Bull Thistles


BULL THISTLES
How to Identify Bull Thistles:
Leaves: First-year basal rosette leaves can be 20” long  or  longer.  Stem leaves  are  alternate,  stalkless,  lance-shaped, and coarsely lobed;  lobes are tipped with stout spines.  Musk smooth and hairless on both sides.  Plumeless  - smooth above, hairy below.  Bull  - spiny above, white woolly hair below.
Flowers:
Flower heads are brush-like, pink to purple, single or clustered at end of stem.  Musk  -  1.5-3”across; solitary; usually bent over or “nodding” on smooth stalk. Plumeless and  bull  -  0.5-1”  and  1.5-2”  across  respectively;  on winged stems; bracts with spiny tips. All bloom May-August.
Control:


•Manual/Mechanical:  Use sharp shovel to cut 1-2” below the soil surface. Mow (minimum 2-3 times per growing season) when flower buds are about to open to prevent seed production. The roots ball of thistles can be easily dug out after rain.

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