Piñon pine disease - Ask Extension
On the upper part tree the needles on the end of the branch died. On larger branches with dead needles there are nodules with sap like liquid. Ap...
Knowledgebase
Piñon pine disease #843514
Asked July 31, 2023, 4:14 PM EDT
On the upper part tree the needles on the end of the branch died. On larger branches with dead needles there are nodules with sap like liquid. Appeared mid July.
Larimer County Colorado
Expert Response
Hi Cathy,
This looks like the pinon pine tip moth. We have a publication on it: https://extension.colostate.edu/topic-areas/insects/pine-tip-moths-5-529/
Usually it is not something that needs to be treated and doesn't affect the overall health of the tree, but if you want to prevent it from happening next year, you'll need to apply an insecticide during tip elongation in spring (usually May-ish). According to our fact sheet:
Treatment timing for the pinyon tip moth is less well known. Thorough insecticide treatment in May should be effective if applied to new growth before overwintering Dioryctria larvae enter buds. Somewhat later treatments can 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.
This looks like the pinon pine tip moth. We have a publication on it: https://extension.colostate.edu/topic-areas/insects/pine-tip-moths-5-529/
Usually it is not something that needs to be treated and doesn't affect the overall health of the tree, but if you want to prevent it from happening next year, you'll need to apply an insecticide during tip elongation in spring (usually May-ish). According to our fact sheet:
Treatment timing for the pinyon tip moth is less well known. Thorough insecticide treatment in May should be effective if applied to new growth before overwintering Dioryctria larvae enter buds. Somewhat later treatments can 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.
So it could be beneficial to do treatment now?
Hi Cathy,
No, treatment will not do anything to prevent this from happening next year. You'll need to time treatment when the larvae are active, which is usually in May. I would contact a tree care company if you wish to treat. However, while the damage looks bad, it rarely causes harm to the overall health of the tree.
No, treatment will not do anything to prevent this from happening next year. You'll need to time treatment when the larvae are active, which is usually in May. I would contact a tree care company if you wish to treat. However, while the damage looks bad, it rarely causes harm to the overall health of the tree.
Thank you for the clarification.
