I don't mind the algre in the tree or maybe it fungus. I have had the city out twice. Don't want to kill the tree just the algre or fungus on the tree so it won't fall and grow on my red rocks. It's the city's tree in my yard. City said get Horticultural Spray Oil-not working on rocks. Betty Mun |
Horticutural oil should suffocate the lichen. If that's not working, try a lime/sulfur (bordeaux spray) which is sold as a dormant spray for fruit trees. It will kill the lichen, which will eventually fall off the tree. These products may nott work on the rocks, though. The lime/sulfur won't hurt the rocks, so it's worth a try. If the rocks are small you can rake them to improve air circulation. If the rocks are large and stable, you may be able to power wash them to remove the lichen. Hope this information helps! |