Poisonous! Krushinovye - Rhamnaceae. Folk names: Thrush berries, witch thorn, laxative crush. Parts used: mature fruits. Pharmacy name: fruits of a joster laxative - Rhamni cathartic! fructus (formerly: Fructus Rhamni cathartici). Botanical description. It is a shrub of about 3 heights, with bulging branches. The bark, while it is young, silver-grey, later becomes brown-black. The joster can be easily recognized by the straight prickle, into which the tops of the branches turn. Suprotive leaves with petioles, ovate, glossy, with recessed veins, on the edge of the town-sawn. In the leaf sinuses there are four-membered unremarkable greenish-yellow flowers collected in umbrellas. Rounded fruits the size of a pea develop from them - first green, then they turn black. Blossoms from May to June. Joster is not a very common plant, it grows both in sunny and dry places and on moist soils in the marshy forests. It can be found on ditches and fences, in bushes, in cemeteries, on forest edge