Fruits & Nuts - Pecan
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  (January) I have some pecan trees that are about 60 feet tall. The past three years they have been invaded with worms. The trees are loaded with beautiful pecans, but almost all have worm holes in them. The trees are here on my farm and I have not been able to take care of them due to illness. I have help now, but need to know what steps to take. My son has a jet sprayer that reaches real high. Sure need to know how to tackle this job.

  Commercial pecan producers follow a rigorous spray schedule to keep their pecans free of insects and diseases. I typically tell home gardeners with pecan trees, to consider them shade trees, and if you get quality nuts, that is a bonus. Pecan trees can grow quite large, which can make spraying a huge job. You can get a copy of a pecan spray schedule from your local county extension office, but be aware, that thorough coverage is needed, and you will need to spray probably 8 to15 times a year, depending on the season.

  (October) I would like to plant a pecan tree. Can you give me any pointers?

  Keep in mind that to produce quality pecans you need to follow a regular spray schedule. Typically mature pecan trees are so tall that it is hard for home gardeners to get thorough coverage. You also need two different varieties for cross pollination, and it can be 7 to 10 years before they begin bearing. For home gardeners I tell them to consider pecan trees a shade tree, and if they get quality nuts (and the squirrels don't beat you to them) that is a bonus.

  I have tried grafting nut trees for two years, with no success. Several of them lived for a little while, but eventually died. If you have any current information concerning this, it would be helpful.

  Grafting is a tricky business, which breeds more success, the more you do it. I have been to commercial nurseries where they graft by the thousands with almost 100% success, but they do it on a regular basis. Your local county extension office has a good fact sheet on grafting, giving you illustrations as well as information. Make sure you match the size of the graft wood with the scion wood, and always make a few extra grafts. The best time for grafting nut trees is April, when the bark is slipping.

  My pecan tree is very sick. It has knotty growths all over it. Could you please advise what is wrong with it and what can be done? This is the first year the tree has ever had blooms and it is nine or ten years old. 

  Your tree has a very common problem this year called phylloxera gall. Three species of phylloxera are pecan pests, but only the Pecan Phylloxera causes economic damage in certain years. The pecan leaf phylloxera and the southern pecan leaf phylloxera feed primarily on the foliage, whereas the PP attacks the foliage, shoots and fruit and is therefore the most damaging.  Phylloxera are small, aphid_like insect that are rarely seen, but the galls it produces are prominent and easily noticed. Severe infestations cause malformed, weakened shoots that finally die; such infestations can destroy entire limbs. The insect overwinters as eggs which are in protected places on the branches of pecan trees. Soon after budbreak, the eggs hatch and the young insects migrate to opening buds or leaf tissue to feed on expanding new growth. Feeding stimulates the development of galls, or knotty growths. Inside the gall, eggs are laid and hatched, with the resulting nymphs remaining inside until they mature. In late June or early July, the galls split open and the mature nymphs emerge. Eggs are laid on protected parts of the trees, and wait for next spring. Usually this is more a nuisance than deadly, and timing is critical for control. The easiest method to reduce damage, is to saturate as much of the trunk and low limbs with a dormant or horticultural oil prior to bud break in the spring.

  I read an article you wrote, where you sprayed pecan trees with a dormant oil to prevent nodules where the pecans were supposed to be. The article didn’t state when to spray the pecan tree. Can you please advise me concerning this? I would also like to know what you recommend for other insects that infest pecans and when to spray for these.

  The dormant oil spray was trunk-directed as the tree broke dormancy it in February or early March. This is to help prevent phylloxera, a gall producing insect. Your local county extension office should have a complete spray schedule for pecans. There are numerous insects and diseases that attack pecans, and since the trees grow so large, it can be hard to spray for the average homeowner.

  Enclosed are leaves from my pecan tree. The pecan trees seem infested with some type of eggs, I think. I have noticed insects similar to wasps in the foliage for the second year. The trees are young. If you have time, please look at the leaves and tell me what to do.

  Your pecan tree is suffering from a common pecan problem called phylloxera. When the insects feed on the tree as the leaves unfurl, it causes a gall to form. These galls range in size from a small pea to larger. If you were to cut into the gall early in the season, you would notice tiny gnat like insects inside. By now, they have probably exited the galls. They look worse than they are. On younger trees, control is easier, but damage to the tree is a possibility from the insects. Spray as much of the tree as you can reach with a dormant oil in late February to early March ( as the leaves are beginning to bud out). This should kill any overwintering insects as they emerge. Hopefully, this can control your problem.

  We recently moved to a house with two pecan trees. They were loaded with pecans, but they all fell off around September, before they matured. I would like to know why they fell off early. Any suggestions on what we should do to prevent this next year?

  Several things can cause pecans to shed early. First, consider how hot and dry it was in August and September this past year. If there was no supplemental watering done, that could be a factor. Then, there are numerous insects and diseases which can attack pecans if a complete spray schedule is not followed. Incidentally, we really don’t recommend spray schedules for home gardeners on pecans. The trees grow too large for thorough coverage to be possible. That is why we say pecan trees should be considered shade trees for the homeowner, and if you get quality nuts (and the squirrels don’t beat you to them) that’s an added bonus of the tree.

  My need help. When should I trim them? They have lost some limbs due to heavy loads of pecans and wind. The trees are about thirty years old.

  Prune the pecans any time from now until they begin to leaf out in the spring. I am sure you will be hiring someone to do this work, so have in mind what you want done. Probably, one of the best things to do, would be to thin out some of the branches, and then prune some of the longer ones back to give stability. Never top a tree. Make sure the cuts are made clean and smooth, and don’t use any type of wound dressing.

  We have some wild pecans growing here that are bitter, or that have black rotten spots on the kernel. Is this an immune systems problem of the trees that come be corrected with trace mineral supplements?

  The problem is not nutritional, but an insect. Stink bugs attack the forming pecans and pierce the outer soft shell when it is forming. They leave behind small specks of basically saliva, which causes tiny bitter black spots on the nuts. If it can be cut out, the nuts would still be edible. They can be controlled during the growing season with an insecticide spray schedule, but pecan trees produce such large trees, that it is hard to get thorough spray coverage with home sprayers.

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