We cut our Christmas tree this weekend and have noticed most of the branches have black dots in lines in the needles. What are these? Should we contin...
Black Dots on Pine Needles #817006
Asked November 28, 2022, 9:58 PM EST
We cut our Christmas tree this weekend and have noticed most of the branches have black dots in lines in the needles. What are these? Should we continue to keep the tree inside or should we remove it? Are there ways to rid the tree of these black dots other than wiping each needle?
This appears to be an insect (either eggs or older life stages) but we would need to see the objects a bit more clearly to be sure, and once we identify them we can then advise how to remove them, if necessary. Can you please take one or two more close-up pictures with better lighting? (Perhaps using a camera flash, or maybe the ambient light during the daytime is enough.) If the camera has trouble focusing on the objects because of their size or due to background objects, you can try to either hold a piece of white paper behind them or a ruler next to them (the fine markings on the ruler should help the camera focus at the right distance).
Thank you for the photos. Their size, shape, color, and arrangement suggests they are the eggs of the White Pine Aphid. Normally aphids give birth to live young, but they can lay eggs (especially for overwintering), plus this type of aphid is so large that their eggs will also be pretty big by aphid standards. We can't predict if they'll stay warm enough for long enough to hatch indoors, but you can pluck them off if you prefer. They won't cause any plant damage and will merely be a nuisance to remove with a vacuum if they do hatch before the tree is removed after the holiday.
This work is supported in part by New Technologies for Ag Extension grant no. 2020-41595-30123 from the USDA National Institute of Food and Agriculture. Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture.