358 TRANSACTIONS OF ROYAL SCOTTISFI ARBORICULTURAL SOCIETY. 



again, what is to be said of the crop of wild hyacinth, etc. 1 Is, 

 then, the rotation of crops, so much insisted upon, a mistake 1 I 

 cannot answer, but only point oiit the fact that a piece of land 

 will pi'oduce year after year 4 tons per acre of the same crop, 

 while a similar piece only produces 2 tons of different crops, and 

 the former jiiece of land remains richer than the latter. 



The Sweet or Spanish Chestnut {Castanea vesca). — This noble 

 tree is not indigenous. It is, however, plentiful in the county, 

 and is naturalised, reproducing itself freely. While the oak and 

 the beech (especially the former) are attacked by catei'pillars, 

 aphis, and diffei'ent insects, producing galls and other excrescences, 

 the chestnut, so far as I have observed, is exempt from insect 

 pests. This immimity, and the value of the small-wood and 

 timber, while it is one of our fastest-growing deciduous trees (the 

 poplars and willows excepted), all combine to make it one of the 

 most valuable trees for planting. This seems to have been gene- 

 rally appreciated, for it has been extensively planted, and there 

 are now many plantations of useful timber trees and considerable 

 breadths of coppice. The trees are not of large dimensions, the 

 largest being in North Stoneham Park, with a girth of 16 feet 

 y inches. There are many girthing from 8 to 1 feet. 



The Hornbeam {Carpinus Betulus). — This tree is admitted into 

 the British flora, but is not common in Hampshire, and I am 

 not aware that it rejiroduces itself; for I have not found a single 

 " self-comer," and would therefore pronounce it not to be a native. 



Ulmace^. — The Elms have given rise to considerable discussion 

 amongst botanists as to the several species or varieties found wild 

 in Britain, and in consequence it is difficult to pronounce which 

 are natives, as all the species are trees of semi-cultivation, and 

 occur usually where the soil has been disturbed. 



The Common Elm [Ulmus camjyestrifi), the most majestic of all 

 the species, is common, occurring mostly in hedgerows, clumps, 

 and avenues. For the last it has a fine effect, but it cannot be 

 recommended for the purpose on account of its dangerous peculi- 

 arity, that without warning a large bough may snap and fall with 

 serious consequences. Several instances have occurred of persons 

 being killed from this cause. A fine avenue, the glory of South- 

 ampton thirty years ago, is now almost gone ; only a tree here 

 and there remains to show the ancient grandeur. Various theories 

 have been started as to the cause of this destruction, but no 

 satisfactory cause has been assigned. The Corporation of South- 



