Hoary Cress (Whitetop) (Cardaria draba) has occupied a spot on the Utah Noxious Weed List since its first drafting. Whitetop or Hoary Cress is a perennial mustard that grows up to 2 feet tall. The leaves are blue-green in color. Only the lower leaves are stalked; the others are stalkless and clasp the stem with 2 earlike lobes. The short, flowering branches bear many very small flowers (right photo), each with 4 petals about l/8 inch long, giving the plant a flattop appearance. The white flowers occur only at the terminal ends of the stem. Seeds are formed in a pod. Hoary cress, introduced from Europe and Western Asia, forms large patches in cultivated fields, gardens, pastures, along roadsides and waterways and is very competitive with native vegetation. |
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