Question
QUESTION: Hello:
Thank You for your service!

My neighbor's Oak tree is effected in the location of a once removed limb. The tree has over grown my property  line. I am terrified that the destruction made by the worms will eventually cause the tree to fail. It is a large tree that would destroy my house if it fell on it.
No one has addressed this problem until I went up to inspect the damage. The opening is sizeable and the hole is deep. I cleaned out the liquefied saw dust. The interior of the tree has the appearance of termite damage or the inside of a cave. Can I apply the Merit now or apply tree paint over the damage. I want to close up the hole with expandable closed cell foam to prevent water from entering.
Thank You

ANSWER: Sounds like two damages--an insect called a wood borer and a decay fungi.The Merit sprayed into the hole will take care of the borer. The decay fungi is in the woody section of the tree trunk and more than likely extends down into the main trunk. It entered by an old wound years ago. There is not really anything that can be done to rid the tree of the decay fungi. The living part of the tree is in the outer cells just under the bark--the woody part of the trunk is dead cells. The decay fungi is slowly decaying the woody part of the tree trunk. The effect can be a weakening of the support of the trunk but this will take many many years. Normally the decay over time will grow into the large lower limbs and these may break off during a wind storm.

The best thing to do is fertilize the tree with 10-10-10 fertilizer at a rate of 1 lb per inch of trunk diameter scattered around the tree under the branch spread and water in good. Do this now and again in the spring after leaf out.

You can close the hole with the spray expandable foam if the hole is hollow which is what I think you are describing. This will stop the water from entering the trunk and slow the decay process. Fill even with the bark surface--there is no need to use tree paint on the area.

The best thing is keep the tree healthy by the fertilizing.

---------- FOLLOW-UP ----------

QUESTION: Hi:
Thank You, for your very informative information!

Please, clarify the following. I am familiar with 10-10-10 fertilizer. I know what the drip line of a tree is.
Is the branch spread the area underneath the branches known as the tree's canopy? The tree is large so if it measures 40 plus inches around I should use 40 lbs. of fertilizer. Is it possible to fertilize just my side of the tree with out going onto my neighbor's property. Do I fertilize close to the trunk? The limb I described is the large lower limb.

Thank You,
Charlie

Answer
The drip line is what I was describing as the spread of the branches. I have had some problem with folks understanding dripline so I sometimes use spread of the branches. Same thing.

The fertilizer amount is for the trunk diameter. If the tree has a circumference of 40 inches (measurement around the tree trunk) the diameter would be 12.7 inches (the circumference divided by 3.14 or 40 divided by 3.14= 12.7 inches) So you would use 12.7 or 13 lbs of fertilizer.

You do not need to fertilize close to the trunk since the feeder roots are on the outer edge of the dripline. You can fertilize the tree on your side. I would proportion the amount out depending on the area on your side.