Question
QUESTION: Hi, We purchased about 16 acres in northern Tennessee about 6 years ago.  Neither my husband or myself have ever tried to grow anything before with any success.  However, most of the fruit trees, and garden plants do very well.  We have many oak trees, dogwood and other trees that are getting more and more of a white spreading mossy looking stuff on their trunks mainly, but spreading.  We have had to cut down 3 trees since we've moved in and another died last fall.  The people that have lived here for ever, say its nothing that is harming the trees, but I'm seeing the damage it does.  
What can I do to save the trees from further damage?  Looks like everyone in this area has some of the fungi? to one extent or another on some of their trees.  
I cannot find anything on the web that tells me how to get rid of it myself, and can't afford to have someone come out and treat two dozen huge trees.....help???


ANSWER: Sounds like lichens.
When lichen is wet from rain or dew, it grows actively. It also likes sunshine, and will grow well in winter after the leaves have fallen from deciduous trees and no longer block the light, or on trees with badly thinned canopies.

If you have lichen growing on the trunks or branches of your trees or shrubs, don't panic. Lichen will not actually harm your trees. That's because it takes its nourishment from the air rather than from its host. Lichens are often blamed for the decline and death of shrubs and trees because they are commonly found on dead branches and limbs. In actual fact, exposed limbs on damaged plants simply give lichens access to the sun they need for growth with little competition. There is no need to do anything, as lichen is not detrimental to the health of your plants.
The lichen will not effect the health of the tree.
If you feel you must do something and do not want the lichens on the trunk you might try this. No products are labeled for lichen control, but copper fungicides labeled for ball moss, or the home remedy of baking soda (sodium bicarbonate) for ball moss control (label pending) are detrimental. In pecan orchards, the fungicides used for scab and downy spot control reduce lichen numbers due to their effects on the fungal partners in lichens. However I would leave the lichens be.

The dying trees are not the result of the lichens.

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QUESTION: Thank you for your information.  I may be incorrect in describing the fungi.  I went out yesterday and what ever is on the tree is affecting the bark.  The bark our outer layer is actually coming off in large chunks.  The white or gray fungi is  circular and there is also a very little (compared to the gray) green moss.  I also noticed on some of the trees there is a brown fanned mushroom looking growth.  The brown seems to be in the deeper crevices.  Also, none of these fungi are attacking the crepe myrtles if that helps.  I would send a picture, but I'm not that great with the computer.   Thanks again!!!!

ANSWER: The mushroom is from a decay fungi that is in the wood of the tree. The mushroom is the fruiting body of the fungi but the fungi itself is deep in the woody part of the tree. decay fungi enter wounds on the tree and infect the woody cells causing the tree to eventually become hollow. The living part of the tree is just under the bark called the cambium layer. These fungi do not bother these cells and will not kill the tree. Trees can live as hollow trees but the strength of the tree can be weaken over time. There is nothing that can be done about the fungi in the tree but keep the tree healthy.  To increase the health of the tree I would fertilize the tree with 10-10-10 fertilizer at the rate of 1 lb of fertilizer per inch of trunk diameter scattered around the tree and water in good.

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QUESTION: Thank you,  you are awesome!!!!   Is this a free service no matter how many questions you ask?  Neither myself or my husband has much experience with trees and plants, and we have lots of both, including fruit trees (and that is a whole different dilemma)

Answer
Yes it is a free service no matter how many questions. There are other experts on plants I deal with trees and try not to get into other plants. Any question on trees I will try to answer if I can not I will say so. I answer some questions on fruit trees that deal with pests. A good source of information on growing fruit trees can be found at the local office of the State Agriculture Extension Service. Their number should be in your local phone book.