I have been noticing the strangest illness and am worried for one of my favorite trees. Many of its leaves get a line accross the tip of the leaf. The end of the leaf then turns yellow, then gray and curls and dies off. Meanwhile, believe it or not, 2/3rds of the leaf looks pretty good and keeps functioning. I do not see any bugs, even with a magnifying glass. I believe conditions are optimal (temp.70-80, humidifier running, bright window as well as hanging fl.lights), but this is progressing and I feel that the tree is struggling now. Why would this perfect line develop and, seemingly, circulation to the end of each leaf has stopped
Please help! So grateful.