The wrong rootstock was chosen for the cultivars.

The scion vigour was not integrated in the spacing decision.

Trees were planted closer than they should have been.

Ringing, Scoring and root pruning may be helpful in controlling vegetative growth in these types of plantings.

Bark Ringing

Bark ringing is a more drastic step than scoring which entails cutting out a ring of bark 1/8 in. (3mm) wide all round the trunk. This method is used to try to force fruit trees and some other woody plants to flower. A complete ring is cut around the trunk below the lowest branch and another ring is cut right below the first. The bark between the rings is removed and the scar should be covered with grafting wax.

Scoring and bark ringing breaks the flow of nutrients, photosynthates, and growth regulators between the tree canopy and its roots. The score will heal, but prior to healing it will reduce both the length and diameter of the new growth. Additionally, it will enhance fruit set and increase flower bud formation for the next season. Enhanced fruit set will also help reduce growth. However it has on occasion been noted that sensitivity to winter injury of the wood in the scored area has taken place.

Scoring

Scoring very simply, is the process of making a single cut with a knife (a linoleum knife works very well) completely around the trunk of the tree somewhere between the soil and the lowest scaffold branches.

This process is done when new growth is approximately 4 to 6 in. (10cm-15cm) in length, usually about 10 days after petal fall. More than one time around the tree provides no additional benefit. Scoring later in the season reduces the effectiveness, and likely will provide no benefit if done after June drop. Caution is advised when selecting trees to score. Weak or moderately vigorous trees may loose much more of their vigour by the scoring treatment, and this effect may last for several years. On vigorous trees, scoring may be performed in successive years, but careful assessment of the previous season's growth should be made each year prior to treatment.