We have lived in home for 30 years. 100 + year old white oak tree is leaking sap all over deck, deck furniture, grill, deck hand rail. This has been going on since end of May. We have not had a problem in the past 30 years. The leafs are coated with a sticky like syrup. You can power wash on Saturday and the deck,etc is covered by Sunday. Why haven't we had a problem in the past and what is different this year. Back in May we had some bug stripping the leaves back to a skeleton like with just the stim and viens of the leaf left on the lower part of the white oaks, shingle oaks, and pin oaks, etc. Could this be natures way to heal the damage to the leaves.

Hi,

sap and a heavy syrup coating on leaves usually indicates the presence of some type of insects such as scale, or aphids which feed on leaves and as they feed they deposit a heavy sticky material called honeydew. Not much yo are goind to do about it on a tree as big as yours as sprays to control the insect I think are not practical. Some years may be worse than others due to populations of the insects n the tree.

I have a Black Oak that has drops of syrupy substance leaking out of the acorns that are forming, sounds like what you are experiencing?

Hi,

The biggest reason for trees to get a sticky sap like coating on them is probably due to the fact that you may have scale insects feeding on the foliage and giving off honeydew as they feed or some other type of leaf insect again giving off honeydew

I have the same issue with sap from oak tree. First time to have the problem--full grown tree too big to spray. Will this continue all summer or just a seasonal issue that will stop as suddenly as it began?

Hi,

I am guessing that yo might have either aphids of scale in the tree and as they feed they give off a sticky sap called honeydew. They won't kill the tree but they can be messy and becasue the tree is so large spraying I think is not warrenbted nor practicle so yo might ahve to put up with it for a while untill feed stops. It is also a thing that may be bad some years and not others.

This is a good explanation. We live in an oak forest in northwest Michigan and the problem is terrible this year. The hot weather especially brought it on. http://ucanr.edu/sites/oak_range/Oak_Articles_On_Line/Oak_Pest_Management/Living_Among_the_Oaks_Creates_a_Sticky_Situation/