Forest Burr is a perennial herb, erect or prostrate and sprawling, 60-90 cm tall. Branches and leaves opposite, variously hairy. Leaves variable in shape and size, from narrowly ovate-elliptic to oblong or orbicular, 2-12 x 1-6 cm, acuminate to apiculate at the tip, shortly or more longly wedge-shaped at the base, narrowed to a stalk 2-25 mm long. Flower-spikes are at the end of the stem and branches, at first dense, elongating to as much as 50 cm in fruit. Inflorescences greyish-white, in racemes, the clusters alternate and well-spaced. hermaphrodite flowers mostly in ± sessile clusters of 3, upper often solitary; bracteoles of hermaphrodite flowers broadly cordate-ovate, 2.75-5 mm, conspicuous, sharply mucronate with the percurrent midrib. Tepals oblong, 3.5-6 mm, glabrous to ± pilose dorsally, 3-nerved, the lateral nerves of the 2 outer tepals strong throughout, joining the shortly excurrent midrib just below the apex. Spines of modified flowers glabrous except sometimes near the base, yellowish to purple, 3-4 mm; 3-flowered clusters falling together to form a “burr” up to 2.5 cm in diameter. Filaments 2-3 mm. Style slender, 1.25 2 mm. The fluffy fruits are balled and used to filter milk etc.