Colony forming perennial that reproduces by seeds and root buds on spreading lateral roots. Germinating root buds do not have cotyledons. First true leaves are ovate with soft spines. The degree of lobing, length of spines and the amount of pubescence varies between plant. Has upright stems which can be woody and grow 30cm to 2m tall.
Stems are thin and green without spiny wings and are highly branched above.
Leaves are alternate and lance shaped with irregular lobes, and spines. Mature plants have deep and extensive horizontal roots. Flowers are unisexual with male and female flowers on separate plants.