The Elder I've used is Box Elder, which is a relation to the Maple tree.  I've only got it because one was taken down and the wood was available (I like to try different things!)

 

The wood is very pale and the trees don't live for that long (well 60-100 years).  But the patterning is unique.  I think it looks like the surface of the moon, with crater like rings.

 

Eco wise, very good again as it's fast growing it eats up the CO2.