What your friend was most likely referring to was painting the tree with a 1:1 mixture of water and water-based indoor latex paint. This is what I use to paint the tree trunk and branches.

Purdue Landscape Report: Slime flux (also known as wet wood) is a dark, foul-smelling and unsightly seepage of sap from tree trunks (fig. 1).The disease is not usually a serious problem but the ...

Question: We have a can of spray foam that says it can be used to fill cavities in tree trunks. There’s a hole in one of our trees where a branch was removed — it’s about waist-high. The ...