IN SCOTLAND.

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plants. The timber of this variety has not hitherto becomelarge enough in Scotland , to ascertain its value; but theexperience of several years has shewn, that this variety ispeculiarly liable to a species of blight, by which its ad-vancement is greatly deteriorated, and which, in some instan-ces, has threatened the destruction of entire plantations. Thisdisease consists of a white sweetish efflorescence, probablyproduced or occasioned by innumerable insects of the aphistribe, owing to which the tender shoots are stunted in theirgrowth, and die in the ensuing winter.

The hazel nut tree, or Corylus avellana , if planted thick,and judiciously pruned and interwoven, may be formed intoan efficient hedge. The shoots possess considerable strength,and are useful for making hoops, by their toughness and plia-bility ; not to mention the nuts produced upon the more ad-vanced branches.

The common medlar or Mespilus Germanica , the crab-treeor Pyrus maltts, the wild service-tree or Pyrus terminalis, andthe true service-tree or Pyrus domestica, may all be cultivatedoccasionally ns hedge plants, and a gap in a thorn-hedge mayoften be occupied with some of these, where young plants ofwhite-thorn would be oppressed. All the varieties of wild roseor briar may sometimes be useful to fill up gaps; but theyare liable to the objection already urged against the sweet-briar, as injurious to sheep.

The Sorbus aucuparia , rowen or roan tree, or mountainash, is one of the quickest growing trees known in Scotland ,especially for a dry barren soil. It grows naturally upright,with a tapering stem; but when pruned is apt to rise thickfrom the root in very numerous shoots, which soon fill up anopening or gap, but it does not generally thrive in such soils,when planted in close rows as a hedge *.

In gravelly soils, and for the purpose of close and effectualshelter at a small height, the beech-tree or Fagus sylvatica is

* Anderson's Essays on Agriculture.