Foliose lichen

[2] Foliose lichens are attached to their substrate either by hyphae extending from the cortex or medulla, or by root-like structures called rhizines.

[3] The latter, which are found only in foliose lichens, come in a variety of shapes, the specifics of which can aid in species identification.

Foliose lichens are extremely sensitive to sulphur dioxide, which is a by-product of atmospheric pollution.

By-products of this weathering are poorly ordered iron oxides and amorphous alumino-silica gels, the neoformation of crystalline metal oxalates and secondary clay minerals.

[8] These combined processes – of chemical and physical weathering – also serve to deteriorate asphalt shingles, with foliose lichen byproducts dissolving the limestone (calcium carbonate) used as filler and their rhizoids expanding cracks which develop in the shingles over time.

In order for lichen reproduction to take place the fungal partner must produce millions of germinating spores which fuse to form a zygote that must then also find a compatible photobiont.

Foliose lichen use isidia which are cylindrical finger like protuberances from the upper cortex in which algal and fungal tissue is incorporated into.

Flavoparmelia caperata , a species of foliose lichen, on a branch of a tree
Cross section diagram of foliose lichen with layers: 1. Thick layers of hyphae , called the cortex 2. Green algae 3. Loosely packed hyphae 4. Anchoring hyphae called rhizines .