1. UC IPM
Cotyledons (seed leaves) of Italian thistle, <i>Carduus pycnocephalus,</i> are hairless, dull, and oval-shaped. True leaves are prickly and toothed.
Cotyledons (seed leaves) of Italian thistle, Carduus pycnocephalus, are hairless, dull, and oval-shaped. True leaves are prickly and toothed.
Credit: Joseph M. DiTomaso