1'REFACE. 



" The limits within which experiments of this kind must be confined are, how- 

 ever; narrow. It seems that cross fertilization will not take place at all, or very 

 rarely, between different species, unless these species are nearly related to each 

 other; and that the offspring of the two distinct species is itself sterile, or if it 

 possesses the power of multiplying itself by seed, its progeny returns back to the 

 state of one or other of its parents. Hence it seldom or never has happened 

 that domesticated fruits have had such an origin. We have no varieties raised 

 between the Apple and the Pear, or the duince and the latter, or the Plum and 

 Cherry, or the Gooseberry and the Currant. On the other hand, new varieties 

 obtained by the intermixture of two pre-existing varieties are not less prolific, 

 but, on the contrary, often more so than cither of their parents ; witness the nu- 

 merous sorts of Flemish Pears which have been raised by cross fertilization from 

 bad bearers, within the last twenty years, and which are the most prolific fruit 

 trees with which gardeners are acquainted ; witness also Mr. Knight's Cherries, 

 raised between the May Duke and the Graffion, and the Coe's Plum already 

 mentioned. 



" It is, therefore, to the intermixture of the most valuable existing varieties of 

 fruit that gardeners should trust for the amelioration of their stock. By this 

 operation the pears that are in eating in the spring have been rendered as deli- 

 cious and as fertile as those of the autumn ; and there is no apparent reason why 

 those very early, but worthless sorts, such as the Muscat Robert, which usher in 

 the season of Pears, should riot be brought to a similar state of perfection. 



" There is no kind of fruit, however delicious, that may not be deteriorated, or 

 however worthless, that may riot be ameliorated, by particular modes of manage- 

 ment; so that after a given variety shall have been created, its merits may still be 

 either elicited or destroyed by the cultivator. In this place those practices only 

 need be considered that tend to improvement. 



" Some fruits of excellent quality are bad bearers : this defect is remedied by a 

 variety of different methods, such as, 1. By ringing the bark; 2. By bending 

 branches downwards; 3. By training ; and, 4. By the use of different kinds of 

 stocks. All these practices are intended to produce exactly the same effect by dif- 

 ferent ways. Physiologists know that whatever tends to cause a rapid diffusion 

 of the sap and secretions of any plant, causes also the formation of leaf buds in- 

 stead of flower buds; and that whatever, on the contrary, tends to cause an ac- 

 cumulation of sap and secretions, has the effect of producing flower buds in 

 abundance. This circumstance, which at first sight seems to be difficult to 

 account for physiogically, is no doubt to be explained by the difference between 

 leaf buds and flower buds themselves. In a leaf bud, all the appendages or leaves, 

 are in a high state of development, and the central part or axis, around which 

 they are arranged, has a tendency to extend itself in the form of a branch as soon 

 as the necessary stimulus has been communicated to the system by the light and 

 warmth of spring. In a flower bud, the appendages or leaves are in that imper- 

 fectly formed, contracted state, which we name calyx, corolla, stamens, and pistilla ; 

 and the central part around which they are arranged, has itself no tendency to elon- 

 gate under the influence of the usual stimulants. Hence, a flower bud, or flower, 

 is nothing but a contracted branch ; as is proved by the occasional elongation of 

 the axis in flowers that expand during unusually hot damp weather late in (he 

 spring, becoming branches, bearing sepals and petals instead of leaves. It is, 

 therefore, easily to be understood why, so long as all the motions in the fluids and 

 secretions of a tree go on rapidly, with vigor, and without interruption, only rudi- 

 ments of branches (or leaf buds) should be formed ; and why, on the other hand, 

 when the former become languid, and the parts are formed slowly, bodies of a 

 contracted nature, with no disposition to extension, (or flower buds) should appear. 

 " It will be found that the success of the practices above enumerated, to which 

 the gardener has recourse in order to increase the fertility of his fruit trees, is to 

 be explained by what has just been said. In ringing fruit trees, a cylinder of 

 bark is cut from the branch, by which means the return of the elaborated juices 

 from the leaves down the bark is cut off, and all that would have been expended 

 below the annular incision is confined to the branch above it. This produces an 

 accumulation of proper juice; and flower buds, or fertility, are the result. But 

 there is a defect in this practice, to which want of success in many cases is no 

 doubt to be attributed. Although the returning fluid is found to accumulate 

 Above the annular incision, yet the ascending sap flows along the alburnum into 



