484 ON USEFUL AND BOOK I. 



shade and drip of other trees ; and though it does not produce 

 large and thick masses of foliage, yet it shoots its twisted side- 

 branches horizontally across the naked stems of others — groups 

 with them, and destroys their formality. What adds greatly to 

 the effect of the Scotch elm, when in these circumstances, is a 

 species of black moss which infests its branches in almost every 

 situation, but here with great luxuriance favoured by the shade 

 and drip of the other trees. These remarks are strikingly 

 exemplified at Heckfall, near Rippon ; at Foxley ; Loudon 

 Castle, and many other places. 



9. The elder is propagated in a similar manner with the 

 willow, and with equal ease. It will thrive on the tops of moun- 

 tains *, or endure the most severe sea breeze ; as may be seen 

 all along the«east coast of Scotland. At the villages of North 

 Berwick and Preston Pans are excellent elder hedges, from four 

 to ten feet high, within a few feet of high-water mark. This is 

 a fact of great importance to those who have downs, or tracts of 

 barren sand near the sea; for, being in possession of this fact, 

 they may inclose and shelter them with little expense. Many 

 acres of this kind of ground exist along the coast in every quar- 



* There is a signal station on the summit of North Berwick Law, which is 800 

 feet above the level of the sea. The keeper, from the shelter of an elder hedge, has 

 made for himself a small but prolific kitchen garden, where before stood only a few 

 elder bushes, stunted and almost destroyed by sheep. 



