By Dunscombe
Hampshire,
United Kingdom 
hello, i have a small salix tree in my front garden. it has been there for 7 years nearly. this year i noticed that all the branches have some sort of algae on them. a friend said this hapens when its dry and warm. he said that there was something i could spray on that would bring it back to normal. can you help and do you know what that might be?
4 Aug, 2010
Answers
As bamboo says if its lichen it wont hurt. It can mean that you have good clean air around the plant though.
4 Aug, 2010
It's probably lichen, I imagine - you could try cleaning it off with a solution of insecticidal soap and water, but otherwise, I'd think a fungicide spray would see it off. It won't harm the plant, though if there's a lot of it, I understand you may find it unsightly.
4 Aug, 2010