Wednesday, March 30, 2011

Planting container-grown pecan trees

    Planting container-grown pecan trees is becoming an increasingly popular method for establishing new pecan orchards. One of the advantages of using container-grown stock is that trees can be transplanted into the field in the spring or in the fall. In contrast, bare-root trees can only be planting in the early spring.
    The tops of container- grown trees are usually tall and straight but inside the pot, tap roots become contorted and begin circling around the bottom (top photo). To prevent circling roots from girdling the tree in the future, prune the root system before placing the tree in the planting hole. I pull the circling roots down and away from the rest of the root system to find the point where the root is growing straight down. I then prune off the circling portion of the root. You might find 3 or 4 major roots winding around the bottom of the pot. Prune off all the curled roots (bottom photo).
    Once all large circling roots are removed, the tree is ready for transplanting. When growth resumes in the field, most of the tree's energy will be concentrated on regrowing tap roots at the point of your root pruning cuts. The new tap roots will grow straight down, just like tap roots are designed to do. What we usually call transplant shock is actually just a period in the tree's life where root re-growth becomes the primary focus and new top growth is minimized.