Aspen, common aspen, Eurasian aspen, European aspen, quaking aspen
Aspen, common aspen, Eurasian aspen, European aspen, quaking aspen (Eng), álamo temblón, temblón (Spa), trèmol (Cat), lertxuna (Baq), álamo tremedor (Glg), choupo-tremedor (Por).
“And there is the quaking aspen [...], ‘Populus tremula, that quivers even with no breeze, and which seems to have a fluid mobility able to produce the gusts itself with its tiny castanets...”.
‘Nuevo viaje de España’, Víctor de la Serna
This is a slender, elongated, deciduous tree which can be up to 30 m tall. It has greenish bark that becomes greyish and cracks with age on the lower areas of the trunk. The leaves are simple and alternate (this character is seen best in the middle of the branches, as at the ends they sometimes appear very close together). Adult leaves are hairless, rounded and irregularly toothed or pointed, but always with blunt tips. The stalk is very long and flat in cross-section. In autumn the leaves change from light green to purple, passing through the entire range of yellows, ochres and reds, which makes this tree very spectacular. The male and female flowers are separate and grow as catkins, which are long hanging stems. The fruits are capsules that open when ripe to release seeds wrapped in a cottony material that helps them be dispersed by the wind. This fluff is often confused with pollen.
Although this species sometimes grows on riverbanks or in river valleys, it tends to be found within deciduous forests, provided that the soil is well developed and has sufficient moisture. It often forms small stands that arise from the resprouting of stumps, and it is considered a pioneer species in forest recolonisation. It grows from sea level up to 2000 m.
This tree occurs naturally across most of Europe and Asia, becoming scarcer toward the south and taking refuge in the mountains. It also appears in some places in the Moroccan Atlas mountains. On the Iberian Peninsula it is distributed across the northern half, Sistema Central and Sistema Ibérico ranges, certain areas in the Sil basin and is scattered throughout the mountains of Cuenca and Guadalajara.