Amelasorbus jackii

x Amelasorbus jackii, also known as Jack's Amelasorbus, is a natural hybrid resulting from a cross between two distinct genera: Amelanchier and Sorbus. The result is a small tree reaching a height of 2 to 2.5 meters, with characteristics borrowed from both parents. Its flowering in May covers the tree with small star-shaped white flowers, similar to those of the Amelanchier. Its elliptical foliage is dark green and turns orange in autumn. It produces round brown "pyriform" fruits, borrowing from both genera.

x Amelasorbus jackii is the result of a quite rare intergeneric hybridisation phenomenon. The two parents are Amelanchier alnifolia, alder-leaved Amelanchier, and Sorbus scopulina. Both belong to the Rosaceae family and are native to North America, but they are different genera. x Amelasorbus jackii is the only accepted species. The first discovered and described specimen was by Alfred Rehder from the Arnold Arboretum in 1925, in Idaho, in the northern United States. It forms a small tree, reaching a height of 2 to 2.5 meters. Its deciduous leaves with petioles are elliptical to ovoid. They measure from 4 to 10 cm and are dark green with a medium green underside. In autumn, they turn orange. The flowering occurs throughout the month of May, with solitary star-shaped flowers measuring 4 to 5 cm in diameter, and white. The fruits, called "pyriforms," are complex seeded fruits, consisting of the floral receptacle becoming fleshy and fused to the ovary. They are brown.

Jack's Amelasorbus is a sturdy shrub that adapts to acidic, neutral, or slightly alkaline soils, in full sun or partial shade. It appreciates a fertile, well-drained soil that is moderately moist to reasonably dry. It can be planted as a country hedge or in the background of a flower bed. It pairs well with ornamental apple and cherry trees, deciduous Euonymus, Japanese quince, spring-blooming Spiraea, hawthorns, loquat, Prunus, and many others.