Description
Collema tenax (Sw.) Ach. var. substellatum (H. Magn.) Degel. is a type of lichen species belonging to the family Collemataceae. It is also commonly known as ‘rock greenshield’ or ‘tortoise lichen’ due to its physical appearance. This lichen is highly adaptable and can grow in a variety of habitats including rocky areas, tree trunks, and soil-rich environments.
Appearance
Collema tenax var. substellatum has a distinct and unique appearance, which makes it easy to identify. It has a greenish-grey to an olive-green color that forms a thin layer over the surface of rocks or soil. The lichen has a leathery texture and a crust-like form. It has a prominent raised edge and a flat center giving it a shield or tortoise-like appearance. The underside of this lichen has a black color with a white margin.
Origin
Collema tenax var. substellatum is widely distributed in North America, Europe, and the Asian continent. It grows in various habitats and climatic conditions due to its adaptability. This lichen prefers moist environments, especially during the rainy and humid seasons. It is commonly found in forested areas, rocky outcrops, and along the banks of streams and rivers.
Uses
Collema tenax var. substellatum has both medicinal and ecological uses. The lichen produces various chemical compounds that possess antimicrobial and anti-inflammatory properties. It has been used in traditional medicine to create topical treatments for skin infections and ulcers. Additionally, it has shown antimicrobial activity against various common pathogens such as staphylococcus aureus and salmonella typhimurium. Ecologically, rock greenshield is an indicator of healthy soil and a sign of clean air.
Light requirements
Collema tenax var. substellatum is a chlorophyllous lichen that grows best in partial to full shade. It can tolerate some direct sunlight, but too much sun exposure can harm the plant. In direct sunlight, it may have a pale or bleached appearance.
Temperature requirements
This lichen grows best in cool and moist environments such as forests, rocky areas, and stream banks. It can tolerate a wide range of temperatures, including freezing temperatures. However, in extremely hot and dry conditions, the plant may become dormant or die.
Soil requirements
Collema tenax var. substellatum is a soil-dwelling plant that prefers moist, well-drained, and nutrient-rich soils. It can grow on a variety of substrates, including rocks, moss, and tree bark. The plant is known to prefer acidic soils and is often found in areas with a pH between 4.5 and 6.5.
Cultivation of Collema tenax (Sw.) Ach. var. substellatum (H. Magn.) Degel.
Collema tenax (Sw.) Ach. var. substellatum (H. Magn.) Degel. is a lichen plant that can grow both indoors and outdoors. To cultivate this plant effectively, start by choosing an appropriate location, soil, and pot or container.
For indoor growth, choose a brightly-lit area that receives partial or indirect sunlight. For outdoor growth, select a shaded location to avoid excessive sunlight exposure. Collema tenax prefers well-drained soil that is slightly acidic with a pH between 5.5 to 7.0. Pot or container size should reflect the size of the plant, ensuring that it has enough space to grow.
Watering Needs of Collema tenax (Sw.) Ach. var. substellatum (H. Magn.) Degel.
Collema tenax requires adequate moisture to grow and thrive. Watering needs may vary, depending on the location and growing conditions. However, the general rule of thumb is to keep the soil moist but not waterlogged.
Indoor plants may require watering every 7 to 10 days, depending on the humidity in the area. Outdoor plants may require more frequent watering, especially during hot and dry seasons. Always check the soil moisture before watering to avoid overwatering or underwatering the plant.
Fertilization of Collema tenax (Sw.) Ach. var. substellatum (H. Magn.) Degel.
Fertilization can help Collema tenax plants grow faster and healthier. However, lichens are unique organisms that do not have roots or leaves, so fertilization must be done cautiously. Using a light mixture of organic fertilizer or liquid seaweed fertilizer can provide the necessary nutrients without harming the plant.
Apply fertilizer once a month during the plant's growing season, which occurs in the spring or early fall. Avoid fertilizing during hot or dry periods, as it may cause plant damage.
Pruning Collema tenax (Sw.) Ach. var. substellatum (H. Magn.) Degel.
Pruning is not typically required for Collema tenax plants since they do not have leaves or branches. However, removing any dead or damaged parts of the plant can help improve its overall health and appearance.
Use a sharp and clean pair of scissors or pruning shears to cut away any dead or damaged parts of the plant. Always sanitize your tools before and after pruning to prevent the spread of any disease or infection.
Propagation of Collema tenax var. substellatum
Collema tenax var. substellatum can be propagated through two main methods:
Fragmentation
Fragmentation is the simplest propagation method for Collema tenax var. substellatum. It involves physically dividing the lichen into smaller fragments and planting them in suitable substrate. It is important to ensure that each fragment contains both the fungal and algal components of the lichen for successful propagation.
The best time for fragmentation is during the early spring or fall. This is because the lichen is more active during these seasons and is able to regenerate more efficiently. The fragments should be planted in moist soil or on suitable rocks in shaded areas. Regular misting can help to maintain the required moisture levels for successful growth.
Soredia Propagation
Soredia propagation is an alternative method used for propagation of Collema tenax var. substellatum. Soredia can be found on the surface of the lichen and are small, dust-like particles that contain both fungal and algal components. They can be quite easily dispersed by wind and can be propagated by simply scattering them over suitable substrate. However, the success rate of soredia propagation is generally lower compared to fragmentation and it may take longer for the lichen to establish itself.
When propagating Collema tenax var. substellatum through soredia, it is important to provide a suitable substrate that can support the growth of the lichen. Rocks, gravel or soil with high organic matter content are suitable as substrates for lichen growth. The soredia should be sprinkled lightly over the substrate and pressed lightly into the surface. It is important to maintain the substrate moist and to avoid exposing the growing lichen to direct sunlight.
Disease Management
Collema tenax var. substellatum is generally tolerant of diseases, but certain environmental conditions can make it susceptible to various infections. The most common diseases that might affect this plant are:
- Fungal leaf spots: These appear as circular or irregularly shaped brown spots on the leaves. To manage this disease, it is important to keep the leaves dry and limit overhead irrigation. You can also use fungicides to control severe infections.
- Cankers: These are areas of dead tissue on the stems of the plant. They can be caused by various fungi or bacteria. To manage this disease, it is important to remove infected branches or stems as soon as you notice them. You can also use fungicides or bactericides if the infection is severe.
- Powdery mildew: This disease causes a white, powdery coating on the leaves, stems, and flowers. It is prevalent in high humidity and low light conditions. To manage this disease, you can prune infected parts of the plant and use fungicides to control the spread of the disease.
Pest Management
Collema tenax var. substellatum is also susceptible to pests that can cause damage to the plant. The most common pests that might affect this plant are:
- Spider mites: These pests are tiny, spider-like creatures that live on the underside of leaves. They can cause yellowing, dryness, and necrosis of the leaves. To manage spider mites, you can use insecticidal soap or neem oil to control their population.
- Aphids: These are small, soft-bodied insects that feed on the plant's sap. They can cause stunted growth, yellowing, and wilting of the leaves. To manage aphids, you can use insecticidal soap or neem oil to control their population.
- Mealybugs: These pests are tiny, white, cotton-like insects that feed on the plant's sap. They can cause stunted growth, yellowing, and wilting of the leaves. To manage mealybugs, you can use insecticidal soap or neem oil to control their population. You can also use cotton swabs dipped in alcohol to remove them from the plant.
It is important to regularly inspect your Collema tenax var. substellatum plant for signs of disease and pests. Early detection and management can prevent severe damage to the plant and ensure its healthy growth.
