The dying back of a tree at the top indicates that the trouble is in the roots, and it is usually due to standing water in the soil, resulting either from excessive application of water or because the soil is too retentive to distribute an amount of water which might not be excessive on a lighter soil which would allow of its freer movement. Dig down near the tree and see if you have not a muddy subsoil. The same trouble would result if the subsoil is too dry, and that also you can ascertain by digging. If you find moisture ample, and yet not excessive, the injury to the root might be due to the presence of alkali, or to excessive use of fertilizers. The cause of the trouble has to be determined by local examination and cannot be prescribed on the basis of a description of the plant. It cannot be cured by spraying unless specific parasite is found which can be killed by it. Young Trees Dropping Fruit. I have a few citrus fruit trees about three years old. They have made a good growth and are between seven and eight feet high with a good shaped top or head. I did not expect any fruit last year and did not have any. This spring they blossomed irregularly at blooming time, but quite an amount of fruit set and grew as large as marbles, some of it the size of a walnut, but lately it has about all fallen off the trees. There is always more or less dropping from fruit trees. Some years large numbers of oranges drop. There may be many causes, and the trouble has thus far not been found preventable. When the foliage is good and the growth satisfactory, the young tree is certainly not in need of anything. It is rather more likely that fruit is dropped by the young trees owing to their excessive vegetative vigor, for it is a general fact that fruit trees which are growing very fast are less certain in fruit-setting. It is, of course, possible that you have been forcing such action by too free use of water. You will do well to let your trees go along so long as they appear thrifty and satisfactory, and expect better fruiting when they become older. Orange Training. Is not a single leader in an orange tree more desirable than the much-forked tree so commonly seen! Can a single-leader tree be made from the nursery trees which have already formed their heads, by cutting off the heads below so that only a straight stick without any branches is left? An orange tree with a central leader would not be at all satisfactory if it were carried very high. Of course, a central stem can be to advantage taken higher than it is often done, but we would not think of growing an orange tree with a central stem to the apex. The laterals would droop, crowd down upon each other badly, open the center to sunburn, and encourage also a growth of central suckers and occasion an amount of pruning altogether beyond what is necessary with a properly branched tree without a central stem. Curing Citron.