Bull thistle (Cirsium vulgare) is another aggressive, noxious weed to watch out for. Discover more invasive flowers you may ...

The ones with small flowers are Italian thistle (Carduus pycnocephalus); those with the larger round flower are bull thistle (Cirsium vulgare). And there is some yellow-flowering star thistle ...

• Bull/spear thistle (Cirsium vulgare) leaves are dark green with deeply toothed leaf margins, thorns on leaves and stems and stiff hairs on the leaves.It also has a tap root that can be cut ...

In Illinois, there are several species of invasive thistles, including Canada thistle, Cirsium arvense; bull thistle, Cirsium vulgare; and musk thistle, Carduus nutans.

Creeping thistle (Cirsium arvense) and spear thistle (Cirsium vulgare) are two of just five weeds labelled “injurious” under The Weeds Act 1959.

Cirsium vulgare is a biennial that tends to appear on neglected ground and in arable fields. The seeds from which it reproduces are soft and cotton-like, dispersed on the wind.

Blackgrass, an annual grass that is non-native to Ireland, has been designated as a noxious weed for the first time. Agriculture Minister Martin Heydon has listed blackgrass in a new statutory ...