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INSECTS AND MITES DISEASES PLANT CULTURE & MAINTENANCE IPM TOOLS WEED HERBARIUM
UMass Extension Weed Herbarium
 
Common Name: horseweed, marestail
Scientific Name: Conyza canadensis (L.) Cronq., syn. Erigeron canadensis
Family Name: Asteraceae (Compositae) - Aster or Sunflower Family

Identification Notes:

life cycle - winter or summer annual, reproducing by seed

stems - reproductive, upright, tall, very leafy, hairy, branched above growth habit 1, growth habit 2, growth habit 3, seedling 1, seedling 2

leaves - alternate, linear, hairy, toothed margins or sometimes entire, rosette initially, small above, crowded, sessile rosette 1, rosette 2, stem leaves

flowers - heads of white (sometimes very light pink) ray (ligulate) florets and yellow disk (tubulate) florets in center flowers 1, flowers 2

Images:

Conyza canadensis thumbnail 1 Conyza canadensis thumbnail 2 Conyza canadensis thumbnail 3
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Conyza canadensis thumbnail 4 Conyza canadensis thumbnail 5 Conyza canadensis thumbnail 6
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Conyza canadensis thumbnail 7 Conyza canadensis thumbnail 8 Conyza canadensis thumbnail 9 Conyza canadensis thumbnail 10
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