Aspen (Populus tremula)
Aspen is a deciduous broadleaf tree native to the UK and most of Europe.
Common name: aspen, quaking aspen
Scientific name: Populus tremula
UK provenance: native
Interesting fact: the scientific name 'tremula' means to 'tremble' and refers to the way the leaves flutter and move in the slightest breeze.
What does aspen look like?
Overview: also known as quaking aspen, it is a beautiful tree with shimmering foliage. Mature trees grow to 25m. Older trees may be covered with lichen, which gives the trunk a black appearance, and the bark is grey and often pitted with diamond-shaped pores, called lenticels. The uppermost branches are often bent over horizontally. Twigs are dark brown, slender and shiny.
Leaves: round with large, irregular blunt teeth. The leaf stalks are flattened and flexible near the leaf blade, which is why the leaves flutter so easily. Young leaves are coppery coloured before becoming green, then turn a vibrant yellow or occasionally red before falling in autumn.
Flowers: aspen is dioecious, meaning male and female flowers (catkins) are found on separate trees, in March and April
Fruits: once pollinated, female catkins ripen to release tiny fluffy seeds in summer. Aspen can also propagate itself by suckers.
Look out for: leaf stalks (petioles) are flattened. Twigs are very knobbly.
Could be confused with: other poplar species, such as black poplar (Populus nigra).
Identified in winter by: poplar twigs, especially older ones, are very knobbly. Buds spiral around and are closely pressed to the twig.
Where to find aspen
Native to cool regions in the northern hemisphere, aspens grow in clonal colonies, particularly in ancient woods and heaths and also on well drained soil near rivers. It flourishes in open sunlight and moist soil and is intolerant of shade. It is most common in the north-west of Scotland.
Value to wildlife
Aspen trees attract a wide variety of insects, including two gall midges and the aspen hoverfly, which feeds in dead aspen wood. These insects provide a variety of food for predators such as bird and ladybirds. Deadwood cavities provide nesting opportunities for birds such as the woodpecker. Aspen is a preferred species for beavers, which are native to the UK.
Mythology and symbolism
A crown made of aspen leaves was said to give its wearer the power to visit and return safely from the Underworld. Aspen crowns found in ancient burial mounds may have been included to allow the spirits of the deceased to be reborn. Aspis, the aspen's Greek name, means shield, which was one of the many traditional uses of its wood.
How we use aspen
Aspen wood is lightweight, and was used for making oars and paddles, surgical splints and wagon bottoms.
Poplar species can be prone to a variety of fungal diseases, including cankers, leaf rusts and poplar scab.