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PRACTICE OF GARDENING. 



Part III. 



424 



and variegated caterpillars. These insects devour the leaves and eat deeply into the 

 fruit when grown to a good size ; so that it perishes and drops off* the trees. The shelters 

 are likewise very prejudicial to both fruit and branches, by depriving them of the descend- 

 ing dews, from which they imbibe great nourishment. Large pillars or piers have almost 

 the same ill effects ; besides, they shade the rays of the sun from the trees part of the day, 

 more or less, in proportion to their size. Though walls built with curves have, in calm 

 seasons, the benefit of more heat than others ; yet, in windy weather, the winds from 

 some point or other rebounding from side to side, break and destroy the tender branches 

 and blossoms of trees, whereby they are much more injured than the heat reflected from 

 one wall to the other can be of advantage to them. I have found by experience, that 

 walls built straight and upon arches, as mentioned before, are preferable to all others, 

 having a coping which projects about two inches to shoot off the rain, in order to preserve 

 the wall." (TV. on Fruit Trees, p. 40.) 



2451. With respect to the con- 

 struction ofivallsfor kitchen-gardens, 

 the common upright, straight wall 

 is now generally preferred to the 

 sloping, angular, or curved walls, 

 tried in several places about a cen- 

 tury ago, and criticised by Justice, 

 Miller, Switzer, and other authors 

 of that day. There may occur cases, 

 however, in which these uncommon 

 forms, and others which we have no- 

 ticed (1556 to 157 5.), may be adopted 

 with propriety. A very good applica- 

 tion of the angular wall, when formed 

 of boards, may be made in the case 

 of a circular garden. (Jig. 424. ) At 

 each angle (a, b) a light cast-iron 

 post with grooves is to be inserted 

 in the ground ; and in these grooves, 

 the ends of the boards, say in six or 

 eight feet lengths, are to be inserted, 

 and left without any fastening. If 

 they shrink during summer, being loose, they will only drop a little, but never show any 

 crevice ; and, in order to let the trees be fully exposed to the weather in winter, or to 

 paint, repair, or renew the boards, all or any part of the latter may easily be 

 taken out, leaving the cast-iron props in the grounds, and the trees as entirely detached 

 as if they were standards or border bushes (d). In this way, a large surface of cheap 

 and neat walling might be obtained in very little space, and on the whole an agreeable 

 effect produced. A walk, shrubbery and hedge (c) may surround the whole. 



2452. Fruit-walls, according to Hitt, should be founded on piers, " placing them at such 

 distances as to admit one tree of the sort proper for the aspect between, and forming them 

 of dimensions suitable to the size of the walls, and the nature of the foundations. The 

 advantages he states to be a saving of material and intended pasturage for the root. If, 

 however, the wall is to be planted with fruit-trees on both sides, the latter advantage is 

 imaginary ; and, indeed, the construction might often prove injurious by admitting the 

 hardy roots of trees, fit for a northern exposure, to intermix with the more delicate ones 

 of such as are planted on a south aspect. Justice, having disapproved of curved and 

 angular walls, says, " and as to the other methods of arching walls at their bottoms, that 

 is still worse ; for when the roots go out at the back sides of the walls at their freedom, 

 they draw all the rancid juices from the earths at the backs of the walls : in consequence 

 of which, the fruit infallibly falls off, after it has acquired its magnitude, &c." (Brit. 

 Gard. Direct, p. 5.) A late writer, J. Robertson (Hort. Trans, iv. p. 95.), recommends 

 such walls for peach-trees, but obviously on the supposition that no use is made either of 

 the north side of the wall, or north border, 



2453. The foundation of a garden-ivall, according to M'Phail, should be dug out no 

 deeper than the thickness of good earth on the surface, in order that as little wall may be 

 lost as possible. 



2454. Fruit-walls may be strengthened by piers, according to Forsyth, placed from forty 

 to sixty feet apart, and projecting half a brick beyond the wall. Such piers are now 

 made round, or rounded off, as the technical term is, which is more convenient for train- 

 ing trees. 



2455. Projecting stone buttresses are, in some places, set at intervals in the walls, 

 Neill informs us, in order to strengthen them, and break the force of the winds when 

 sweeping along. From the external angles of the walls of Dalmeny Park gardens, 





