Showing posts with label Alnus glutinosa. Show all posts
Showing posts with label Alnus glutinosa. Show all posts

Wednesday, December 26, 2012

Alder's Hidden Charms
























There isn't a lot of colour in the countryside at the moment but this brightly coloured alder timber, in a small local wood where the owner had been pruning and thinning trees, livened up a dull, grey day. Common alder is a somewhat sombre tree, so it always comes as a surprise the see the bright orange pigmentation that develops in the newly-cut wood. It looks like this particular tree was about thirty years old.



































When you look a little close the colour becomes even more striking because the inner layers of bark have a distinct violet hue, similar to the colour of the tree's bud scales when they begin to swell in spring.



Alder timber isn't of much use when dry, other than for making charcoal that was particularly valued for the production of gunpowder. It's a different story, though, if the wood is kept permanently wet because then it is long-lasting. It was the favourite material for making soles of clogs, both because of its toughness when wet and because of its resistance to splitting when small nails are driven in around the edge of the wooden sole. It also made excellent piles for driving into the ground for bridge foundations.

Friday, December 4, 2009

A Tree-spotter's Guide to Buds: part 2


White poplar Populus alba winter buds are covered in a dense felt of fine white hairs that, from a distance, make the twig look as though it's been dipped in white emulsion. The white hairs cover the underside of the leaves too, which flash green and white when they flutter in the breeze in spring and yellow and white when they change colour in autumn.


Alder Alnus glutinosa buds have this beautiful violet-purple sheen that intensies in spring, as the buds begin to swell


Common lime Tilia x europaea buds, which are rounded and have few bud scales, develop a deep crimson hue when they're exposed to sunlight, but on their shaded underside (right hand twig above) they remain green. The purple pigment is produced in response to bright sunlight.


Sweet chestnut Castanea sativa buds are also tinged red but the twigs are chestnut brown. Notice how the buds below the terminal bud sit on a little shelf.


... and this is rowan Sorbus aucuparia, possibly the least attractive buds amongst native species, whose hairy, pointed buds lack shiny scales.



For more posts on tree ID click here