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Lichens,Algae,and Moss.


By drc726


I was reminded on my garden visit yesterday that Goy often gets asked about lichen on trees and shrubs.
Lichens may be flat, leafy, or branched and hairlike. All three forms occur on tree bark as well as on rocks, soil. The colour ranges from white/gray, red, green, yellow, and black.
Algae can be seen on tree trunks and leaves of evergreen trees and shrubs, as a green, powdery deposit. It is not unattractive on trunks but can make leaves dull and unsightly. The alga Trentepohlia is seen as a vivid orange powdery deposit on tree trunks and branches.
Various mosses can grow on the trunks or branches of trees and shrubs. These mosses may form large, coarse, loose, green or yellowish-green tufts, densely matted tufts, or compact green cushions.
Lichens and algae are often mistaken for a fungal disease but, they do not harm plants on which they grow. The fact that lichens grow rapidly when exposed to full sunlight may explain their profusion on dead trees. Lichens on trees indicates that the air nearby is relatively pure as most lichens will not grow in a polluted atmosphere so maybe seen more in rural areas.
Lichens, like other plants, need water and minerals in order to grow, those growing on trees get water and minerals from the air. When a lichen is wet it grows actively, but stops growing when it dries out in the summer and lies dormant until the next rain when starts it growing again. Lichens have also been used in making dyes and perfumes

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~ brilliant blog Denise~ there has just been a survey sponsored by the National History Musuem of lichens see below

Help OPAL scientists with important research, learn new skills, have fun

OPAL is running five surveys across England to learn more about the state of our environment, and we’d like everyone to get involved.

Surveys exploring the health of our soils, air and water are running now - see below for details. Future surveys will look at our biodiversity and climate.

All ages and abilities can take part and your contribution will be important in helping scientists build up a picture of England's natural environment. We'll provide easy-to-follow survey instructions and all the support you need.

Water survey - join in now

How healthy is your local pond or lake? The animals that live there can give important clues about the water quality. Record what you discover and contribute to valuable national research.
More information and how to take part

Completed our survey? Enter your findings online

Air survey - join in now
Sycamore leaf with tar spot

Discover what lichens can tell us about air pollution. Record tar spot on sycamore leaves to learn about air quality near you.
More information and how to take part

Completed our survey? Enter your findings online

Soil and earthworm survey - join in now

Discover more about earthworms and the soils they live in. Contribute to important scientific research and help update our national record on earthworm distribution.
More information and how to take part

Completed our survey? Enter your findings online

Upcoming surveys

Biodiversity survey

Starts: September 2010

Survey details to be announced.

Climate survey

Starts: March 2011

16 May, 2010


That sound of interest Arlene will have a look.

16 May, 2010


How very interesting, I have lichen growing all over my magnolia so I presume the air quality must be good which is reassuring. :o)

16 May, 2010


Now there's a funny thing - yesterday I took a photo of a tree with lichens on it's branches ! I'll upload it tomorrow. It was a willow growing by a river.

16 May, 2010


Premonition Hywel?

16 May, 2010


It must have been :o) Such things happen too often for them to be mere coincidences.

16 May, 2010

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