Some similarities to Cladonia mitis, another Reindeer Lichen and to Cladonia arbuscula where the bifurcations are usually at an angle of less than 120° and the branches slightly curving the same way.

Distinguishing Feature : A mass of architectural, stubby, light-grey-green branches set at 120° resembling Reindeer antlers. Free roaming, no roots. Un-like similar looking Cladonia species, portentosa does not have branches that eventually veer off to one side near the tips. Note also the colour of the tips.

USNIC ACID - A LICHEN ACID Ultraviolet radiation (UV-B) induces the formation of Usnic Acid in Cladonia Portentosa, which is thought to protect the lichen from UV-B. Usnic Acid is a bitter and yellowish-green pigment thought to only occur in lichens, but now also found in hops. Usnic acid is one of the very many so-called Lichen Acids found in Lichens (and very few other plants). It was first discovered in Usnea, a Genus of much branched lichen that hangs from trees. It is highly effective against gram positive bacteria such as those which cause tuberculosis (mycobacterium tuberculosis), food poisoning (staphylococcus), enteritis (enterococcus faecalis and faecium) and pneumonia (pneumonococcus) as well as being an anti-ptotozoan, anti-viral, anti-inflammatory and an analgesic. It is used as a preservative in cosmetics, toothpaste, sun-screen lotions, hair shampoos, deodorants and face creams. Despite it being on the suspect list, usnic acid has also been taken internally and un-officially to reduce weight, although its effectiveness is open to question. It is thought to damage the liver. It has been used in Chinese and North American Indian medicine for many years. Usnic Acid has been found to exhibit anti-biotic properties, and may explain why lichens were once used in baby nappies in New Zealand. Usnic Acid has a rather unique spectral reflectance, which makes it especially suitable for the remote sensing of lichens containing it by satellite. Norwegian scientists have charted the decline of lichen heaths caused by metal smelting; and the subsequent ascendance as metallic emissions decrease. Usnic Acid has many chemical similarities to other Lichen Acids, such as Stictic Acid, which is found in Usnea flammea.

Cladonia Portentosa is a light greyish green, with rounded branches which are bifurcated fractally several times, with branches symmetrically spaced 120° apart producing a 3D space-filling structure. It has a stubby architectural appearance, reminiscent of a miniature bilbao tree. The branches are hollow. In Canada it is known as Reindeer Moss, not only because it looks similar to reindeer antlers, but because Caribou (known in Europe as Reindeer) eat it. Other similar Reindeer Lichens are Cladonia mitis and Cladonia arbuscula.

Crotal takes up to five years to grow, but lasts a long time. It grows on grassland on wet acidic upland grassland. The author has also seen it covering the upper parts of The Lawley, a hill near Caer Caradoc in Shropshire, where it was blowing about rolling low on the grass by the high wind.

Even though its normal habitat is upland bogs and grassland, it dries readily in low relative humidity conditions for it has no roots to keep it moist, and without water storage tissues its moisture retention capabilities are very limited. Crotal is highly flammable when desiccated and is decimated by forest or moorland fires when it will take five years to recover.

In 1986 after the Chernoble nuclear reactor explosion, reindeer lichens such as this absorbed high concentrations of radionuclides, especially the more soluble and volatile ones such as caesium-137, which has a half-life of 30.1 years. It decays into the innocuous barium-137 with the emission of anti-neutrinos (which are harmless), beta particles and gamma rays. Accidental ingestion of caesium-137 can be treated with Prussian Blue, Iron hexa-cyanoferrate, Fe(CN)₆, which forms a complex with caesium, rendering it immobile and hastening its excretion from the body.

Because reindeer feed on these lichens, the radioactively-poisoned reindeer lichens contaminated the meat of reindeer, rendering them inedible and un-saleable by the indigenous folk of the area, the Sami. The Sami lost their primary source of both food and livelihood, and their future is still under threat, barely one half-life period of time having elapsed since the Chernobyl accident. It will require a period of about ten half-lives (300 years) before the extensive radioactive contamination has fallen to acceptable levels. ANY TEXT GOES HERE