There’s nothing quite like being able to walk into your backyard and pick fruit straight off the tree for a healthy, natural snack—or to use in a favorite family recipe. But for people with fruit trees on their property, there are few things more frustrating than a harvest that’s been ruined by a pest infestation. Fortunately, most common pest problems can be effectively managed with the right tools and the right knowledge.
What pests should I be on the lookout for?
Depending on the particular fruit trees you have on your property, you’ll be dealing with different potential invaders. Knowing what species and symptoms to watch for is the first step in protecting your fruit harvest.
|Codling Moth: Apple and pear trees are commonly affected by codling moths, who lay their eggs on and near apple and pear fruit. Larvae then tunnel into the fruit and feed on the seeds. Symptoms you may be dealing with a codling moth larvae infestation include visible entry & exit holes in fruit, tunneling in fruit flesh (specifically around the seeds), and fruit that drops off the tree seemingly ahead of schedule.|
|Western Cherry Fruit Fly: The most common pest terrorizing sweet, tart, and wild species of cherry trees—in extreme infestations, you may find maggots in every single cherry. Indicators include small holes in fruit, larvae floating in cherry harvest tanks, and collapsed fruit.|
|Greater Peachtree Borer: Peach, nectarine, apricot, plum, and cherry trees are commonly infested by the greater peachtree borer, a clear-winged moth that lays its eggs at the base of tree trunks. Larvae bore into tree trunks, which can kill young or already-stressed trees. Classic symptoms include loose, dead bark, holes near the soil line, or oozing sap mixed with frass (dry, tiny, pellet-like insect excrement) around the base of the tree.|
|Peach Twig Borer: Peach, nectarine, apricot, and plum trees are also affected by the peach twig borer, whose brown larvae tunnel into the shoots of budding trees before feasting on fruit later in the season. Symptoms of peach twig borer infestation include wilted twigs, and small amounts of gum seeping from tunnel openings. Larvae typically enter fruit through the stem end, and may leave frass at the opening of the tunnels they chew.|
|Aphid (Various): Different types of aphids also affect most kinds of fruit trees. Aphids lay their eggs during the winter in different locations depending on species. Telltale signs of aphid infestation include curled leaves, honeydew (which is actually aphid waste), generally reduced tree health, and occasionally sticky, deformed, or aborted fruit.|
How do I choose the right pest-control product?
There are several of options available that will work to control a variety of pests on many different fruit trees. We typically recommend fruit tree sprays with a combination of insecticide and disease-control ingredients; including, but not limited to: Bonide Fruit Tree & Plant Guard; Bonide Fruit Tree Spray; Bonide Malathion Insect Control; Hi-Yield 55% Malathion; and Hi-Yield Lawn, Garden, Pet & Livestock Insect Control. Bonide Captain Jack’s Deadbug Brew (active ingredient: spinosad) is an approved organic gardening option that’s effective on various insects as well.
Whatever you choose, keep in mind that it’s wise to rotate different products with different active ingredients to prevent pests from building up a resistance to any one product. Ideally, you shouldn’t use a product with the same active ingredient more than twice in a row.
There are also dormant sprays available, which help control overwintering pests like aphids, scales, mites, and peach twig borers. Used in late winter or early spring (before trees begin budding), dormant sprays coat your trees with a horticultural oil that effectively controls pests by suffocating the eggs layed late the previous year.
Keep in mind that whatever pest-control products you choose, the goal is control rather than eradication. It’s nearly impossible to completely eliminate pests—but with a little care, you can keep them at an acceptable level to maintain healthy trees and hearty harvests.
What time of year (and how frequently) should I spray?
Dormant sprays should be applied in the late winter or early spring (before the first buds appear on your trees.) Once you notice new buds growing, it’s extremely important to wait until after all buds drop before spraying any additional pest-control products, as this helps keep bees safe during pollination season.
Because each type of fruit tree has its own pest species that need to be monitored and controlled, the particular pest you’re dealing with will dictate the spraying schedule, as well as the best types of chemicals to use.
- Codling Moth: You’ll usually need to spray multiple times between April and June, depending on outside temperatures. Different products require different intervals, so make sure you read the label carefully.
- Western Cherry Fruit Fly: Spray as cherries are turning from green to red (they’ll be a yellowish straw color when it’s the right time). Products including the active ingredients malathion or permethrin are often good options.
- Greater Peach Tree Borer: Pest control products containing permethrin will be your best bet. You’ll want to spray multiple times between June and August, starting about three feet up the trunk and working your way down to the soil around the base of the tree.
What safety precautions do I need to take?
When applying pest-control products, it’s always a good idea to cover up any exposed skin—think gloves, long sleeves, long pants, closed-toe shoes, protective eyewear, and a large-brimmed hat. Some products may even require use of a respirator—make sure to read the label closely.
Speaking of labels, one of the smartest things you can do for safety is carefully follow the directions on the package for each pest-control product. In addition to any recommended precautions and personal protective equipment, you’ll also find details each product’s pre-harvest interval (PHI), or the amount of time that must pass between the final application and harvesting the fruit. Even when adhering to each product’s PHI, make sure you wash your fruit well before eating to rinse off any leftover residue.
Finally, when applying any pest-control chemical, it’s recommended to spray early in the morning or in the evening, when temperatures are cooler and winds are calm. Not only does this help prevent accidental overspray, temperatures of 85 degrees or higher can also make it difficult to control the rate at which your product sprays, and potentially introduce additional safety concerns.
Still have questions about the best way to manage pests on your fruit trees? Stop by your local IFA Country Store to talk to our certified arborists and other agricultural experts, and you’ll be well on your way to enjoying a healthy harvest this year!
Notes: Utah State University Extension provides a helpful pest advisory that provides home fruit and vegetable growers with valuable information on which chemicals to use and when to use them. Take a look at pestadvisories.usu.edu for more information. The USU Extension also provides the “Intermountain Commercial Tree Fruit Production Guide” with up-to-date information on all fruit crops grown in the Intermountain region, along with details on disease, pest control, spray chemicals and other resources.
Information for this article was provided by Todd Tolbert, CCA, Spanish Fork IFA Ag Center; Aaron Jaussi, Branch Manager, Provo IFA Country Store; Nick Loveland, Certified Arborist, Assistant Manager, Ogden IFA Country Store; East LaMothe, Branch Manager, Salt Lake City IFA Country Store; and Ken Holt, Lawn & Garden Category Manager, IFA Country Store.
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