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Creeping thistle, Cirsium arvense, spreads primarily through vegetative means and secondly by seed.
The thistle root systems, rhizomes, can grow by 4-5m horizontally in one season.
Soil disturbances such as plowing increase thistle growth, as small surviving rhizome fragments can produce clones up to 2.8m across.
Creeping thistle is often called Canada thistle, though it is not actually native to Canada but comes from Europe.
Every spring the root system of the thistle sends up shoots that reach 1-2m high upon maturation.
Creeping thistle is considered an invasive species and a noxious weed all across North America.
The leaves of creeping thistle are crinkled at the edges and have sharp spines that protrude at the vertices of the fold.
Figures 15 & 16 creeping thistle diagrams
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