Published on 06/24/96

Water Vital for Young Pecan Trees

The No. 1 reason Georgia-planted pecan trees die in their first two years is that they don't get enough water.

Many homeowners forget that a newly planted pecan tree has a very small root system. It is extremely important that these small trees get ample moisture on time every week. One way to make sure the trees get enough water is to give them at least five to 10 gallons every week.

A complicating factor is the lack of weed control around the tree. Research has shown that just mowing grass around young trees can reduce growth by 50 percent to 75 percent.

The grass competes with the young tree for water. Even if you water the tree weekly, the grass tends to get the water and the nutrients. By using herbicides to control grass and weeds in a three-foot-diameter circle around the tree, growth was increased by 75 percent.

You can keep weeds under control with by several household herbicides you can buy at your garden center.

In the research plots, the trees that grew the most were the ones that got mulching plus weed control. Your tree will grow its best, too, if you mulch a three-foot-wide circle around the tree with three to four inches of old grass clippings, pine straw, pine bark, etc.

The mulch will preserve moisture and enhance the tree's growth. When weeds were kept under control in the mulch, the research trees grew as much as twice as fast as the trees growing in grass sod.

So it's critical to water young pecan trees weekly, mulch them and control weeds around them for the first two years.

Weed control around the tree, and in strips through commercial orchards, is a good practice for older trees, too. It will conserve moisture while it protects the base of the trees from mower injury.

Tom Crocker is a horticulturist with the University of Georgia College of Agricultural and Environmental Sciences.