University of Missouri Extension

IPM1007, Revised November 2009

Practical Weed Science for the Field Scout: Corn and Soybean

Sunflower, common (Helianthus annuus)

Summer annual broadleaf

SunflowerSunflower
Sunflower

A stout summer annual that may reach as much as 9 feet in height with large yellow flowers. Seedlings have cotyledons that are relatively large and oval in outline. First true leaves are lanceolate with toothed margins. Mature plants have leaves that are alternate, rough and hairy, with toothed margins. Lower leaves occur on long petioles. Flower heads are robust and can range from 1 to 5 inches in diameter. Many outer yellow petals enclose the reddish brown disk flowers inside.
 

 

Wild thing
 

IPM1007 Practical Weed Science for the Field Scout: Corn and Soybean | University of Missouri Extension

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