462 Diseases in Fruit Trees, 



and healthy channels, forces out at the bases of these cankered 

 shoots others that, in summer, are strong and luxuriant, but 

 which again, in like manner, in the following winter, canker and 

 die. The juices of the plants, from not being properly elaborated, 

 become diseased, and food fit only to nourish those animals that 

 seem created to feast on decay ; while the whole tree becomes a 

 confused mass of dead and dying branches. From close obser- 

 vation of the effect of these last two or three favourable warm 

 summers, I cannot think this altogether produced by the climate, 

 but that it arises from some inexplicable effect proceeding from 

 the variation of soils ; for, in situations which, as far as regards 

 climate, are more moist and cold than any in this part of 

 England, I have seen sorts that canker here flourish without 

 spot or blemish. I am, however, almost equally at a loss when 

 I impute it to unfavourable soils, as we have here a most re- 

 markable variation in soils, from a dark strong clay, to a rich 

 friable stratum of loam, 10 ft. in thickness, resting on a sub- 

 stratum of dry sand ; apparently the most favourable combination 

 possible for fruit trees : and yet, even here, some of the old 

 varieties of pears, such as crassane, brown beurre, Colmar, &c., 

 in five years from the graft, canker, and seldom show a fruit- 

 spur ; but graft these cankered trees with new and hardy sorts, 

 and fruitfulness and health will immediately take the places of 

 disease and death. 



The grand point in fruit culture is, to have sorts producing 

 shoots that do not die at the extremities ; they will then furnish 

 leaves enough for all the offices of nature. This is no new 

 doctrine, as we have been often told the effect of fruit trees in 

 producing tender shoots ; but the cause is still worth enquiring 

 into: for I well know that it has often, and with apparent justice, 

 been attributed to cold seasons and wet soils ; though I know 

 equally well that it occurs in seasons and soils quite the reverse. 

 How, then, shall we account for the circulating fluids being so 

 inimical to health in some varieties of fruit, and not in others ? 1 

 can also assert, from experience, that sorts of fruit recently ob- 

 tained from seeds are not by any means all exempt from canker ; 

 for several seedling apples and pears (perhaps the average may 

 be one in a hundred) I have found equally or even more tender 

 than our old varieties : I have grafted these tender striplings 

 with robust sorts, and have at once changed their nature. This 

 is interesting, and, to a reflective mind (it must not be over- 

 burthened with the cares of a nursery), offers a vast field of 

 enquiry. I must conclude with one recommendation : let the 

 fruit amateur or orchardist, the instant he finds a fruit tree making 

 shoots it cannot support, either root it up, and plant it afresh ; or 

 graft it with some robust and productive variety. 

 Sawbridgeworth Nursery, Herts, April 20. 1836. 



