Sorbus pseudomeinichii of the location. The species is named after Glen Catacol where it was found and one of the two surviving plants is thought to be more than fifty years old. Sorbus pseudomeinichii Sorbus pseudomeinichii, known as false rowan and Catacol whitebeam, is a rare tree endemic to the Isle of Arran in south west Scotland. It is believed to have arisen as a hybrid of the native rowan ("Sorbus aucuparia") and the cut-leaved whitebeam ("Sorbus pseudofennica") which is in turn a rowan/Arran whitebeam ("Sorbus arranensis") hybrid. Only two specimens of the Catacol whitebeam are known, making it the rarest tree
Sorbus aucuparia a light brown to reddish brown heartwood. It is diffuse-porous, flexible, elastic, and tough, but not durable, with a density of 600 to in a dried state. The roots of "S. aucuparia" grow wide and deep, and the plant is capable of root sprouting and can regenerate after coppicing. The compound leaves are pinnate with 4 to 9 pairs of leaflets on either side of a terete central vein and with a terminal leaflet. There are paired leaf-like stipules at the base of the petiole. The leaves are up to 20 cm long, 8 to 12 cm wide, and arranged