I have 10 cordon apple trees, most of which are at least 10 years old, thus well established. Few fruited this year but it seems that the ones with the most fruit are dying. A Rubinette has apparently died; all the leaves turned brown. The other one in trouble, a Bramley's Seedling,--at the other end of the rowo-- is loaded with apples but the leaves, especially nearest the fruit, are brown. It looks terrible. Has the same problem hit these 2, at opposite ends? It can't be lack of water since none of the others are affected. Any ideas?