BRITISH FOREST TREES 265 



other ; they are certainly classifiable as light-loving, if not 

 exactly light-demanding species. In their earlier stages of 

 growth they can bear, on sufficiently moist soil, the shade of 

 lofty standards for several years without suffering loss of 

 recuperative power when allowed to have a freer enjoyment 

 of sunshine and warmth. Their love of light is, how- 

 ever, unmistakable ; groups of pure elms do not main- 

 tain themselves long in full canopy, and, in coppices 

 especially, the necessity for a fuller measure of light and air 

 is soon noticeable. The crown of foliage is distinctly dense 

 in the English and Scots elms, but the shade cast by the 

 Cork elm is somewhat lighter. According to Ney, they bear 

 less shade than the beech and hornbeam, but more than 

 ash, maple, and sycamore ; they are certainly endowed with 

 a denser foliage than these latter species. 



Attainment of Maturity and Reproductive Capacity. From 

 about their thirtieth year onwards, elms produce seed almost 

 annually ; they flower in April, and the fruits ripen and fall 

 about the end of May or the beginning of June. Good seed- 

 years occur every two or three years ; but unless utilised at 

 once, the seed is apt to become easily heated and to lose its 

 germinative capacity rapidly, which even in fresh, good seed 

 averages only about forty to forty-five per cent. Owing to 

 the loss of germinable capacity, the seed cannot be kept over 

 winter till the following spring, though, as a sufficiency of seed 

 seldom fails in any year, this is of little importance. The 

 English elm, which makes greatest demands on warmth of 

 climate, does not bear seed in Scotland, and even in England, 

 is a very poor seed-producer ; but it compensates for this by 

 its capacity for throwing out stoles or root suckers, which 

 establish themselves, and are removable as single individuals. 

 The Scots elm throws out very few, if indeed any, suckers, 

 but produces good seed abundantly. The seed of these 

 two varieties is very much alike; in the English elm, how- 



