Lichen on Tree Branches?

Question:

I have Lichen on my apple tree branches. It's not removable with power spray. Can a copper spray be used? The lichen is a fine feathery type on slender growth.

Allan from New Zealand

Answer:

Allan,

Unless it's really unsightly, removing lichen can sometimes cause more harm than good. If you absolutely must remove it, you can do so using a soft scrubbing brush and water or by covering the tree with a shade-cloth. Eventually the lichen will die from lack of light.

For readers who don't know, when lichen is present, it is not responsible for any decline you're seeing in your trees. These plants are non-aggressive and only colonize after trees become stressed. The slow growth of the declining plants makes it easy for them to compete. Lichen form through a symbiotic relationship between algae and fungus. The algae produce food (through photosynthesis) to feed the fungus, and the fungus collects moisture (and nutrients) for the algae.

Lichens are great environmental indicators, because they take in everything that is dissolved in the rainwater they collect. They will not grow where there are toxic elements that pollute the water, so if you have them growing in your backyard, you're probably breathing pretty clean air.

Ellen