Monday, December 28, 2015

Leaf Miners in Fruit Trees

A leaf miner is not a specific type of insect, it is a way of describing an insect's feeding habits. Leaf miners are the larva of caterpillars, beetles, or flies that feed between the epidermis of a leaf. The following example is from the order of Lepidoptera, or in other words a caterpillar.

Leaf Miners Feed Between a Leaf's Epidermis
What makes leaf miners challenging to control is that they use the epidermis as a shield to protect them from beneficial insects and organic pesticides. So how do you control leaf miners in fruit trees?

If you have leaf miners in your tree you can squish the larva inside the leaf, or remove and dispose of the affected leaf all together. It may not be feasible to squish or remove leaves in a serious infestation so organic pesticide control may be necessary, unfortunately pesticide use will not penetrate the epidermis unless a systemic pesticide is use which is not recommended, so it is important to monitor your tree closely to see when the miners begin to emerge from the leaf.

Treatment Must be Done When the Leaf Miner Emerges
It is important to know the life cycle of the leaf miners that are infesting your trees. Some leaf mining insects will emerge from the leaf and then pupate. If these insects are exposed to an organic pesticide before they enter their cocoon, you will be able to interrupt their life cycle, preventing or minimizing future infestations.

Treatment Before the Leaf Miner Pupates Will Increase Effectiveness
With all pest control, knowing your target pest's feeding habits, breeding habits, and life cycle will increase your ability to keep this pest at bay.

For more information about the care and pruning of fruit trees please follow the links in the right column or send me an email at russ@simplytreesut.com