In the absence of suitable approved chemicals for thinning fruitlets on apple trees they can only be thinned by hand. This is a very expensive procedure and, with pruning and harvesting, represents one of the major costs in apple production.
- Attempts have been made to thin fruitlets of some crops (e.g. plums) using mechanical aids, but little or no work has focused on this strategy, which relies on tree shaking or combing devices, for apple.
- Fruitlet drop may also be induced using other techniques. One of these, recently tested in the USA, is to induce thinning by shading trees.