File:Hypericum perforatum leaf3.jpg

English: Introduced, warm-season, perennial, prostrate to erect, woody herb or shrub to 1 m tall. Stems are reddish, hairless, with weak opposite longitudinal ridges; they arise from rhizomes or woody crowns. Leaves are opposite, sessile, hairless, to 3 cm long and have many translucent dots (oil glands) that are easily seen when held to the light. Flowerheads are panicles or corymbose cymes. Flowers are numerous and 15-20 mm wide. Petals are yellow and have black glands on their edges. Styles are 3-branched. Fruit are sticky 3-valved capsules, 5 to 10 mm long. Flowers in late spring and summer. Found in neglected pastures, sparse bushland and disturbed areas. Tiny seeds spread by water and in soil, hay and livestock. Sticky fruits adhere to animals; long runners spread from crowns. Causes photosensitisation and numerous other disorders in livestock; animals tend to recover once removed. Established plants are very competitive and are best controlled by herbicides or, if suitable, by cultivation. Introduced insect (Chrysolina beetles) and mite (St John’s wort mite ) predators provide good levels of control in many areas. Promote dense, healthy pastures to compete with seedlings, which are not robust.