BOOK IV. INDUCING FRUITFULNESS. 415 



tap to drive it a little, which loosening it from its rust, makes it come out easier, and so 

 saves a wall from large holes, which is a material thing. (Introd. to Card. ) 



2155. Herbaceous training is performed by means of poles, rods, branches, and pegs. 

 Plants that twine and grow high are furnished with high poles, on which to twine them- 

 selves, as the tamis, convolvulus, &c. Plants with tendrils, as the pea, the bryonia, &c. 

 are furnished with branches or spray, through which the plant springing up attaches itself 

 by its tendrils, and is thus better exposed to the sun and air, and not so liable to rot as 

 when it lies on the ground. Props or poles are used for supporting and leading upright, 

 tall, slender, growing plants, as the dahlia, tree-lupin, and the like. Creeping and trail- 

 ing plants, as the melon, gourd, &c. are generally trained in the stellate manner on the 

 ground by means of pegs ; sometimes also on walls and trellises. 



SUBSECT. 5. Blanching. 



2156. Blanching is an operation of culture performed by earthing the stems of plants, 

 by tying up their leaves, or by covering them with utensils from the light. 



2157. Blanching by earthing is performed on the celery, chardoon, asparagus, &c. In 

 the case of annuals the earth is generally drawn up so as to press on the leaves of the plant 

 as it advances in growth ; in the case of perennials a covering of loose earth is generally 

 placed over them before the growing season, through which the stalks shoot up, and 

 are blanched. 



2158. Blanching by tying together the leaves is sometimes performed on lettuce, cabbage, 

 endive, &c. The plant being nearly in its most leafy state, the head or fasciculus of 

 leaves are gathered together, and tied up with bass ribands. By this operation two effects 

 are produced : the inner leaves as they grow, being excluded from the light, are blanched ; 

 and being compressed in proportion to the growth, which takes place after tying up the 

 head, the fasciculus becomes both tender and solid. 



2159. Blanching by overlaying is merely the laying down of tiles, slates, pieces of boards, 

 &c. on endive and other salading, when nearly full grown, and of which, being thus ex- 

 cluded from the sun, the future growth is colorless. Covering by the following mode is 

 preferable. 



2160. Blanching by covering with utensils is a recent invention applied to sea-kale, 

 rhubarb, asparagus, &c. and consists in placing over them the utensils already described 

 as appropriated to this purpose. (1427.) 



SECT. IV. Operations for inducing a State of Fruitfulness in barren and unblossoming 



Trees and Plants. 



2161. Various means have been tried to induce fruitfulness with different degrees of 

 success. Almost every description of fruit-tree, if planted in a thin stratum of rich loam 

 on a dry and impervious sub-soil, will come into bearing in regular course, according to 

 its nature ; but it too frequently happens that the stratum of soil is too deep, or the roots 

 penetrate into the sub-soil, or by some means, not always obvious, acquire the power of 

 throwing much superfluous sap into the tree, which spends itself in leaves and branches, 

 instead of blossoms. Similar circumstances produce similar effects in ornamental trees 

 and shrubs, whether in the open air or in artificial climates. Attempts are known to have 

 been made for upwards of a century and a half, to cause such trees to produce blossoms, 

 attended with different degrees of success ; but the practice was carried on empirically, 

 without any knowledge of the reason or principle which operated in producing the desired 

 end, till its true rationale was given by Du Hamel, in his Physique des Arbres, 1 758. 



2162. Laying bare the roots of trees is mentioned by Evelyn as conducive to fertility. 

 Transplanting the tree frequently", by Van Osten. Boring a hole, and driving in an 

 oaken plug is mentioned by the same author as the "old way." Every one must 

 have observed that trees partially blown out of the ground, or with the earth washed 

 or otherwise removed from their roots in banks or river-sides, or with their trunks or 

 roots broken, bent, or mutilated in any way, are always more fruitful than others ; and 

 this, we conceive, has suggested the various modes of artificial mutilation. Mutilation, 

 both in plants and animals, is attended by a sort of maturity ; and maturity in all living 

 things is the period of reproduction. 



2163. Cutting the roots of trees is an old practice, generally performed in winter or 

 spring, but recently by Beattie, gardener at Scone, in midsummer. " In the begin- 

 ning of July 1811, I had a border on the south wall, of 400 feet long, trenched to the 

 depth of from two and a half to three feet; in doing this, I had the opportunity 

 of cutting the roots of all the trees, as the work went on, which I did so completely, 

 that they in a manner hung by the nails and shreds, with a ball of earth of about two 

 feet from the stem of the tree. As cutting the roots of fruit-trees has a tendency to 

 make them fruitful, that may possibly proceed from the small quantity of fibrous roots 

 produced by the operation." Beattie says, he acted on the principle of depriving the tree 

 of the means of containing such a great quantity of sap, thereby preventing it from 



