I just moved from Santa Fe (where I am a master gardener) to Houston. In Santa Fe, I raised a nectarine, a plum, numerous chokecherries and one Nanking cherry.
Fruit trees in northern NM have a problem with insects wintering over, either as eggs or pupae beneath stems, in the crotches of stems, and beneath the trees in debris and/or mulch.
I would suggest several solutions to your insect problem.
1. In the fall, completely remove any mulch or other debris from beneath the tree. Replace it with fresh mulch (I have used hay straw (usually available from area farmers or from feed stores at about $4.00 a bale), cedar mulch or cypress mulch. Hay straw is okay, but the wind in northern NM plays havoc with it, and before you know it, you've got straw everywhere. I prefer the cedar mulch, which has a nice smell, is somewhat repellant to insects, and it looks nice. About three-four inches of new mulch around the base of the tree, out to the drip line should suffice. Make sure you don't lay the mulch directly up against the trunk of the tree, as this could encourage diseases to flourish.
2. Next, obtain some "dormant oil" from your local nursery, and follow the spraying directions. Dormant oil should be sprayed in the fall or winter.
The dormant oil will coat the exoskeletons of the overwintering insects, as well as coat pupae and eggs, effectively smothering all or most of the insects and their potential offspring.
I hope this helps. You also might want to check out the website below for more information,

Here is a link that might be useful: Xeric Gardening 101