I live in Portland, Oregon and have many Douglas Fir trees on my property. I have a Douglas Fir that is flowing sap year round. Also, on other Douglas Firs, the bark is opening up so that you see the trunk inside. Is this something that I should worry about?
Though sap oozing from a tree can be normal it also can indicate a more serious issue.
Here are a few links for you.
You may want to consult an arborist t determine the health of the trees.