September 2019 – Crop of the Month
Pecan – Scientific Name: Carya illinoinensis
Written by: Kirby Fry
The pecan tree is iconic. It is a tall, beautiful and agriculturally productive native tree.
The pecan tree is also the state tree of Texas.
Since the 1880’s the United States of America has become a major producer of pecan nuts, which are actually drupes or stone fruits, harvesting 264.2 million pounds of pecans annually as of 2014. Mexico and the US of A account for 93% ton of the world’s pecan production.
Growing up in Houston, Texas, my second story bedroom was perched over our neighbor’s single story house which had a metal roof on it. I remember hearing pecans falling from their pecan tree and hitting that roof all throughout the fall. During those fall and winter months there was also a wooden bowl that sat out in our dining room which was full of pecans. Nearby was an assortment of tools used for cracking open the shells and picking out the delicious fruit inside, we had contests to see who could “shell” the most intact pecans.
Right around the fall equinox, pecans are ripening here in Texas. This is a really good time to start thinking about planting your very own pecan trees.
The pecan tree can be planted from late December through early March and will do well in every county of Texas. They are typically sold as bare root stock with a 24” to 32” long intact tap root.
The roots of a pecan tree should be kept moist from the time of purchase to the time of planting.
At least 2 or 3 different varieties should be selected and purchased for cross pollination.
Cultivar pecan trees are grafted and chosen for the sweetness of their fruit, the thinness of their shell, and the alternating years that they produce. Pecan tree growers are careful to select trees that yield pecans during alternating years, as a pecan tree will produce one year and then possibly skip 1 or 2 years of production.
Several varieties of pecan trees are recommended for Central Texas. These varieties include – Sioux, Choctaw, Wichita, Cheyenne, Pawnee, Forkert, Cape Fear, Kiowa, and Caddo. They have all adapted to river and creek bottoms, preferring deep well drained sandy and loamy soils, though I have also seen them do well in clayey soils that have good drainage.
Select a site to plant your pecan trees that is at least 20’ away from your house, and away from driveways where cars will be parked. Pecans are large trees that tend to start dropping large branches after 20 or 30 years of growth. If planted close to your home, they will need careful pruning later on in their life cycle.
Pecan trees should be planted 35’ apart from one another in order to give their massive root systems plenty of room to develop.
The hole you dig for them should be as deep as the tap root is long (sometimes 32” to 48” deep), with the objective being to replant the tree as deeply as it was planted at the nursery. The soil line on bare root trees can be determined by the color of the bark.
Because the hole you will need to dig for a pecan tree will be deeper and larger than most fruiting trees, the tap root should sit firmly against the bottom of the hole you dig to avoid undesirable settling. The hole should be carefully back-filled and watered in, in order to prevent branching roots from settling or sinking too much as well.
The tree should be watered in with at least 5 gallons of water per tree immediately after planting.
The time needed for the tree to begin production takes close to 8 years, after which the tree will begin to yield 10 pounds of pecans per year and up.
Tree Fertilization and Maintenance
A nitrogen fertilizer should be the only soil-applied amendment that your pecans need. Alfalfa meal, feather meal, bone meal, and/or blood meal should be applied in small amounts throughout the growing season. These are low or moderate sources of nitrogen and you could easily double the amount applied when compared to high nitrogen fertilizers.
About 1 pound of high nitrogen fertilizer (21-0-0) per inch of trunk diameter should be applied each year. Keep high nitrogen fertilizers away from the base of the trunk in order to prevent tissue scalding.
As the trees mature into their 7th or 8th years of growth, avoid applying high nitrogen fertilizers after June in order to prevent a flush of new growth getting frozen back in the fall.
During the first 7 years of growth, a zinc nitrate solution should be applied in a liquid form to the surface of the leaves, 2 to 4 teaspoons per gallon of water or 1 to 2 quarts per 100 gallons of water. Pecan trees deficient in zinc will have smaller, weaker leaves and leaf stems and in extreme zinc deficiencies the trees will experience a higher rate of die back during harsh summer and winter conditions. This zinc emulsion should be sprayed on the trees every 2 weeks or so during the growing season.
Water your pecan trees from March through September for the first couple of years after you plant them. During the summer time your young pecan trees may need 2” of water per square foot of growing area, one time per week.
Low emerging braches (a.k.a. trashy trunk) should be pruned back each winter, and care should be taken to select and preserve a central leader for the top of the tree. Try to avoid allowing a “V” to form in the tree’s trunk as pecans grow to be large and somewhat brittle, and a forked trunk will often crack and split.
Maintain the area under your pecan trees and keep it free of brush and tall grasses during the fall so that the fallen pecans can be more easily harvested. Once your pecan trees are established after 8 years or so, fertilize and water only as needed.
Harvesting pecans is a great way to supplement your fall and winter diet. Pecans also have a high market value and can be used to feed pigs during fall and winter months.
Take a look at your property, and find a good place to plant a few pecan trees.