It’s my pleasure to introduce Aaron Voigt, who is writing a guest column this week. Aaron is a summer intern here in our North Dakota State University Cass County Extension office and is a senior majoring in Agricultural Education. Aaron is from Mohall, N.D.
The care of your apple tree during June not only helps it produce a large crop of apples, but helps improve the quality of the fruit. Multiple things affect the apple harvest, and timing of tasks is an important factor.
First, take a look at the apples on the tree, and check to see if they are crowded. You can remove the smaller fruit, and any that appear damaged, so the remaining apples will grow larger and healthier in the coming months.
This thinning improves the quality of the apples. It might vary in how effective it is on each tree, but it can help reduce stress on a tree that is trying to produce too many apples. Thinning the excess can reduce branch breakage also.
June is an important month to observe apple trees to decide whether trimming branches might help the tree produce more fruit. Even though it’s not recommended to prune the trees now, it’s a good time to plan ahead.
If some branches aren’t producing much fruit, maybe pruning next spring might help, at the recommended time. Removing crowded branches at that time can help prevent disease that might happen in a tree that’s too dense. Observing the tree now can help identify branches that need pruning.
Any dead branches should be pruned away now, when they’re easy to identify. Care should be taken not to damage any of the live branches of the tree while removing dead parts.
June is a good time to put woodchips or compost around your apple trees. This helps the soil retain water, and allows the tree to grow better and stay hydrated. The mulch prevents unwanted weeds or grass from growing next to your tree. As an added bonus, the mulch around trees makes the yard look nice.
Insect problems are common on apple trees, and the most common insect is the apple maggot. The larvae of these insects are creamy white, and they leave brown trails through the apple. The damage often isn’t noticed until the apples are picked, and the streaks are found when the apples are cut open. By that time, the larva has usually left the apple.
There are a couple of ways to control apple maggots. You can spray for the adult flies before they have the chance to lay eggs on the apples. The eggs hatch into the larvae that tunnel into the apples. The types of insecticides that are most effective include carbaryl, malathion and spinosad. Always read and follow the directions on the label.
Because the flies continue to lay more eggs through the growing season, spraying every seven to 14 days is necessary until the adult flies stop laying eggs in August. Spraying doesn’t always prevent all maggot damage, but it helps to minimize it, and reduces the maggot population for next year.
Another way to reduce apple maggot damage is by picking up all infected fruit as it drops from the tree. This removes the fruit before the larvae have a chance to go into the soil where they survive winter, waiting to reinfect the tree again next year.
This week's "Growing Together" column was written by Aaron Voigt, an intern in the North Dakota State University Extension for Cass County office. Don Kinzler, a lifelong gardener, is the horticulturist with NDSU Extension for Cass County. Readers can reach him at firstname.lastname@example.org.