160 and 164). 'Peregrine' (white fleshed, ripening in mid August, is a very reliable cultivar of high quality when trained as a fan. So also are 'Duke of York' (mid-July), 'Hale's Early' (late July) and 'Royal George' (early September), all white fleshed. Ripening under glass would be advanced by three weeks or so. Diseases PEACH LEAF CURL A serious disease for trees in the open and requires a regular spray programme of a copper fungicide applied as soon as buds show movement (this can be late January-early February in some localities) and repeated two weeks later. BROWN ROT Can affect fruit badly on trees in the open and all diseased specimens should be removed and burnt. A disorder SPLIT STONE As the name implies, a disorder that fractures the stone on the ripening fruit. The cause of this is not known although dryness at the roots is possibly a contributory factor.cooler areas. Apart from the need for extra warmth, the requirements of site and soil are much as for apples (see p.233). The use of warm walls for training choice cultivars should be considered. Too alkaline soils should be avoided, and windy sites will quickly result in blackening and dessication of the tender young foliage. Rootstocks Quince A produces good cropping trees of moderate size, while Quince ะก gives rather smaller trees that are quick to crop. In propagation the problem of incompatability of some cultivars, e.g., 'Marie Louise', 'Packham's Triumph' and 'Williams' Bon Chretien', with quince can be overcome by introducing a small piece of wood from a compatible cultivar like 'Beurre Hardy' between the two (double-working as it is known). Tree Forms The cordon, dwarf pyramid, bush and fan are ideal for pears and the espalier can also be successful. For details and planting distances see Apples p.233. Pollination Like apples, all pears should be treated as being self-sterile so the careful selection of combinations of cultivars for planting together is very important. Expert advice should be sought. Fruit thinning is seldom necessary. Recommended Cultivars The fruit of the two culinary cultivars needs to be sliced and cooked slowly for seven to eight hours when it will make a very pleasing, and different dish. Neither cultivar can be used as a dessert pear. Dessert 'Marie Louise' (10-11) + 'Williams'Bon Chretien'(9) 'Emile d'Heyst' (10-11) 'Fondante d'Automne' (9) 'Doyenne du Cornice' (11-12) * 'Onward' (9-10) 'Josephine de Marines' (12-1) 'Gorham' (9-10) Culinary 'Bristol Cross' (10) 'Bellissime d'Hiver' (12-3) 'Conference' (10) 'Catillac' (12-3) Key: + Freezes well The figures in brackets denote * New introduction months of ripening Nutrition Basically this is as for apples but with rather more nitrogen being given, especially in grass. Lime-induced chlorosis can also be a problem (see p.232) Planting and Support See Apples . Pruning Again, this is generally as for apples. Do not over-prune before cropping commences on vigorous trees like 'Doyenne du Cornice'.