Sorbus pseudomeinichii 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 in Scotland and also the United Kingdom. A third was recorded as a sapling but is believed to have been destroyed by deer. A seedling has also been grown in
Sorbus aucuparia in an alternate leaf pattern on a branch., distinguishing them from those of ash, "Fraxinus excelsior", which are opposite and without stipules. The leaflets are elongated-lanceolate in shape, 2 to 6 cm long, and 1 to 2.5 cm wide with a sharply serrated edge, and have short stems or sit close to the central vein except for the outermost leaflet. Leaflets are covered in gray-silvery hairs after sprouting but become mostly bare after they unfold. Their uppers side is dark green and their underside is a grayish green and felted. Young leaflets smell like marzipan when brayed. The leaflets are