1120. To increase the Growth in Trees.—It may be depended upon as a fact, that by occasionally washing the stems of trees, their growth will be greatly increased; for several recent experiments have proved, that all the ingredients of vegetation united, which are received from the roots, stem, branches, and leaves of a mossy and dirty tree, do not produce half the increase either in wood or fruit, that another gains whose stem is clean. It is clearly obvious, that proper nourishment cannot be received from rain, for the dirty stem will retain the moisture longer than when clean; and the moss and dirt will absorb the finest parts of the dew, and likewise act as a screen, by depriving the tree of that share of sun and air which it requires.
A common scrubbing-brush and clean water is all that is necessary, only care must be observed not to injure the bark.
1121. To prevent Hares and Rabbits from Barking young Plantations.—Hares, rabbits, and rats, have a natural antipathy to tar; but tar, though fluid, contracts, when exposed to the sun and air for a time, a great dryness and a very binding quality; and if applied to trees in its natural state, will occasion them to be bark-bound. To remove this difficulty, tar is of so strong a savor, that a small quantity mixed with other things, in their nature open and loose, will give the whole mixture such a degree of its own taste and smell, as will prevent hares, &c., touching what it is applied to.
Take any quantity of tar, and six or seven times as much grease, stirring and mixing them well together; with this composition brush the stems of young trees, as high as hares, &c., can reach; and it will effectually prevent their being barked.
1122. Bad effects of Iron Nails, &c., on Fruit-trees, or mischievous effects of Iron Nails, in conjunction with Branches of Fruit-trees.—It often happens that some of the limbs of fruit-trees, trained against a wall, are blighted and die, while others remain in a healthy and flourishing state. This has been hitherto erroneously attributed to the effects of lightning; but, from closer observation, and from several experiments, it has been found to arise from the corroding effects of the rust of the nails and cramps with which trees in this situation are fastened. To avoid this inconvenience, therefore, it requires only to be careful in preventing the iron from coming in contact with the bark of the trees.