Hello,
That was a good idea to check the tips for insects. If the insect is not present, examine the damaged terminal growth to see if there is evidence of the internal tunneling typical of most tip moth injuries.
Insecticides are an effective way to treat the moth but timing of the insecticide is important. Pine tip moth can affect many types of pine trees so the type of pine will determine when to spray. The attached fact sheet will talk you through your options and the timing should you wish to hire an aborist to treat it.

https://extension.colostate.edu/topic-areas/insects/pine-tip-moths-5-529/

Thanks for you response.

It's a pinyon pine tree. I have cut off and examined 15 tips and can't find any larvae.

If they are on the ground as pupa, it doesn't seem like spraying would help. The info page you sent mentions several possible types of infestation, and I don't know how to determine which it is.

If there are no visible larvae, it suggests they have fallen off, become pupa, and are no longer eating. 

In which case, is there a spray FOR NOW, or should we just wait till the Spring?

Thanks for your help.

J Mattox

Hello,
Without evidence such as catepillars, moths, pitch, or tunnels or larvae near the needle tips, which would confirm the insect infestation, a second opinion from another arborist might be a good idea. 

Since insecticide wasn't used in May to control larvae, later treatments could still be effective at killing larvae moving from buds to developing shoots. Midsummer applications coinciding with egg laying in late July appear to be most appropriate for pitch nodule moth control. Again, timing depends on which moth is attacking your tree.

IF you would like us to do a diagnosis of your infected pine, you would need to bring a sample of infected needles on a branch to our extension office at 9595 NElson Rd. Longmont between 8-4:30 Monday through Friday.
-Rita CMG with CSU Extension