17»6 ARBORETUM AND FRUTICETUM. PART 111. 



The bark o( Q. Subcr furnishes suberine. the suberic acid, unci a product 

 bj tar more important than that of any species of the genus, cork ; a substance 

 which is not produced by any other tree whatever, in sufficient quantities to 

 be applied to any useful purpose. 



The leaves, the (lowers, and the fruit, according to Bosc, afford nourish- 

 ment to more than 800 species of insects, even in the neighbourhood of Paris; 

 and some of these insects are either valuable themselves in the arts, or they 

 are the cause oi' excrescences, such as oak galls, which are valuable. The 

 haves oi Q. eoccifera afford nourishment to the Coccus ilicis, a hemipterous 

 insect, which is used in medicine under the name of kermes, and has been 

 employed in dyeing scarlet, from the remotest antiquity, under the name of 

 scarlet grain. This insect is produced, ami cultivated for commerce, in the 

 south ot France, ami in various parts of the south of Europe, and of the East. 

 Oak galls, which are much in demand for the manufacture of ink and for dyeing 

 black, are produced on most of the deciduous European species, and are veiy 

 abundant on the section fidbur; but the galls of commerce are chiefly pro- 

 duced by the Q. infectoria, a native of Asia Minor and the adjoining countries. 

 All the smaller parts of oaks, such as the spray, buds, leaves, flowers, and 

 fruit, may be employed in tanning; and, accordingly, the cups, or calyxes, of 

 some species are in use for this purpose, more particularly those of the valonia 

 oak ( Q. yft'gilops), a native of the Archipelago. The leaves of the section 

 /lobur are used as a substitute for spent tanner's bark in hot-houses ; and 

 being slow in decomposition, are found to retain the heat for a longer period 

 than those of any other European trees. 



The acorns of all the species are edible ; and, in every country where the 

 oak abounds, they form the most important part of the food of wild quadru- 

 peds of the fructivorous or omnivorous kinds, and of some birds. The wild 

 animals most useful to man, which are nourished by them, both in Europe 

 and America, are the wild boar, the stag, and the goat. In Asia, pheasants 

 and pigeons, with other birds in a wild state, cat acorns, no less than wild qua- 

 drupeds. In North America, cows, horses, swine, bears, squirrels, pigeons, 

 and wild turkeys devour them. Among the domestic animals which eat and 

 thrive on acorns, the principal is the swine; but there are few animals and 

 birds, in a state of domestication, Bosc observes, that may not be made to 

 live and thrive on them, however unwilling they may be to touch them at 

 first. In the earlier ages, there can be no doubt that acorns, in the countries 

 where they were produced, were the food of man; and they are still, as we 

 have seen, eaten in some parts of the south of Europe, the north of Africa, 

 and the west of Asia. The kinds which produce the acorns most valued 

 lor eating are, Q, /'lex, Q. Jialluta, Q. gramuntia, and Q. JS'sculus. The degree 

 of bitterness in acorns, produced by the same species, varies exceedingly on 

 different trees ; and were any kind of oak to be introduced into orchards as a 

 fruit tree, it would be advisable to select only the best varieties of particular 

 species, and propagate these by grafting. There are even varieties of Q. 

 fidbur which produce acorns much less bitter than others; and we have 

 received some from a tree of this species, in the south of France, which ac- 

 cording to Dralet, are so sweet as to be eaten by the inhabitants. (See Rc- 

 ckerchei tur lei Chenet a a lands doux t p. 178.} 



The entire tree or shrub, in the case of every species of oak, may be con- 

 sidered as highly ornamental : the least so are the willow-leaved oaks, and 

 the most SO the lobed and deeply sinuated leaved kinds. The foliage, even, 

 of the lame -\>< cies, and more especially of the deciduous kinds, varies ex- 

 ( eedingly ; not only on different individuals, but on the same individual at 

 differ* Ol the war. In spring, the; leaves oi' many of the decidu- 



OUf kinds are small, delicate, and beautifully tinged with yellow and red j in 

 ■ummer, they are broad and green ; and in autumn, coriaceous, and of a 

 I brown, scarlet, or blood-red colour. Nothing cat) be more remarkable 

 than the variation in the forms of the leaves, in the same individual, in some 

 of the American pecie ; those of the tree, when young, being sometimes 



