Flower:

A single round to oval flower head on a short stalk arising from a leaf axil. Heads are about ½ inch long, densely packed with tiny yellow pea-shaped flowers that turn a creamy color then rusty brown before going to seed, giving plants a somewhat calico appearance. A plant has 20 to 40 flowers in a head and numerous flower heads on branching stems.

Leaves and stems:

Leaves are compound in 3s on a stalk about ½ inch long. Leaflets are ½ to ¾ inch long, finely toothed except near the base, rounded at the tip and tapering at the base, with a distinct stalk on the middle leaflet and the other 2 leaflets stalkless. A pair of leafy appendages (stipule) at the leaf joint are oval with a pointed tip and about half the length of the leaf stalk. Stems are covered in fine hairs; growth habit is spreading with many branches.

Notes:

This weed was introduced as a “soil improvement” and forage crop and quickly escaped cultivation. It is more widely distributed within the state than the very similar Golden Hop Clover (Trifolium aureum). As its name suggests, Low Hop Clover has a lower growth habit but the most distinguishing characteristic is that the central leaflet has a distinct stalk where Golden Hop Clover leaflets are all stalkless. Also similar is Black Medic (Medicago lupulina), another low growing weed with round yellow flower heads, but its flowers are about half the size of Low Hop Clover.