Issue: August 16, 1999

Slowly dying pinyon

Question:

My pinyon is dying. I have had it for only a couple of years and it has looked good until now. What is wrong?

Answer:

There are several things that could be responsible for the decline of your tree. In discussing your problems with Bob Cain, NMSU Extension Service Forest Entomologist, he said he thought that insects and diseases were not the problem. He said that many problems in transplanted pinyon during the establishment period are due to the size and condition of rootball at the time the tree is transplanted.

Problems are often caused by failure to remove the material enclosing the rootball at the time of transplanting. The chicken wire and burlap that enclose the root ball are necessary for transporting the tree from forest to landscape, but are detrimental when not removed once the tree is placed into the planting hole. It is ok if some of the material remains under the rootball, but remove it from the sides so that the lateral root system is free to develop without interference. To prevent damage to the rootball, don't remove these materials while the plant is above grade, wait until the plant is in the hole. Removing the protective root coverings before placing the tree in the planting hole increases the risk of "breaking" the rootball and killing the tree.

Another problem is due to the fact that transplanted trees are often too old when dug from the forest. Tree size is not always proportional to tree age, but the proportion of active absorbing roots in the rootball is. Old trees loose too many roots in the transplanting process and are not able to redevelop an adequate root system.

Bob Cain also pointed out that the trees that die are often those which have been growing very well. This is because the owner has overstimulated top growth with excess water and fertilizer. With this rapid top growth the tree looks healthy, but the top may become larger than the root system can support in the winter. In the winter, the leaves remain on the tree and the tree needs water. At this time water is not easily provided to the top by the root system. If there is an imbalance between top and bottom, it appears following a warm, dry winter such as the one which we have just experienced. In this situation, it is the kindness of the tree owner which has caused the problem.

Bob closed with the comment, "mulch, mulch, mulch". Mulching newly planted trees helps with tree establishment, maintaining uniform soil moisture and soil temperature.