Question
QUESTION: I have a California oak tree with white, bubbly foam coming out of the bark of the main trunk. Is this fungus or an i sect infestation?  Also, do you know how to treat it?  Thanks for your help!

P.S.  One of the main limbs has rot in it.  Is there an effective way to treat and/or seal it?  Thanks!

ANSWER: Hi there It sounds like Wetwood: Wetwood is a bacterial disease.The infection can be in a wound on the trunk surface or it can be deeper inside the trunk. In either case, bacteria
ferment the tree's sap; it seeps out and down to the ground. Sweet-eating insects (wasps, bees, yellow jackets) would obviously be attracted to the
damaged area. The infected wood is frequently discolored or appears water soaked (wet wood).

Gas (carbon dioxide) is produced by fermentation by bacteria. The gas produces pressure in the wood. This pressure forces sap from the trunk through
cracks in branch crotch unions, pruning wounds, lawn mower wounds, other injuries and occasionally unwounded bark.

This oozing is called "slime flux" and is caused by a bacterial infection inside the trunk.
There are actually two types of slime flux: 揳lcoholic攁nd 揳cidic? The acidic flux smells like vinegar. The flux is colorless to tan at first but
darkens up with exposure to the air. As fluxing continues,large areas of the bark become soaked. Many different microorganisms grow in the flux
producing a foul or alcoholic smell. Various types of insects are attracted to the slime flux. If the fluxing continues for months, leaves on
affected branches may be stunted and chlorotic.

Grass may be killed where the flux runs down the trunk onto the grass.The flow of sap is periodic; it may disappear and not reoccur or you may see it
every year.

Large mature landscape oaks have had problems with slime flux on the trunk or large exposed flare roots just above the soil line with no apparent wounds
or injuries. Sap may continue to ooze for several weeks or months, but usually it eventually stops with no treatment and no apparent damage to the tree. This slime flux may be triggered by heat, drought and other stress.

There is no treatment for the condition. The best thing to do is to wash off the trunk to discourage bugs. Mix a pint of chlorine bleach in a gallon
of water to make a final rinse. Try to maintain trees in a general good state of vigor and minimize wounds and injuries.

More damage can be done to the tree in attempting to cure wetwood than the flux will do alone.
#2 There is no way to treat or cure decay. Depending on the location and size of the limb,you may want to have it removed if there is any chance of it hitting someone.  Hope this helps,Bill

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QUESTION: thank you for the fast response, could it be scales? very nice tree would hate to lose it. thank you mark f wiegel

Answer
Here is some info on scale.You can also google. There is a ton of info on this subject.Glad to be of some help,Bill

Scale is tiny parasitic insects that adhere to plants and live off the plant抯 sap. They look like bumps and are often mistaken for a disease. Put some pressure on them to see if they squish, if so they are scale There are some 7,000 species of scale insects, varying greatly in color, shape and size, usually ranging from 1/16 - 1/8 inch.
Scale is usually divided into 2 groups: soft scale and armored scale. Soft scale is covered with a protective waxy substance and is somewhat easier to kill than armored scale, which secrete a hard shell over their bodies for cover. Mealy bugs are also part of the scale family.
Scale eggs are laid under the female抯 body. They are called crawlers when they first hatch, because the nymphs have legs at this point and crawl off to find their own spot to attach and feed. Control measures are most effective during the crawler stage.
Different species favor different plants. Plants frequently infested with scale include: Euonymus magnolia and fruit trees and shrubs
Control of Scale
?  Outdoor Plants:
o   Treat with dormant oil in late spring, just before the leaves unfurl. Scale can overwinter as nymphs or eggs tucked away in tree bark.
o   If you catch the problem early, pruning infected branches is often the easiest and surest solution.
o   Scale are preyed on by beneficial insects like soldier beetles, lady beetles and parasitic wasps.
o   An arborist can do systemic treatment or spray if warrented.
?  Indoor Plants: Remove scale by rubbing gently with a facial quality sponge dipped in rubbing alcohol. The alcohol alone should kill the scale, but the dead insects will remain on your plants and make it difficult for you to scout for new infestations. The small facial sponges, found in the cosmetic aisle, are abrasive, yet soft enough to use without scraping the plant stems.
Be sure to buy plain sponges, without cleanser or lotion in them. As always, test on a small area first, since some plants are more sensitive than others.