THE ELM. 329 



also in Ireland, rarer in Scotland. Introduced into Britain, 

 where it does not, as a rule, bear fertile seed. 



Wych Elm. — Europe and Siberia. Indigenous in Britain, 

 going north to Sutherland, also in Ireland. Ascends to 1,300 

 feet in Yorkshire. 



r. LomlUij. 



Climate. — Elm requires a mild climate, but is not sensitive 

 to late frost. It is a light demanding tree, but less so than 

 oak and ash. It is only fairly storm firm, and the branches 

 of old trees are easily broken. 



Soil. — Elm demands a deep, fairl}' porous, moist and fertile 

 soil to do well ; hence it is mostly found on alluvial soils in 

 low lands and valleys. The wych elm is somewhat less 

 exacting than the common elm. 



(]. Shnpr anil IkTelopinenf. 



The elm divides into branches at about half its height. 

 The crown of the common elm is narrow and tends upwards ; 

 the wych elm has a broader crown. The root system consists 

 of a tap-root with numerous side roots ; at an advanced age 

 the system becomes somewhat more shallow. It grows quicker 

 than oak, but rather slower than ash, and reaches an ultimate 

 height of about 110 feet ; the common elm under specially 

 favourable conditions up to 125 feet. It attains a consider- 

 able diameter.* It is a long lived tree, reaching an age of 

 500 or even more years. 



('. Reprodurtive Power. 



The elm commences producing seed plentifully at the age of 

 about 40 years. The crops are heavy and occur about every 

 2 or 3 years ; in Britain the seed of the common elm very 

 rarely ripens. On the whole the reproductive power by seed 

 is great. Both elms have a great reproductive power from 

 the stool, there being stool shoots and suckers ; they also 



* The author has seen, at Schimsheim, in Ehenish Hessia. a cuniiiiou ehii tree 

 of fourteen feet diameter measured at three feet from the ground. 



