Cleanup of Pecan Trees Broken by Ice Storms

by Scott Landgraf

Pecan growers across southern Oklahoma are fortunate that the weight of 1 to 1.5 inches of ice that formed on trees during December's storm did not cause even worse damage. At Madill, I gauged that 4.2 inches of rain fell. Had a large portion of that water accumulated on trees and power lines, the mess would have been even larger. As bad as it was, the damage was on the verge of being even more devastating (figure 1), particularly if the wind had begun to blow.

Figure 1. Severely broken limbs of a pecan tree (All photos by author)

Now that the storm is over, the ice is gone, and the soil is beginning to dry, it's time for the cleanup, but how, what, and where? The first thing you may need is assistance, which is going to vary from county to county. The only way to know what is available is to contact the Consolidated Farm Service Agency office that serves the county where your orchard is located. The agency offers very limited financial support.

Don Hassel with Five Star Ranch at Okemah said that in 1987 an ice storm damaged his orchard, the cleanup cost over $100 per tree on a few acres, and he had 3,000 trees. He cleaned the debris from under the trees for $12 per tree.

Cleaning your orchard can become overwhelmingly costly if done correctly from a cultural point of view. Most commercial pecan producers must consider economics. Yes, it would be best to use a man-lift and go through the entire orchard, cutting each break back to a scaffold limb to expedite healing, but some orchards I have seen would take unbelievable time to repair.

Figure 2. Regeneration of pecan limb damaged four years earlier (click image to enlage)

During tours of native orchards, pecan experts from other states have had significant discussions about the lack of proper cuts as a response to limb breakage in native trees. They are amazed how well a healthy tree can heal most of its injuries. The question is, if you decide to repair your orchard, how much money can you spend on man-lifts and hydraulic saws for cutting broken limbs from the tops of trees? There are several points to consider in making those decisions:

• Man-lifts rent for $1,500 or more per month.
• Hydraulic saws usually cost more than $1,200.
• Labor is $6 to $8 per hour, according to experience and area.
• Pecan trees with dead limbs hanging in them can still bear nuts.
• Pecan trees can heal wounds caused by breakage or removal of limbs.
• The rooting process will smooth jagged edges for healing in healthy trees.

In your yard or over your driveway, it would not be wise to leave dead limbs hanging in trees, although out in the native orchard, it may not be cost effective to spend the money to remove broken limbs from the tops of large trees. Since the trees will generate a new bearing surface along a limb stub, even if someone were to make cuts in the top of a tree to remove debris, it would not be wise to cut the stubs off to the supporting limb (figure 2).

Figure 3. Healing one year after a 4-inch cut Figure 4. Healing three years after a 4-inch cut Figure 5. Healing ten years after a 4-inch cut

Consider the factors involved in stimulating pecan trees to produce pecans consistently; the factors are listed from most to least important:

• orchard floor in condition to facilitate harvest
• deep arable soils
• adequate nutrients and moisture available for pecan production
• adequate space for canopy development for capturing energy from sunlight
• insect and disease control

These factors are like blocks used in constructing a building. Do you see that trash hanging in the trees is a deterrent to consistent pecan production? How much money can you spend to make the orchard look better? Orchard owners must decide for themselves because the greatest asset to the healing process is a healthy tree (figures 3, 4, and 5).

Cleaning out the tops of broken trees makes cleanup at harvest easier, which is a significant benefit. When the trees are shaken to put the nuts on the ground, brush from trees whose tops were not cleaned will fall in abnormally large quantities. It is much easier to remove such brush than to cut it out of the top of the trees. From a cost-and-returns point of view, spending money on the factors necessary for consistent crop production makes more sense than spending money for the orchard to look better.

Undoubtedly, limbs that are resting on the ground and hampering necessary ground activities should be removed. It is normal in any pruning operation to put all debris on the ground and then use some form of brush rake to push it out of the orchard for burning. There are several versions of rakes, from those that fit on the blade of a dozer to those that work on the front-end loader of a tractor. Determine which one to use by the size and scale of the debris you must move.

It is sad that such a disaster has happened to such stately trees. It is a part of their life, though; some will survive and not be weakened, while others will begin to decline. Where there are large injuries that will not heal for several years, insects and disease will begin the deterioration process, making that tree short-lived. If you want to perpetuate pecan production in those areas of the orchard, you must plant new trees. For information on planting and developing new trees, visit www.hortla.okstate.edu/pecan/ or your local Oklahoma State University extension office.