Question

pine tree   Hello:
I lived in SF bay area CA, i have 3 foothill pine in my front yard, about 50'ft. one of the pine tree needles is gradually turning yellow and then brown, over half of the tree is already brown. And the bottom of the tree trunk has whiteish-yellowish substance squeezing out of the hole. When its dried, it looks like a bumpy rock. What can I do to help the tree?? thank you
min

Answer
Min:

If this whitish stuff looks like a liquid coming from the bark on the trunk, this may be resin.  Resin is produced by the tree in response to wounding.  Often, insects are to blame, especially a variety of bark beetles.  These boring insects get into the wood, resulting in a decline. Once they get into the tree, it is virtually impossible to get all of them. Brown/yellowing needles can be a common symptom of decline. Resin will have a strong odor of pine is is very thick and sticky.  

From your description, I suspect that the amount of browning may indicate a terminal condition for the tree.  Removal may be your best option.  Ultimately, the tree can become weakened and fail during a storm, resulting in personal or property damage.  You may wish to contact an arborist in your area to give you an accurate diagnosis of the source of the decline.  These tree experts are trained to recognize all sorts of tree problems and they can give you a "house call" to see the tree "in person".

Regards
Steve