Perennial Sunflowers

Helianthus spp.

Asteraceae (Aster Family)

▲ flowering perennial sunflower (Maximillian  or Sawtooh Sunflower?)

▲ perennial sunflower foliage

▲ perennial sunflower flowers

▲ ▼  more flowering perennial sunflowers

▲ ▼ foliage and flowers of Ashe Sunflower (?)

Perennial Sunflowers:  Maximilian Sunflower, Sawtooth Sunflower, Western Sunflower, Willowleaf Sunflower, Jerusalem Artichoke: (pp. 144-147, Weeds of the Great Plains; pp. 146-147, Weeds of the Northeast)

·         all are creeping perennial weeds that form rhizomes that allow them to spread to form colonies with  maturity

·         most are palatable to livestock, except in fertile soils, where high nitrate accumulation may cause poisoning, but may be seen as weedy in reduced tillage crops

·         once established, these species can be hard to control

·         most produce relatively tall (4-8’), unbranched, leafy stems with linear to ovate/triangular, rough-textured leaves

·         flowers are in terminal clusters in late summer to early fall, with yellow ray flowers and yellow to brown disk flowers; total flower diameter is usually 2-4”