Late season drought: When should you turn off the irrigation?
John McLemore, County Extension Agent
This week’s article is a blog post from the University of Georgia pecan web page. Dr. Lenny Wells, UGA Pecan Specialist, wrote an informative article about the current environmental conditions, and solutions to reduce yield loss in pecan orchards.
I’ve had a number of calls so far this week and the end of last week asking, “when is it ok to turn off the water?” You can usually cut way back at this point. The problem is that we are in a severe drought which makes it very risky to stop irrigating, especially if you have a crop load on the tree. If you are not irrigating enough at this point you likely see some yellowing of the leaves and some leaf drop.
For young, non-bearing trees, continue to irrigate on the normal schedule-100 gallons per week-until you get an inch rain. At that point you should be able to turn off the water for the season. If the drought continues long-term, continue to irrigate until the leaves drop naturally.
It is especially critical to continue irrigating trees bearing a crop. If you turn off the water too soon at this stage under the conditions we currently have you will likely see significant shuck decline, stick-tights, and loss of quality. This problem will be worse on trees with a heavy crop load. The nuts are still maturing on most varieties and even though the kernels have filled, the process of shuck dehiscence (opening of the shucks) requires good soil moisture.
Continue irrigation at 50-60 percent of full capacity on bearing trees until about 1 week before you expect to shake trees for harvest. If you get an inch rain you can turn the system off for 3 days and then resume irrigation until the leaves drop or until we get another good rain.
Most growers with Pawnee are shaking this week or next week. Following the harvest of these nuts I would continue irrigation until an inch rain arrives or until trees lose leaves.
It is extremely dry throughout most of the state. Don’t make the mistake of turning off your irrigation too soon under these conditions.
Written by Dr. Lenny Wells (UGA Pecan Specialist)