Overview
Melanelia subargentifera (Nyl.) Essl. is a lichenized fungus that belongs to the family Parmeliaceae. It is also commonly known as Rock Greenshield Lichen. This species is widely distributed in North America, Europe, and Asia, where it can be found growing on rocks, cliffs, and trees.
Appearance and Identification
Melanelia subargentifera is a foliose lichen that forms large rosettes with a diameter of up to 15 cm. It has a distinct silver-grey coloration, although the color may vary depending on the environment it is growing in. The upper surface is smooth, while the lower surface is black and has many small rhizines that help to anchor the lichen to the substrate. The thallus (body) of the lichen is generally less than 5 mm thick, and the lobes are usually tightly overlapping.
In terms of identifying features, Melanelia subargentifera has a medulla that is K+ yellow and C-. It also has a cortex that is composed of small, round cells.
Uses
In traditional medicine, Melanelia subargentifera has been used to treat a number of ailments including sore throat, coughs, and digestive problems. The lichen contains a compound known as usnic acid, which has been found to have anti-inflammatory, antibacterial, and antiviral properties.
Melanelia subargentifera is also useful as a bioindicator of environmental pollution, particularly heavy metal pollution. The lichen absorbs pollutants from the air and water, and changes in the lichen's growth and pigmentation can indicate the level of pollution in the environment.
Finally, Melanelia subargentifera has aesthetic value and can be used as a decorative element in gardens and terrariums.
Light Requirements:
Melanelia subargentifera prefers shady and moist environments like forests, streams, and wetlands that support growth of other mosses and lichens. They grow well in partial shade, or areas with filtered light. Direct sunlight should be avoided as it can dry out the lichen and halt growth.
Temperature Requirements:
The ideal temperature range for Melanelia subargentifera is between 12 °C to 16 °C. The lichen is adapted to withstand cold temperatures and can survive in areas where the temperature drops to -30°C.
Soil Requirements:
Melanelia subargentifera grows mostly on acidic substrates such as rocks, tree bark, or soil that have low pH levels (4.5 - 5.5). The lichen can grow on both terrestrial and epiphytic substrates, but prefers damp and humid environments with high moisture content. It is sensitive to pollutants and thus cannot grow in areas with high levels of atmospheric contaminants.
Cultivation Methods for Melanelia subargentifera
For most lichens, including Melanelia subargentifera, cultivation is not necessary as they grow naturally in the wild. However, if you wish to cultivate this lichen for decorative purposes, it is essential to understand its basic requirements.
Firstly, select a location that replicates the natural habitat of the lichen. Usually, this would be a site that receives enough sunlight and a humid microclimate, such as a mossy rock surface or a tree trunk. In terms of temperature, Melanelia subargentifera prefers a cooler environment, and it may struggle in hot and dry conditions.
It is essential to use the right substrate to cultivate Melanelia subargentifera. The lichen prefers a mineral substrate such as rock or bark instead of organic media like soil. Therefore, consider collecting small fragments of the substrate directly from its natural environment and use that as a "seed" for your cultivation project.
Watering Needs for Melanelia subargentifera
Water is crucial for the survival of any plant, and lichens are no exception. However, watering techniques differ between lichens and conventional plants. Melanelia subargentifera, like most lichens, does not absorb water through its roots. Instead, it absorbs moisture from the surrounding atmosphere.
Therefore, it is vital to create a slightly moist environment around the lichen's growing area by spraying water occasionally. Avoid soaking the substrate, which can harm the delicate thallus. Instead, use a fine mist or a spray bottle to ensure an evenly moist environment.
Fertilization Needs for Melanelia subargentifera
Lichens rely on photosynthesis for their nutrient requirements, and they are capable of producing their food in the presence of sunlight. Therefore, fertilization is unnecessary for Melanelia subargentifera or any other lichen. However, supplementing the lichen's natural habitat with nutrients, such as dust or rainwater, can improve its growth and health.
Pruning Melanelia subargentifera
Pruning is not applicable to lichens like Melanelia subargentifera as they do not possess roots or leaves. Lichens grow slowly, and any physical disturbance can cause damage to the thallus.
However, you can remove unwanted debris or debris that falls on the surface where the lichen is growing. Also, it is essential to avoid disturbing the natural habitat surrounding the lichen as it can affect the balance of the ecosystem.
Propagation of Melanelia subargentifera
Melanelia subargentifera (Nyl.) Essl., commonly known as silver hair lichen, is a slow-growing crustose lichen.
Propagation methods
Propagation of this lichen is typically done through vegetative means, as it does not produce seeds or fruiting bodies. There are two primary methods for propagating this lichen: fragmentation and translocation.
Fragmentation
Fragmentation is the most common method of propagating Melanelia subargentifera. This involves physically separating a portion of the lichen from the parent colony and transplanting it to a new location. The fragment should be large enough to contain both the algal and fungal components of the lichen.
Once the fragment has been removed from the parent colony, it should be placed in a suitable location that mimics its natural habitat. This lichen species grows best in areas with high humidity, low light, and good air circulation.
Translocation
Translocation is the movement of an entire colony of lichen from one location to another. This is often done to preserve rare or threatened species or to introduce a species to a new habitat. Translocation is a more complex process than fragmentation.
The first step in translocation is to identify a suitable habitat for the lichen that mimics its natural environment. The new location must have similar light, humidity, and temperature conditions. Once a suitable location has been identified, the lichen colony is carefully removed and transported to its new home.
It is important to note that translocation should only be done by trained professionals and with the necessary permits and approvals.
Disease Management
Melanelia subargentifera is quite disease-resistant, but there are some ailments that can befall the plant.
Lichen spot
Lichen spot may occur if the plant is exposed to wet conditions for a long period of time. This disease can be managed by providing ample air circulation and avoiding overhead watering. Sanitation is also key in preventing the spread of the disease. Infected leaves should be removed and destroyed.
Leaf spot
Leaf spot is another common disease that can strike Melanelia subargentifera. This fungal disease appears as small, circular spots on the leaves. It is advisable to prune infected leaves, making sure not to spread the spores to the healthy parts of the plant. To control the growth of the fungus, a fungicide can be applied.
Root rot
Root rot can occur in Melanelia subargentifera if the soil is too wet. This disease can lead to stunted growth or even death of the plant. The best way to manage root rot is to improve the drainage of the soil. Allowing the soil to dry out between waterings is also advisable.
Pest Management
Melanelia subargentifera is susceptible to some pests, but these can be effectively controlled with appropriate pest management techniques.
Spider mites
Spider mites are tiny pests that can cause the leaves to turn yellow and drop off. To avoid the infestation of spider mites, the air humidity level should be maintained low. Natural predators like ladybugs and lacewings can be useful in keeping spider mite populations under control. In cases of severe infestation, an insecticidal soap can be used.
Aphids
Aphids are another pest that can cause harm to Melanelia subargentifera. These small, soft-bodied insects feed on the sap of the plant, causing it to wilt and appear stunted. To get rid of these pests, the plant can be sprayed with insecticidal soap or neem oil. In severe cases, a systemic insecticide can be applied.
Scale insects
Scale insects are small, waxy pests that can attach themselves to the stems and leaves of Melanelia subargentifera. These insects can be controlled through the use of insecticidal soap or neem oil. Following this, the scales can be manually removed.
