THE ALDERS 91 



uriant of all our birch trees, and a worthy addition to any 

 park. 



THE ALDERS 



Closely related to the hornbeams and birches is a genus 

 of small water-loving trees that grow rapidly and serve 

 definite, special uses in the Old and New World. The 

 genus alnus includes tw^enty species, nine of which grow in 

 North America; six of these reach the height of trees. 



The Black Alder 



Alnus glutinosa, Gaertn. 



Of the alders, the black alders of Europe is the largest 

 and most important timber tree. Its range includes west- 

 ern Asia and northern xlfrica. It was introduced success- 

 fully into our Northeastern states in colonial times and has 

 become naturalized in many localities. These trees some- 

 times reach seventy feet in height and a trunk diameter 

 of three feet. Their dark green foliage, glutinous when 

 the leaves unfold in the spring, ranks these giant alders 

 among the beautiful and picturesque trees. 



The lumberman esteems alder wood only for special 

 purposes. It grows in w^ater and its wood resists decay bet- 

 ter than any other kind when saturated through indefinite 

 periods. In the old days it was the wood for the boat- 

 builder. The i)iles of the Rialto in Venice and along the 

 canals of Amsterdam and other Dutch cities are of black 

 alder. Water pipes and troughs, pumps, barrel staves, 

 kneading troughs, sabots and clogs were made of alder 

 wood. The bark and cones are rich in tannin and a vellow 



