Answer: Home fruit tree growers are in a difficult position because many fruits, such as apples, demand a heavy spray schedule in order to achieve the near perfect fruit that appears in the store. This can be a difficult schedule to maintain and possibly even detrimental to the beneficial insects that are important to your yard.
Home orchardists should accept a new attitude of some tolerance to less than perfect fruit. Cutting out bad spots, as you do, is perhaps easier to do and better for you and your environment than following a heavy spray schedule to eliminate those few bad spots. There are general sprays, which can be used, but timing is critical to success. This schedule is often impossible for the home fruit grower to maintain.
A lot of problems with fruit can be eliminated by a thorough clean up in the fall. Over wintering disease such as apple scab can be eliminated by raking up fallen leaves and fruit. This clean up also reduces the problems brought on by the coddling moth whose tiny white larvae tunnel into fruit. Since these insects survive in the bark of the trees, use corrugated traps wrapped on the tree trunks in the fall, and destroy the traps and resultant caterpillars in the winter.
Traps are available for other apple insects as well such as the apple maggot. The readily available traps capture the adult flies before they have a chance to lay eggs in the fruit.
Dormant horticultural oil sprayed in March and April is also effective in controlling some fruit problems, such as scale which will weaken the tree, as well as some spider mites.
Correct pruning is also essential to the health of the tree, since an open tree with good air circulation is less susceptible to the many fungal problems which can damage fruit.
Lastly, encouraging woodpeckers and other birds to the area is a great way to have the insects "hand picked" from your trees without the need for potentially dangerous chemicals. Winter-feeding of the birds not only is helpful to your trees, but a fun winter activity. Contact your local library or your county extension office (ph no. 614-462-6700) and ask them for more information on methods to control pests on apple trees without chemical use.
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