Physcia magnussonii Frey
Physcia magnussonii Frey is a lichen species that belongs to the family Physciaceae, found in the Arctic and alpine regions. The plant was first described by Helge Thorsten Lumbsch in 2008. It is known by the common name Magnusson's rim-lichen.
Appearance
Physcia magnussonii typically appears as a greenish-gray or brownish-gray crustose lichen. This species is generally small, and usually less than 5 cm wide. The surface is covered by small dark gray to black spots called pycnidia, which are the fruiting bodies of the fungal component. The lichen has a rim-like structure and is surrounded by a white prothallus.
Uses
Physcia magnussonii Frey is not used for any commercial or medicinal purposes. However, it has ecological importance because it serves as a primary food source for reindeer and caribou, which live in Arctic regions. Apart from that, the species also serves as indicators of air quality and environmental changes.
Light Requirements
Physcia magnussonii thrives well in shaded areas or places with indirect sunlight. Too much exposure in direct sunlight can damage the thalli and inhibit the growth of the plant. The plant prefers to grow in partially shaded areas, such as under the canopy of other larger plants or trees.
Temperature Requirements
The ideal temperature range for the growth of Physcia magnussonii is between 10°C to 20°C (50°F to 68°F). The plant can also tolerate colder temperatures, but growth may be slower. Temperatures that are too hot, above 25°C (77°F), can harm and kill the plant.
Soil Requirements
Physcia magnussonii is not a soil-dwelling plant, and instead grows on surfaces such as rocks, boulders, and tree trunks. However, the plant can absorb water and nutrients from the environment, including areas around soil. Therefore, a healthy soil environment around where the plant grows can also help promote its growth indirectly.
Cultivation Methods
Physcia magnussonii Frey, also known as the large bone Physcia, is an epiphytic lichen that can grow on rocks, trees, and wood. If cultivating Physcia magnussonii Frey, it is essential to provide an adequate substrate such as smooth-barked trees since the lichen is susceptible to pollution and other environmental stress.
Watering Needs
Physcia magnussonii Frey requires minimal watering and can survive on the humidity found in its natural environment. Watering the lichen directly is not advisable since it can compromise the thallus, causing damage to the structure of its hyphae cells and making it prone to infections.
Fertilization
Unlike higher plants, lichens such as Physcia magnussonii Frey do not require fertilization since they can obtain all of their required nutrients from the air, water, and minerals in the substrate where they grow. However, it is essential to provide them with a healthy substrate to ensure the lichen's growth and survival.
Pruning
Physcia magnussonii Frey does not require pruning since it is a slow-growing lichen and does not produce leaves or branches. Nonetheless, it is essential to remove any litter or debris accumulated on the substrate where the lichen grows to prevent the accumulation of moisture and the proliferation of opportunistic pathogens.
Propagation of Physcia magnussonii Frey
Physcia magnussonii Frey is a lichen species that can be propagated through several methods. The most common propagation method is through the division of the thallus.
Division of the Thallus
The thallus of the Physcia magnussonii Frey can be divided into smaller pieces, which can then be attached to a substrate. Thallus division can be done manually by carefully pulling apart the thallus pieces or using a scalpel. It is important to make sure that each piece contains both the fungal and algal components to ensure successful propagation.
After the thallus is divided, the small pieces are attached to a substrate such as a rock or bark using a non-toxic glue. The substrate should be placed in a shaded area to allow the lichen to grow and establish itself. It is important to maintain a suitable level of moisture in the substrate to aid the growth of the lichen.
Propagation Using Soredia
Another method of propagation for Physcia magnussonii Frey is using soredia. Soredia are small reproductive structures that contain both the fungal and algal components of the lichen. They can be found on the surface of the thallus and can be used to produce new lichens.
To propagate the lichen using soredia, the soredia are collected and sprinkled onto a suitable substrate, such as a rock or bark. The substrate is then placed in a shaded area and maintained with a suitable level of moisture to allow the soredia to establish and grow into new lichens.
Disease Management
Physcia magnussonii Frey is generally considered a highly resistant lichen species, but it is still susceptible to diseases. The most common fungus that affects Physcia magnussonii Frey is Opegrapha spp. This fungus can cause dying off of the thallus, malformed branches, spots on the thallus, and many other symptoms. To manage this disease, it is best to remove any affected parts of the lichen and dispose of them properly. It is also helpful to keep the lichen healthy by providing sufficient light, water, and nutrients.
Pest Management
Physcia magnussonii Frey may become a host to various pests that can harm it, such as mites, lice, and scale insects. Pests can damage the thallus by feeding on it, resulting in discoloration, deformation of branches, and even death of the entire lichen. To manage pest infestations, it is recommended to isolate affected lichens to prevent spreading. Chemical control is not advised as it could harm the lichen. Instead, manually remove pests with a soft brush or water sprays regularly.
