“I have a number of pine trees in my yard. Last year I had a number of trees that dropped new growth, this happened in the fall and winter. This year a larger number of the trees dropped the new growth. It looked like a green carpet. under the trees. The weather was dry warm and the winter was colder than usual. This year was quite warm and the winter was warmer than usual, stayed in the 20deg. Also, we had heavy snow. Also higher wind both years. Is there a problem with the weather or something else? The new candles are falling. All the candles are falling, it looks like a carpet. They are falling in the fall and winter. I’m really not sure what kind of pine they are. The pines did drop some needles in 2019, too.” Question from Raymond of Holt, Michigan
Answer: If the fresh, new candles on your pines are falling to the ground green, then it is likely that insect pests are at work, though some environmental conditions can also cause needle drop. I will cover a few possible answers for you, but without knowing what species of pines you have, and without seeing images of the damage, I cannot provide a definitive answer. I recommend that you follow up with your local extension agent at Michigan State University. Extension agents are paid to help state residents with garden and landscape problems. Yours sounds serious! (Click here to see your local agents.)
Pine Defoliating Pests in Michigan
Pine Sawflies: These nasty pests defoliate the older green needles of pines in summer. (Click here to learn more about their management.)
Pine Shoot-Tip Beetles: The damage caused by these black beetles is typically shoot-tip and branch injury. (Click here to learn more.)
Pine Tip Moths: These moths cause new growth in pines to die in summer. (Click here to learn more.)
For a detailed list of more problems that can assail pines, I recommend that you read The Christmas Tree Pest Manual (2014). It is a super resource.
I hope that you get the help that you need for your trees this season!
Black Gold Horticulturist