Question
QUESTION: I have 300 walnut seedlings (2 to 4 yrs old) snd the deer pruned the tops out of all of them a year ago.  They have from 3 to 6 leaders now and I want to know if I can prune all but one off of each one.  Southern Mich. and I want to grow them for logs.  I have foam cups bottom side up on each one with a sponge which I spray with home made deer repellant now, and no deer have even gone throught the planting this winter.   Thanks, Glenn

ANSWER: I would think the best thing is to let them grow taller--above where the deer can reach the terminal bud. The after the seedlings have exhibited a main trunk then prune the forks off leaving a single main stem. That way the tree can take advantage of the extra foliage to produce a good sound root system. I would wait several years and the pick the main stem and prune the others off.

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QUESTION: I have 2 acres of mostly wild cherry (maybe 40 to 50 yrs. old in So.Mich) and a year ago several of them had a jelly like substance all over the bole up to the limbs and it ran right down the hill from the bottom of the trees.  I've seen that on cherry before, but never just covering the whole trunk.  I've only seen one this year.  (I'm going to plant 100 cherry seedlings this year.)  I'm afraid of the walnut kill in Denver and in Tennessee, so I switched to cherry and have 6 or 7 more acres to go in the future and I don't want cherry if they're all going to die. Glenn

Answer
Can be an indication of an infestation of borers,a peachtree borer, and cherry trees are the primary host plant, and one of the symptoms of infestation is gobs of gum leaking from the tree.However, peachtree borer is not the only thing that will result in a plum tree experiencing bleeding gummy sap. If the gum is emerging from rather high up on the trunk, rather than from near the root crown (the favorite spot for peachtree borer infestations), the bleeding is not likely to be caused by peachtree borer.

Look at the point where the gum is exuding from the tree. Look for wood debris (frass) mixed in and around the exuding gum. The gum is coming from a hole in the bark of the tree. The hole was formed when the peachtree borer larva dug its way out to the surface. It is highly unusual for damage caused by the exiting of a peachtree borer larva to be more than one foot up from the ground. So, peachtree borer injury occurs low on the trunk, and there is frass associated with the exuding gum.

Borers attack usually because the tree is under stress. Borers can be treated with an insecticide called Onyx or Merit. This is sprayed on the effected area killing the borer under the bark.

The exuding of gum from plants in the genus Prunus, including the cherries, is so common it has been given the name gummosis. The name gummosis does not define a cause, only a response. We have seen how peachtree borer injury and simple mechanical injury can result in gummosis. There are also several infectious diseases that can result in gummosis. There are three groups of organisms that can cause cankers on cherries and result in a gummosis response. One is a bacterium in the genus Pseudomonas which causes a disease known as bacterial canker. Another is a fungus in the genus Leucostoma (Cytospora) that causes Leucostoma canker of Prunus. The third is usually called fungal gummosis and is caused by the fungus Botryosphaeria dothidea. It is not important in a practical sense to identify the specific organisms involved but, it is important from a diagnostic point of view to differentiate between insect infestation, mechanical injury, and infectious disease. In all three of the diseases listed above, the key diagnostic feature is the canker.

A canker is a necrotic (dead), often sunken lesion on a stem, branch, or twig of a plant. In the case of gum bleeding from the trunk of a cherry tree, a canker can be identified by the death of tissue immediately beneath and surrounding the point of gummosis. If you carefully scrape away the gum and probe the bark beneath, you will find the bark loose and the tissue beneath discolored. In fact, the bark at the point of gummosis may slough off easily indicating dead tissue. In most cases where a canker and its causal disease is concerned the infected tree is, or has been, under some type of environmental stress. This can be a weak root system due to poor soil conditions or drought stress.

I would guess this is the result of a previous drought and the trees will recover. Since they are this old I would do nothing and they should be ok.