Good morning Rob,

Thank you for submitting your questions to the UVM Extension Master Gardener Helpline.

Pine needle shedding toward the center of the tree is part of a normal cycle. The timing and number of needles dropped varies by species. White pines (Pinus strobus) show the most dramatic needle drop change. Most conifers start shedding old needles in late summer and continue into the autumn. Others shed needles primarily during the spring and summer. Yours sound like they drop in spring and fall but this not a concern if the shedding is not at the tips. Evergreen trees keep their newest needles, produced this spring, as well as their 2^nd and often the 3^rd year needles. The needles that are dropping in the interior are the oldest. As the tree grows, newer needles are always at branch ends and older needles are farther back in the crown. As needles age, they become less efficient at producing food for the tree. They also become more shaded by newer needles. For these reasons, old needles finally turn brown and drop off. This doesn't hurt the tree because several year's worth of newer needles are always there to replace the old ones.

I f your tree is losing needles at the branch tips, the young needles, this is reason for concern. Then suspect insect or disease damage. If one-third to one-fourth of the needles on the inner parts of your evergreen tree are falling off, it is a normal sign of aging.

Rake up the dead needles on the lawn if they are a thick enough layer to smother the grass or plantings where they fall but some can be left as mulch. They are acidic when they first fall but they will brown quickly and then make good mulch.

I hope this helps. Some references are listed for you below.

https://extension.purdue.edu/news/county/whitley/2022/10/evergreen-needles-dont-last-forever.html

https://extension.usu.edu/forestry/trees-cities-towns/tree-care/pine-losing-needles

On 10/23/2024 6:41 AM EDT Ask Extension wrote: