Tree Training Tips - “Keeping your trees in the zone”
A young peach tree is generally very vigorous and will develop numerous fruiting limbs. However, as peach trees mature, it is common to see very little new fruiting wood develop on older limbs. This problem is the result of growing structural wood adjacent to a fruiting wood zone. The large side secondary structural limbs will eventually inhibit the emergence of new fruiting wood on the proximal (toward scaffold) side in the zone marked with the white bar.
The solution in this case is to remove or severely stub the large side branch, thereby allowing the primary structural limb to continue generating new fruiting wood in future years. This leads to the broader question: “where are the fruiting zones on the tree?” The picture on the right shows a situation where larger limbs were kept on a scaffold. If the large limb on the upper left is allowed to remain, the scaffold will lose its ability to generate new fruiting wood and will become a purely structural limb. This same situation is starting to occur at the very top of the tree. The relatively large side limbs at the very top are beginning to have inhibitory effects below them. Thus, the fruiting zone is shifting to the top of the tree.
Again, the solution is to remove or stub limbs (see below) that are shutting off fruiting zones you want to retain. This general concept of fruit zones applies to all the various tree designs such as open center, freestanding Y, quad V, etc. Each design has its target number of primary limbs (uprights) arising from the trunk. Regardless of the design, the goal is to maintain the fruiting zones on these “uprights”.
Oversized limbs eventually inhibits the fruiting zone of primary limbs unless removed.