Issue: August 23, 2008

Reasons newly planted tree may drop its leaves.

Question:

I had a tree transplanted into my landscape about a month ago. In spite of the fact that we have had a lot of rain recently, the leaves are drying and falling off. The tree was balled and burlapped when it arrived. However, I learned that it came from another town over 100 miles away. When it arrived, it was in the back of a pickup truck in which it had been transported. The burlap around the roots was dry and the top looked like the leaves had been shredded by the trip in the back of the truck. Could this be the reason that the leaves are dried and dying?

Answer:

You may have accurately identified the problem. I have seen trees in the back of trucks traveling down the highway at high speed. If the root ball is exposed it is very subject to drying out. If the leaves and twigs are not protected from the air and sun during transport, this can cause the leaves to dry and fall off. It is important to keep the roots moist and to the extent possible to protect the leaves from the high velocity, drying air during transport. However, there are other factors that could be involved.

If the root ball was "broken" so that the roots were damaged during digging, transporting, or planting you would see the symptoms you described. If the root ball was not large enough, you would observe problems. Transplanting in the summer can cause more severe transplant shock than at other seasons. Even though there have been good monsoon rains, was the water soaking in, or running off? The water must moisten the depth of the root ball or there will be symptoms of stress developed by the tree. Even with the rains, if the soil was not moistened deeply enough, you must water.

Any of these factors, including transporting the tree uncovered could cause the problems you have described. If you make sure that the soil is moistened to at least 2 feet each time it rains or supplement the rain with irrigation, you may find that your tree will survive. Unfortunately, you may not see new growth to confirm the survival of the tree until next year. Care for the tree well, irrigate to keep the soil moist, and apply a thick layer of organic mulch over the roots to conserve moisture and moderate soil temperatures. Next spring new growth will show you the real extent of the damage, if any. If there are branches that do not produce leaves next spring, you can trim them at that time.

There is hope. Do not give up on the tree now.

For more gardening information, visit the NMSU Extension publications World Wide Web site at http://www.cahe.nmsu.edu/pubs/_h.

Marisa Y. Thompson, PhD, is the Extension Horticulture Specialist, in the Department of Extension Plant Sciences at the New Mexico State University Los Lunas Agricultural Science Center, email: desertblooms@nmsu.edu, office: 505-865-7340, ext. 113.

For more gardening information, visit the NMSU Extension Horticulture page at Desert Blooms and the NMSU Horticulture Publications page.

Send gardening questions to Southwest Yard and Garden - Attn: Dr. Marisa Thompson at desertblooms@nmsu.edu, or at the Desert Blooms Facebook.

Please copy your County Extension Agent and indicate your county of residence when you submit your question!