Jersey the island. The species is the subject of an ongoing programme to save it from extinction in Jersey via a collaboration between States of Jersey, Durrell Wildlife Conservation Trust and Jersey Amphibian and Reptile Group (JARG), with support and sponsorship from several other organisations. The programme includes captive breeding and release, public awareness and habitat restoration activities. Trees generally considered native are the alder ("Alnus glutinosa"), silver birch ("Betula pendula"), sweet chestnut ("Castanea sativa"), hazel ("Corylus avellana"), hawthorn ("Crataegus monogyna"), beech ("Fagus sylvatica"), ash ("Fraxinus excelsior"), aspen ("Populus tremula"), wild cherry ("Prunus avium"), blackthorn ("Prunus spinosa"), holm oak ("Quercus ilex"),
Prunus cerasus Belgium. Prunus cerasus Prunus cerasus (sour cherry, tart cherry, or dwarf cherry) is a species of "Prunus" in the subgenus "Cerasus" (cherries), native to much of Europe and southwest Asia. It is closely related to the sweet cherry ("Prunus avium"), but has a fruit that is more acidic. The tree is smaller than the sweet cherry (growing to a height of 4–10 m), has twiggy branches, and its crimson-to-near-black cherries are borne upon shorter stalks. There are several varieties of the sour cherry: the dark-red morello cherry and the lighter-red varieties including the amarelle cherry, and the popular Montmorency cherry.