Blue Stain vs Pine Beetle Kill

Asked September 6, 2016, 9:13 PM EDT

I have (had) what looked like a Scotch Pine in my front yard (I live in Briargate). Last spring, near the base, it started excreting what looked like white sap....very very very thick all around the base (see attached photo). By spring this year, all the needles on the tree had turned brown and the tree was dead (all branches snapped off with no sap in them). Today, I removed the tree, and saved it to figure out what caused it to die. Was it pine beetle, or perhaps something else? Yes, it does have the typical blue staining inside.
FYI: I own 5 acres of land near Estes Park that has been decimated by the pine beetle (all Ponderosas), but this took me by surprise.

Can you help please?

El Paso County Colorado trees and shrubs

1 Response

I assumed you are correct that the tree was Scotch pine. So, I went looking for info about the symptoms you described. The blue stain would be a symptom of mountain pine beetle - see link below. But oozing is not a symptom of pine beetle. Oozing would be a symptom of pinon pitch mass borer. See links below.
If you wish to replace this tree I am also providing a link to a list of recommended trees for the front range.
Mountain Pine Beetle - http://extension.colostate.edu/topic-areas/insects/mountain-pine-beetle-5-528/
Pitch Mass Borer - http://www.ext.colostate.edu/ptlk/1456.html
Pitch Mass Borer - http://www.colostate.edu/Dept/CoopExt/4DMG/Pests/pinyon.htm
Tree Recommendation List - http://extension.colostate.edu/docs/pubs/garden/treereclist.pdf