Ask Mr. Smarty Plants

This is one of those things that everybody has an opinion and/or theory on. Even the experts change their minds ever so often. If you Google on "wood chips as mulch" you will run across one garden forum after another, chock full of the opinions of each contributor, often conflicting.  A blog from PennLive.com on Fresh wood chips as mulch pretty much summarizes our opinion.

The decomposition of those wood chips is going to introduce some acidic content into the soil. In Central Texas, we have a pretty alkaline soil, and a little acid couldn't hurt. However, we also agree that oveuse of fresh wood chips can have a negative effect on the plants growing there. We are great believers in the compost pile. Composting those wood chips for a year or so, spraying a little water on it when there has been no rain, and throwing grass clippings and other green matter for nitrogen in the pile will make a wonderful mulch/soil enhancer. The blogger we referenced says it's okay to just pile up the chips and let them rot for a while. 

Since, as you say, there is an abundance of these chips, often free, it's hard to turn down that opportunity to recycle the leftovers of clearing and cleaning up woody plants.  If you really want to use the chips right now, no waiting for composting, don't use more than about an inch on the soil, and if you are concerned about the nitrogen, sprinkle some high-nitrogen fertilizer, like for lawns, on the soil before you put down the mulch. Not too much though, if you are growing native plants they don't need fertilizer and high nitrogen fertilizer can promote more leaves and fewer blooms in the plants you are mulching.