I mentioned before about lichen not returning to the scene once it has been killed off from the initial cleaning. Well,..I seen more jobs this past season that I was previously at 4-5 years ago I guess,..and the lichen is not returning,..the moss does return,..but still wondering why the lichen doesn't come back?
Anyone else notice this strange phenomenon?
Jeff
BlueRidge said
Dec 17, 2019
I have not looked Jeff. I actually never thought about it. The roofs we have gone back to are roofs I personally treated and now they are treated by one of the crews so I seldom see them. Now I will remember to put a question about lichen on their sheets.
My only guess is that lichen must take a much longer time to grow once the spores are happily eating away at the algae. Time for research.
Drum roll please... Some good information and a short read. Lichen Growth
"Like all living things lichens need nutrients and energy to grow. Nutrients they obtain from the air (including dust), water and some from the substrate they are growing on. Energy they obtain through photosynthesis, which is the role of the algal partner. They can also be incidentally fertilized by bird and insect dung."
"They grow very slowly, some species more slowly than others. Rates of growth can vary from 0.5mm per year to 500mm per year. Their slow growth rate equates with their long life."
"Lichens live all across the world, in Antarctica they can be found living just below the surface of rocks, in deserts, providing there is a permanent substrate they can be found surviving the hottest sun, they can also be found in rock pools on the sea shore and on the roofs of our buildings."
DirtyRoofcom said
Dec 17, 2019
I frequently check back on roofs when I'm in the area (more for my own knowledge and curiosity). I have noticed:
Lichen is the most resilient of the 3. The only times I've ever had to go back and do touchups is because of lichen and it's usually the really large ones (3-4"+). The roof will be spotless w the exception of a few lichen hanging on.
Algae comes back first. Ive seen algae come back under 2 years but its generally only in areas with heavy tree growth near the house or tall mature trees.
I've seen moss come back only after many years and under Oak trees.
Cant say I've seen lichen grow back on any roof I've done.
I mentioned before about lichen not returning to the scene once it has been killed off from the initial cleaning. Well,..I seen more jobs this past season that I was previously at 4-5 years ago I guess,..and the lichen is not returning,..the moss does return,..but still wondering why the lichen doesn't come back?
Anyone else notice this strange phenomenon?
Jeff
I have not looked Jeff. I actually never thought about it. The roofs we have gone back to are roofs I personally treated and now they are treated by one of the crews so I seldom see them. Now I will remember to put a question about lichen on their sheets.
My only guess is that lichen must take a much longer time to grow once the spores are happily eating away at the algae. Time for research.
Drum roll please... Some good information and a short read. Lichen Growth
"Like all living things lichens need nutrients and energy to grow. Nutrients they obtain from the air (including dust), water and some from the substrate they are growing on. Energy they obtain through photosynthesis, which is the role of the algal partner. They can also be incidentally fertilized by bird and insect dung."
"They grow very slowly, some species more slowly than others. Rates of growth can vary from 0.5mm per year to 500mm per year. Their slow growth rate equates with their long life."
"Lichens live all across the world, in Antarctica they can be found living just below the surface of rocks, in deserts, providing there is a permanent substrate they can be found surviving the hottest sun, they can also be found in rock pools on the sea shore and on the roofs of our buildings."
I frequently check back on roofs when I'm in the area (more for my own knowledge and curiosity). I have noticed:
Lichen is the most resilient of the 3. The only times I've ever had to go back and do touchups is because of lichen and it's usually the really large ones (3-4"+). The roof will be spotless w the exception of a few lichen hanging on.
Algae comes back first. Ive seen algae come back under 2 years but its generally only in areas with heavy tree growth near the house or tall mature trees.
I've seen moss come back only after many years and under Oak trees.
Cant say I've seen lichen grow back on any roof I've done.