I have grown some red pines from seedlings. Last year I transferred them to 5-gallon pots and left them outside all winter. All the under branches have now turned reddish brown, but the tops appear good. Is there anything I can do to restore them back to health?
Red Pine Trees
Try steel shavings, I have pine trees not red pines and my lower branches were turning reddish brown. My husband is a machinist and brought home some steel shavings and we raked them under the tree's and it worked. You might even try steel wool