The aspen is a forest tree, occurring widely throughout the whole of Europe, and extending beyond the Arctic Circle in the north. In central Europe it grows in lowland and on mountains up to and above 1000 metres; it is most plentiful, however, in hill country, coppice forests and forests which are clear-felled.

The black poplar is a tree of riverine forests and requires abundant light and a high level of underground water for good growth. In commercial forests it is today being replaced by the Carolina poplar (Populus canadensis Moench.), a hybrid between the black poplar and the northern cottonwood (P. deltoides). It is distinguished by rapid growth and is cultivated in plantations. The black poplar produces abundant stump suckers and is also propagated by cuttings. The pyramidal form Populus nigra italica (syn. pyramidalis), the Lombardy poplar, is widely planted in parks and alongside highways. The light wood is used to make plywood and cellulose.

The balsam poplars are indigenous to North America and Asia. The one most commonly cultivated in Europe is Populus balsamifera L., a native of North America, where it grows on alluvial bottomlands in the northern United States and in Cahada. The name is derived from the pleasant balsam smell of the opening buds and leaves. It grows to a height of 30 metres and has yellow-grey bark, thick and furrowed, and coloured blackish at the base of the trunk.

The white poplar grows in moist lowland woods, sometimes by the waterside. It extends from Spain through central Europe to southern Siberia, growing to heights of up to 30 metres. It has a thick trunk topped with a broad rounded crown, and the bark is smooth and greyish, but blackish and fissured at the base. The annual shoots are covered with whitish-grey down, including the small buds. The dioecious flowers appear at the end of March and the seed capsules burst in May.

In Europe it is cultivated mainly in parks for its ornamental, light-coloured bark and pleasant scent in spring. Planted occasionally in hill country is the western balsam poplar (Populus trichocarpa Torr. et Grey), a native of western North America. A northern Chinese poplar (Populus simouii Carr.), a native of China and Manchuria, is more frequently planted as a street and shade tree in European cities.

The juniper is highly valued in forestry as a pioneer and to prevent soil erosion. In garden landscaping its dwarf forms are mainly used in rock gardens. The high quality wood is of little importance since the tree is of such small dimensions. The berries are used for flavouring gin and seasoning food.