Trees thus trained may be planted thick enough to allow four hundred to stand on an acre, and will bear an abundance of the finest fruit, and all low enough to be easily picked. This method of training is much better than allowing the tree to shoot out on all sides from the ground: in that case, the branches are apt to split down and perish. This system of heading-in freely every year, preserves the life and health of the tree remarkably. Many of the finest peach-trees in France are from thirty to sixty years old, and some a hundred. We may, in this country, have peach-trees live fifty years, in the most healthy bearing condition. By trimming in this way, and carrying out fully this system, some have thrifty-looking peach-trees, more than a foot in diameter, bearing the very best of fruit. It is sheer neglect that causes our peach-orchards to perish after having borne from three to six years. Let every man who plants a peach-tree remember, that this system of training will make his tree live long, be healthy, grow vigorously, and bear abundantly. _Diseases_ of peach-trees have been a matter of much speculation. The result is, that the hope of the peach-grower is mainly in preventives. _The Yellows_ is usually regarded as a disease. Imagination has invented many causes of this evil. Some suppose it to be produced by small insects; others that it is in the seed. Again, it is ascribed to the atmosphere. It has been supposed to be propagated in many ways--by trimming a healthy tree with a knife that had been used on a diseased one; by contagion in the atmostphere, as the measles or small-pox; by impregnation from the pollen, through the agency of winds or bees; by the migration of small insects; or by planting diseased seeds, or budding from diseased trees. This great diversity of opinion leaves room to doubt whether the yellows in peach-trees be a disease at all, or only a symptom of general decay. The symptoms, as given in all the fruit-books, are only such as would be natural from decay and death of the tree, from any cause whatever. This may result from neglect to supply the soil with suitable manures, and to trim trees properly, and especially from over-bearing. This view of the case is more probable, from the fact that none pretend to have found a remedy. All advise to remove the tree thus affected at once, root and branch. We have seen the following treatment of such trees tried with marked success. Cut off a large share of the top, as when you would renew an old, neglected tree; lay the large roots bare, making a sort of basin around the body of the tree, and pour in three pailfuls of _boiling_ water: the tree will start anew and do well. This is an excellent application to an old, failing peach-tree. The sure preventive of the yellows is, planting seeds of healthy trees, budding from the most vigorous, heading-in well, supplying appropriate manures, and general good cultivation.