Over the years, people have written songs and poetry inspired by the green leaves of summer. To pecan producers, the appearance of those green leaves should inspire more than just poetry; they should inspire growers to get out and take leaf samples from the trees.
Leaf sampling is a vital tool a grower can use in identifying the nutrients needed for the orchard. July is the standard time to collect leaf samples. During this time of the year, nutrients are more balanced, and standards for the nutrient concentrations have been well-documented.
Sometimes, I am asked by cooperators what a leaf sample will tell them that a soil sample can't. The answer: although a soil sample can help identify the nutrients available in the soil, it cannot identify what nutrients are being taken up by the trees. In fact, there is no direct correlation with soil samples and leaf (tissue) samples. That is why taking leaf samples is critical for pecan management. A leaf sample can accurately pinpoint the nutrient status of trees in the orchard. Also, if you have a problem tree, a leaf sample can assist in identifying potential nutrient deficiencies and assist a grower in improving the health and overall production of that tree.
Pecan producers should consider leaf sampling a vital task in maintaining the overall health of their orchard and should make sure it is done on a yearly basis to consistently meet the trees' nutrient needs. It can also be a cost savings tool. Through a consistent leaf sampling routine, producers can fine-tune their fertilizer program and potentially realize a cost savings.
Before you start collecting samples, it is important to identify how you plan to manage your orchard. If you are going to have consistent management practices across the orchard, taking a random sample across the orchard is adequate. If you are willing to change the fertilizer management plan throughout the orchard, collecting multiple samples throughout the orchard is ideal but be sure to keep track of the areas you sample. To get an idea of overall orchard health, it is important to collect from multiple trees. However, if you have certain problem trees, you could collect just from those trees separately to get an idea of what is needed to correct any potential deficiencies.
Beginning and maintaining a testing regimen is an important step in establishing an efficient fertilization program, which can maximize productivity while saving money by pinpointing specific nutrient needs. So, when those green leaves start blowing in the summer breeze, be sure to start sending in leaf samples to your local leaf testing service.
How-to Guide for Submitting Your Pecan Leaf Samples
Before you start collecting samples, it is important to identify how you plan to manage your orchard.
Step 1
Collect at least 100 middle pairs of leaflets from the middle leaf of the current growth. Avoid leaflets that show damage by insects or disease, from suckers, or water sprouts.
Step 2
Collect samples in a paper sack. Once samples have been collected, wash leaflets in tap water for less than one minute. This will help to remove any spray residue or dirt.
Step 3
Spread your leaflets out to air dry until they can easily crumbled. Once samples are dry, place them in a paper bag for transporting. Do not send wet leaves or use plastic bags. You want to avoid any excess moisture.
Step 4
Be sure to completely identify each sample that is sent by including the variety (improved or native) and age of the trees. Also, be sure to specify if you are sending samples from problem trees or deteriorating areas in your orchard.