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The pecan-nut tree is deciduous and can therefore only be transplanted during the winter. The best results are obtained when establishing orchards with trees planted during July and August. Orchards can be started by planting seeds in place, planting seedling trees and grafting them in 2 years, or planting grafted trees. Planting seeds in place is not recommended due to weed competition, excessive mortality, and delayed production. One advantage of planting seedling trees and then grafting them after establishment is the low tree cost. Grafting is time consuming, however, and requires considerable expertise in order to establish an orchard by this method. The most common and effective way to establish an orchard is by planting grafted trees. The cost of planting grafted trees is more than planting seedling trees but labor and grafting costs may be avoided. Pecan trees are most commonly planted as bare root transplants; however, container grown transplants may also be used. Bare root trees provide a lower initial cost and are more readily available. Transplant bare root trees while dormant, from July through August. The earlier they can be planted, the better, in order to get good root establishment by spring. Bare Root Planting Plant bare root trees as soon as possible after they arrive from the nursery. Circumstances often make immediate planting impossible. When in transit from the nursery, trees should be loaded onto a trailer or truck. Protect roots by packing them in wet hay or sawdust and wrapping the tree roots tightly with a tarp, which is then secured. Once the trees arrive, they may be stored for short periods of time (4-5 days) on a trailer with roots protected as described previously. Water should be continuously applied to the roots during this time. If trees will not be planted for an extended period of time, heel them in. Dig a trench wide and deep enough to bury the roots to the depth they grew in the nursery. Lay trees in the trench in a slanted position so they will not be blown over by wind. Cover the roots with soil and watered thoroughly. Mound the soil and firm it in around the roots to provide good surface drainage. Trees may then be removed and planted as needed. Dig holes for bare root trees with an 18” auger. Holes are normally 3 to 4 feet deep (depending on root size) and should be deep enough to accommodate the root system without bending the taproot. Keep the roots of bare root trees moist at all times before planting. Take care to prevent exposure of the roots to wind or sunlight to prevent drying. When centered in the hole, trees should be set at the same depth they stood in the nursery. This can normally be observed as a color change on the bark of the tree. It is critical that the tree not be planted too deep. When this occurs, the roots may die from lack of oxygen, leading to tree stress or death. Additionally, trees set too deep are often easily blown over in a storm when they reach 15-20 years of age. Arrange roots in a natural position. Although limited root trimming is permissible, root trimming usually should be kept to a minimum. Twisted or broken roots, as well as roots of excessive length should be trimmed to fit in the hole. Make every effort to keep the tap root as intact as possible; however, excessively long taproots may be trimmed to a limited extent if needed. After the tree is set at the appropriate depth, begin filling the hole with water. After the hole is 1/2-3/4 full of water, begin pushing dirt into the hole while the water continues to run. When the water level approaches the top of the hole, turn off the water and fill the hole with dirt (Figure 4). This will prevent the development of air pockets around the roots. Level the soil around the tree but do not pack the soil down around the tree. Very little soil settling should occur, but additional soil can be added after settling to bring the soil level with the surface again. It is not necessary to create a berm or basin to hold water around the tree. After the tree is planted, prune 1/3 to 1/2 of the top of the tree and remove any branches to compensate for the large percentage of roots lost when the trees are dug. When heading back the tree, cut at an angle just above a bud facing to the southeast. This will be the terminal bud that should develop into the central leader and will be somewhat protected from the prevailing northwest winds. Rub off all buds on the tree except the top two. By saving two buds, one of the two should survive and be available to form the central leader. If the uppermost bud exhibits good growth, remove the shoot formed by the lower bud. Protect the trunk from cold damage, herbicide, and wildlife for the first three years of growth. This can be done by painting the trunk with white latex paint or placing a 3 1/2 foot growing tube or sleeve over the tree. Containerized Tree Planting Containerized trees are planted much the same way as bare-root trees. After trees are removed from containers, check for potbound roots. If this is a problem, roots should be pulled away from the soil and pruned. If the taproot has become twisted at the base of the container, it should be straightened or cut to encourage the growth of new taproot. Place the root ball in the hole and add water and soil as mentioned above for bare root trees. The container soil mix can act as a wick and pull moisture away from the roots, so it is considered a good practice to cover container soil with an additional inch of soil to prevent roots from drying out. Irrigation of Young Trees Drought stress is one of the leading causes of mortality of young pecan trees. It is essential that young trees have access to adequate soil moisture. This can be accomplished through sprinkler, drip, or micro-irrigation. Drip and micro-irrigation sprinklers are probably the most efficient means of supplying moisture to the young pecan roots, which occupy a smaller volume of soil relative to those of a mature tree. With these two methods of irrigation, water can be applied more directly to the root zone of young trees. Micro-irrigation is particularly suited to young trees because it wets a larger area of soil than does the drip system, encouraging better root growth . Source: http://pubs.caes.uga.edu/caespubs/pubcd/B1314/B1314.htm |
