yellow needles on white pine tree

Asked September 22, 2016, 5:22 PM EDT

We have had this white pine tree for about 3 years and in the past week we have noticed that the needles have been turning yellow. My husband also noticed that our neighbors behind us, who have a pool, had pulled back their cover and pool water drained into our yard at the site of the tree but we don't see any yellowing of the grass (the grass is further away but was hit with the pool water). We appreciate any insight on this. Thank you, Rita Sicora PS. this site is not allowing me to upload a picture.

Washington County Minnesota white pine iron chlorosis needle drop

1 Response

Approximately every 3 years evergreens shed the maximum number of old needles. This is probably what is going on with your tree.
http://web.extension.illinois.edu/state/newsdetail.cfm?NewsID=26364
The other explanation could be chlorosis. White pine require acidic soil or their needles turn yellow.
http://forestry.usu.edu/htm/city-and-town/tree-care/preventing-and-treating-iron-chlorosis-in-trees-...
http://www.mortonarb.org/trees-plants/tree-and-plant-advice/horticulture-care/chlorosis