Trembling Aspen

	The Aspen Poplar or Trembling Aspen is a very common tree found in mixed woodland, with Birch, and the edge of farm land. It is fast growing and is harvested for its light coloured wood.
	The leaves are heart shaped and light yellow/green in colour. They appear after the catkins in May.
	The leaves posses long stalks so that when the wind blows, they tremble, hence the name trembling aspen.
	The bark of the aspen is light in colour, smooth and thin. As trees mature the bark may become dark grey furrowed and thick.
The flowers are found in the soft, drooping, caterpillar-like ‘catkins’ which hang from the twigs.	Male and female catkins are found on different trees. The female catkins are vase-shaped and stay green until the sticky seeds are released .
	Male catkins emerge in late winter and lengthen in spring when red/pink pollen sacs can be observed. After they have released their pollen into the air the catkin dries up and falls off.

•Choose a male tree in an area that you visit regularly

•Avoid trees which are within 10 metres of any buildings.

•Tag your chosen tree using a ribbon or other marker

What to record

•Record when the catkins on your chosen tree first start shedding pollen (in three different places on the tree)

•Make a note of when 50% of the male catkins have lengthened and shed pollen

•Finally, record when the first leaves push out of their buds and unfold completely (in three places on the tree)

Back to list of species

Back to Homepage