What’s wrong with my pine tree - Ask Extension
What is happening to my pine trees. We are loosing needles on the north side. It appears new needles are coming on the tips of the branches only. W...
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What’s wrong with my pine tree #797213
Asked June 22, 2022, 10:39 AM EDT
What is happening to my pine trees. We are loosing needles on the north side. It appears new needles are coming on the tips of the branches only. Water from our sprinkler system hits these trees on both north and south side but they only are loosing needles on the north side.
Otter Tail County Minnesota
Expert Response
There are multiple reasons why inner pine needles drop.
1. It is normal for inner older needles to drop. Those on the north side may be shaded and not get as much nutrition. See: https://forestry.usu.edu/trees-cities-towns/tree-care/pine-losing-needles
2. If there is a road on the north side and decking salts are used, needles can be affected. Usually this includes outer needles as well.
3. There a number of diseases that can affect pines and cause needle drop. The following website gives closeups of needles and ideas on what to look for. Usually signs of disease would not be limited to one side of the tree, except that needles on the north side may be weaker due to shading from the sun. See: https://apps.extension.umn.edu/garden/diagnose/plant/evergreen/pine/index.html (You will need to click on each drop down link to see the pictures.)
1. It is normal for inner older needles to drop. Those on the north side may be shaded and not get as much nutrition. See: https://forestry.usu.edu/trees-cities-towns/tree-care/pine-losing-needles
2. If there is a road on the north side and decking salts are used, needles can be affected. Usually this includes outer needles as well.
3. There a number of diseases that can affect pines and cause needle drop. The following website gives closeups of needles and ideas on what to look for. Usually signs of disease would not be limited to one side of the tree, except that needles on the north side may be weaker due to shading from the sun. See: https://apps.extension.umn.edu/garden/diagnose/plant/evergreen/pine/index.html (You will need to click on each drop down link to see the pictures.)
