558 PROTECTION AGAINST HAIL. 



may be seriously injured ; the birch owing to its elastic shoots 

 and leathery bark does not suffer much from hail. 



Young plants 1 to 15 years old are most endangered, year- 

 lings being often destroyed by a hailstorm ; and sowings, 

 especially when on a large scale, suffer more than plantations. 

 Poles 15 to 30 years old suffer less than younger plants, while 

 serious damage is rarely done to trees over 30 years old. The 

 later in the spring the hail occurs, the greater is the damage, 

 especially to smooth-barked, weakly plants. 



Oak-coppice for bark and osier-beds may suffer severely 

 from hail. The damaged oak shoots are difficult to peel, and 

 the osier wands break at the injured points. Even coppice- 

 with-standards may often suffer severely. In high forest, 

 open woods suffer more than dense woods, and isolated 

 trees and those along the borders of the forest suffer most. 

 Westerly, south-westerly and north-westerly aspects are chiefly 

 threatened, as hail usually falls with a west or south-west 

 wind. The stronger the wind, the greater the damage. 



2. Prevalence of Hailstorms. 



Hailstorms are not very common in Europe, they occur 

 only in late spring or summer and generally during the day- 

 time. They are very severe in Northern India, occurring 

 generally during April and May, and the stones are then 

 frequently as large as walnuts, and batter stucco buildings as 

 if they had been subjected to a volley of musketry and even 

 penetrate corrugated iron roofs. Such hailstorms may com- 

 pletely strip the young shoots from trees and tea-bushes, in 

 the latter case causing damage which may be estimated at 

 thousands of pounds for a tea district. 



In Germany there are, on the average, only about five hail- 

 storms a year, but on the west coast of Europe there are 

 about fifteen. These are sometimes very local, extending 

 only over small areas. Thus, in Cambridgeshire, within fifteen 

 miles round Chatteris, one shilling per acre insurance for 

 agricultural crops against hail is charged ; outside this zone, 

 sixpence per acre. 



Hailstorms are very prevalent in Wiirttemberg, where 

 thousands of acres of cultivated land are annually laid waste 



