil it grows in, and the immature rosette looks much different than the mature plant. The erect stem is usually hairy, and is generally branched near the top with small inconspicuous white flowers. The lower leaves are 1 - 4 inches long and toothed, while those scattered along the stem are narrow and smooth. From June to November the plant produces numerous heads of small, inconspicuous white flowers, followed by an abundance of seed.
field of horseweed
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horseweed seedling
Growth Season summer annual weed OR winter annual weed 
Growth Habit upright OR rosette 
Leaflet Number one 
Leaf Margin serrated/toothed OR smooth 
Leaf Hairs upper/lower surface 
Leaf/Leaflet Shape linear/oblong OR oval/egg-shaped/elliptical 
Leaf Width <1/2 inchleaves along stem on the mature plant are about 0.4 inches (10 mm) wide
Leaf Venation   
Leaf Arrangement alternate OR whorled or basal rosette 
Root Type   
Flower Color white