Many homeowners enjoy growing their own fruit, but they have also learned that they require a lot of care to approach the quality of products obtained from a commercial orchard or grocery store. Pruning, pest control, fruit thinning, harvesting, and storage are among the tasks an orchardist must undertake each year. The activity of pests is particularly disheartening to the home fruit grower, and it is the subject we’ll concentrate on today.
A backyard orchard in northern Indiana typically consists of varieties of apple and/or pear trees. Except for occasional late freezes after bud break some years, our climate is suited to these fruits. Some may also grow stone fruits (fruits with a single, hard pit) like peach, apricot, plum, or cherry trees, but these fruits are generally more difficult to grow successfully and consistently by the backyard grower.
Among the pests that apple growers may deal with are scale insects, aphids, mites, plum curculios, codling moths, apple maggots, and Japanese beetles. The “worms” we find in apples are the larvae of codling moths. I’m reminded of an old joke that goes like this: “Do you know what’s worse than finding a worm in your apple? Finding half of a worm.”
Scales, aphids, and mites are all quite small. They can typically be controlled with an application of superior oil spray in the delayed dormant season (right before buds swell and break open with new growth). Other pests will generally require insecticide sprays at the right developmental stage for effective control.
Pests are not only insects but also diseases. Diseases affecting apple trees may include fire blight, apple scab, sooty blotch, fly speck, rust, and fruit rots. Most of these are fungal diseases, but fire blight is a bacterial disease. Correct diagnosis of a disease is important so that proper selection of a management product may be made. Once again, the timing of applications is very important, and it typically happens at regular intervals during appropriate growth stages through the growing season.
Some years we see severe cases of fire blight – a disease that affects both apples and pears. A common symptom of fire blight is a burnt appearance of the tips of limbs, with the terminal growth curving back in a shape resembling a “shepherd’s crook,” or the curved end of a wooden cane.
Fruit growers dealing with this disease are encouraged to prune affected branches at least 12 inches below the transition on the stem between diseased tissue and normal growth, and also to disinfect the pruning tool between every cut in a 10% bleach solution. Prune only on a dry day. Early next year, apply a copper-based pesticide like Bordeaux mixture or another dormant spray mixture before bud break. Streptomycin may also be applied during the bloom period according to label directions.
Pears have many of the same or similar insects and diseases that affect them, although diseases such as pear scab are caused by a different fungal species than the one that causes apple scab.
Many home orchardists choose to raise apples or pears in a system where only naturally derived products and pest control methods are employed. Even with extra vigilance and management, they may not end up with pristine fruit, but it’s what they prefer.
Purdue Extension has a publication authored by experts entitled, “Managing Pests in Home Fruit Plantings.” The publication describes (with representative pictures) the developmental stages of tree fruits. This is helpful when deciding when to properly apply certain pesticides. It also describes cultural practices that help prevent or reduce pest problems. And, it includes a spray guide for each tree fruit, describing typical pest problems at various developmental stages and optimum times to utilize chemical controls.
The publication also includes similar pest management information for small fruits, including grapes, strawberries, raspberries, blackberries, currants, and gooseberries.
Find your copy of the aforementioned publication at: www.edustore.purdue.edu.