2025 began with promise. Plenty of rain early. What appeared at first to be a good crop set on pecans. Life looked good. Who would have thought that stick tights would be a problem by fall?
As summer progressed, rain ceased in many areas. Some of my southern friends received good rains in late summer. But, it got very dry in the mid south and mid west.
Scab prone varieties were hammered by the early rains. High humidity combined with hot temperatures wiped out susceptible pecans that did not get scab control early in the season.
The scab resistant trees looked good though. Normal summer nut drop from the hot weather. We always attribute this to poor pollination, but that is only partially to blame.
Harvest time comes and the shucks don’t split. The weather is still dry. A few showers, maybe an inch over 2 or 3 weeks falling on bone dry soil makes no difference.
Makeshift irrigation might help some, but it isn’t enough.
Harvest is light and quality is poor. Most of us shrug and hope for a better year next year.
But, let’s understand what is happening and why.
Drought Stress and stick tights
Drought stress is a problem for pecan growers. In our case, this was moderate drought with a few trees actually showing symptoms of stress.
Most trees showed no serious sign of stress until the most important (to me) part of the season, harvest.
It seems counterintuitive that pecan trees need water to dry shucks and release pecans. Trees are giant water pumps. Adequate water is required for them to function properly. This is particularly so for pecans to fill the nuts fully and for the shucks to pop the seams for the nuts to release. The shucks must be healthy to complete their task of feeding and protecting the nut inside. When the tree is drought stressed, these functions do not progress properly. The seams stay shut and nuts are trapped inside.
If you have experienced scab infected pecans, you will have seen shucks that would not release due to scab. Drought stress causes a similar lack of release.
Nuts in the shuck are harder to shake from the tree and soured shucks discolor nut meats and leave a bad taste.
Insects Amplify stick tights
Other stick tight factors are, pecan shuck worms, and possibly severe stick bug damage. In good years, most nuts come off easily and some shuck worm stick tights are accepted. Some Shuck worm affected nuts release or mostly release and we deal with that during cleaning. In a dry year, they don’t release at all. The nuts are useless if there is any size crop because it is uneconomical to try and remove them by hand.
Some of those summer drops were 2nd generation shuck worm damage and stink bug damage. By harvest, we are seeing 3rd generation shuck worms.
Another factor in shuck split in incomplete filling of the kernel inside the nut. The hormonal and physical signals that the job is done are incomplete so the shuck hangs on trying to complete its life’s work.
