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Question from Will, Draper, UT (received 5/7/20) -

I have a mature long needled pine tree in my back yard. It is losing needles and appears less foliated than normal. It has large pustules of sappy material with what appears to be insect larvae in in several locations on the trunk and branch junctures. I assume it is a beetle infestation of some type.
Can you recommend a treatment and an applicator if it requires a professional license to treat it. The local IFA recommended a soil drench treatment of insecticide, but I feel like an injection treatment might be necessary.

Answer from Ryan Davis, Arthropod Diagnostician, Utah Plant Pest Diagnostic Lab (sent 5/8/20) -

Two things about these photos.

1. I am thinking that the brown needles are just old needles that haven't dropped yet. They died just due to the trees physiology and that is very common in the fall.
2. The resin masses on the tree are located around pruning wounds and are large. My guess is that these masses are from the sequoia pitch moth (SPM) and not bark beetles (Ips spp.). SPM does not often kill trees (only small diameter trees via girdling) an they are an aesthetic issue. The homeowner could choose to do nothing. We have a good fact sheet on this insect and some cultural/mechanical remedies for them, but there is no recommended insecticide treatment for these at this time. 

Best of luck