Fruit Bugs, Diseases and Pests.
I have been growing fruit in my yard for years and so far things are not getting easier. I am always looking for the magic information. :)
Watchfulness and know your Bugs:
Everything day before my day begins, I take a walk through my garden. I look for pests and disease infestations.
I look for holes in leaves, wilting, shiny coating on leaves, holes or cuts in fruit, yellowing on leaves, premature defoliation, distorted growth on fruit, blistering of bark.
Once you identify a specific problem, learn about the life cycle of the pest involved. I find the secret on how to get rid of one problem and then I find another. I think I had more pests last year than the year before.
For attack on fruit trees including citrus, many barriers are linked to controlling pests at a particular point in its life cycle. Pheromones traps will help monitor leafrollers. Bt (Bacillus thuringiensis) or rotenone sprays provide control, that is if you can find it where you live.
Encourage Pest Predators:
Birds eat a lot of insects and insect eggs hidden under the tree bark. Encourage them to visit by providing, water, food and shelter. However, some birds could also be pest by eating you other fruits like; currants, berries and grapes.
Parasitic wasps and other beneficial insects also help control many fruit trees pests.
Harvest thoroughly and pick up dropped fruit:
Windfalls or damaged fruit on the tree are prime targets for pests and diseases. Burn diseased fruit and prunings.
Prune carefully:
Good pruning keeps the tree open for light and air, discouraging many disease organism that strive in a wet, humid environment. Disinfect pruning tools with bleach, rubbing alcohol between each cut.
Use Horticultural Oil:
I did buy this at Canadian Tire and it wasn't as expensive that I thought it was going to be. I think it was under $30.
Oil spray will coat the insect on your trees and killing them. These should only sprayed in winter or early spring when trees are leafless. I like to do it during winter when the trees are dormant. The instruction how to apply the dormant oil comes with the kit. This spray will also kill spider mites and other soft-bodied sucking insects.
Care and Maintenance
Bacteria, fungal spores and dormant insects can overwinter in leaf litter under fruit trees. Clear any debris around the trees and cultivate the top 1 - 2 inch to expose pupae of some insects to weather and predators.
Spray when critical:
If faced with a choice of losing your tree or spraying.
BT and many other botanical poisons are effective against many tree pests. Lime sulfur, copper and bordeaux is effective against many tree diseases and considered low in environment toxicity.
Common fruit tree pests
Apple Maggots
These are the larvae of flies that lay eggs on fruits throughout the growing season. Catch and kill the flies by hanging red spheres ( I use ping pong balls and sprayed it red ) coated with Tanglefoot or other adhesive substance and hang the spheres from the branches. Use 1 trap for every 100 or so apples you expect the tree to bear.
Cankermoths Moths
Cankermoths skeletonize the leaves of apple, apricot and other fruit trees. Wrap heavy paper or cotton batting around tree trunks and coat with sticky adhesive to stop the female from climbing into the tree and lay her eggs. Bt (Bacillus thuringiensis) sprays are effective against the larvae. Tilling the soil around your trees in the fall may help unearth pupae, exposing them to predators.
Coddling Moths
Apple coddling moths larvae, which burrow into apple, peach, pear, apricot fruit, can be controlled with Bt (Bacillus thuringiensis) Just as eggs are hatching. Sticky red spheres and oil sprays, also helps in controlling pests. Woodpeckers will eat the eggs hidden in the tree bark, but I'm sure if I want Woodpeckers pecking at my fruit trees.
Gypsy Moths
The larvae will feed on the foliage of many fruit trees, can be controlled with Bt sprays. Also trap larvae with a sticky band around tree trunk. Older larvae feed at night and hide during the day.
Japanese Beetles
I just found these this year in my yard eating the plum and grape leaves. I just hand pick them and drop them in soapy water with a tablespoon of oil.
Leafrollers
Leafrollers are easy to find. I look for the curled leaves and squish it. I have espaliered dwarf fruit trees. I can see them. :)
They will attack most fruit trees including citrus. Bt and rotenone sprays provide control.
Peachtree Borers
The larvae of these pests tunnel into the trunks of apricot, cherry, peach and plum trees, weakening and sometimes killing the trees. Kill the larvae in the holes the have made by inserting a wire and spear the pests. Spraying Bt in the hole will also work. The months will lay eggs near the tree base in late summer and early fall.
Pear Psylla
If you tree appear to be covered in soot, they probably have been attacked by pear psylla. These tiny insects secret a sweet, sticky substance. During the growing season pear psylla can be controlled with Bt, diatomaceous earth, ground limestone or insecticidal soap.
Plum Curculios
These pests lay their eggs in fruits of most common backyard fruit trees. When you notice damage on your fruits, spread a white dropcloth and shake the tree or branches. They will drop from the branches, immobile and you can collect and destroy them.
https://extension.usu.edu/pests/research/insects-treefruit