Overview of Evernia divaricata (L.) Ach.
Evernia divaricata (L.) Ach. is a species of lichen in the family Parmeliaceae. It is commonly known as "tree moss" or "oakmoss," and is known for its distinctive fragrance.
Origin and Distribution
Evernia divaricata (L.) Ach. is widely distributed in temperate regions throughout the world. It is particularly common in Europe, but can also be found in North America and Asia.
General Appearance
Evernia divaricata (L.) Ach. is a foliose lichen that grows on the bark of trees, particularly oak and other deciduous species. It typically forms large, bushy clusters of pale green or greyish-green fronds that are flattened and strap-shaped. The thallus, or body of the lichen, is composed of branched, ribbon-like lobes that overlap or interweave, forming a dense mat on the surface of the tree bark. The underside of the fronds is typically dark brown or black, with numerous small, root-like structures called rhizines that attach the lichen to the bark.
Uses of Evernia divaricata (L.) Ach.
Evernia divaricata (L.) Ach. has been used in perfumery for centuries due to its unique fragrance that is often described as woody, earthy, and musky. It is commonly used as a base note in perfumes, adding depth and complexity to the scent. Oakmoss absolute, a concentrated extract of Evernia divaricata (L.) Ach. is also used in aromatherapy as a natural remedy for respiratory issues and inflammation. Historically, it has also been used in traditional medicine for its antiseptic and anti-inflammatory properties.
Light Requirements
Evernia divaricata is adapted to grow in areas with moderate to high levels of light intensity. This species can grow in both full sun and partial shade conditions. However, excessive exposure to sunlight can cause photo-oxidative damage, which may affect the growth and survival of the plant.
Temperature Requirements
Evernia divaricata is well adapted to grow in a broad range of temperature conditions. The optimum temperature range for this plant is between 15°C and 25°C. However, the growth rate and physiological activity of the plant may decline outside this temperature range.
Soil Requirements
Evernia divaricata can grow on different types of soil, including acidic, neutral, and alkaline soils. The plant prefers a well-drained soil that is rich in organic matter. Excessively wet or waterlogged soils may reduce the growth rate of the plant and cause root damage, which may ultimately lead to plant death.
Cultivation methods
Evernia divaricata (L.) Ach. is a type of lichen that grows on the bark of trees. Cultivating it can be challenging, but it can be grown both indoors and outdoors. When cultivating Evernia divaricata indoors, it should be placed near a window to ensure it receives adequate lighting.
If cultivating the plant outdoors, it is recommended to grow it on the bark of trees, as this will provide the plant with the necessary nutrients for growth. It is important to note that Evernia divaricata requires clean air to grow, and exposure to pollutants can have detrimental effects on its development.
Watering needs
Evernia divaricata does not require frequent watering. In fact, overwatering can kill the plant. The plant should be watered only when the substrate is almost completely dry. If growing the plant indoors, it can be misted with water occasionally to provide it with adequate moisture.
Fertilization
Unlike other plants, Evernia divaricata does not require fertilization. The plant can derive all its nutrients from the surrounding environment and does not need additional fertilization to thrive. Over-fertilizing can even harm the plant, so it is best not to fertilize this plant at all.
Pruning
Pruning is not necessary for Evernia divaricata. The plant grows slowly and will not require pruning to control its size or shape. However, if some parts of the plant become dead or damaged, they can be removed with sharp scissors or tweezers to ensure the health of the plant.
Propagation of Evernia divaricata (L.) Ach.
Evernia divaricata (L.) Ach. is a lichen species that grows on trees and rocks in temperate to subalpine forests. It is commonly found in North America and Europe. This plant can be propagated through vegetative methods such as fragmentation, as well as through sexual reproduction.
Fragmentation
Fragmentation is a simple method of propagating Evernia divaricata. In this process, small pieces of thallus are removed from the parent plant and attached to a suitable substrate. The substrate can be a tree branch or a rock, and it should have similar characteristics to the original site where the parent plant was growing. The fragment should be placed in a shaded location and misted regularly until it establishes itself on the substrate. This method of propagation is commonly used in the plant's natural habitat.
Sexual Reproduction
Evernia divaricata reproduces sexually by producing spores that are dispersed by wind. This process is more complicated than vegetative reproduction, but can result in greater genetic diversity. To grow Evernia divaricata from spores, a sterile substrate such as petri dishes and agar should be used. The spores should be collected from mature thalli and then placed on the substrate. The substrate should be kept moist and in a shaded location, and the spores should germinate after a few weeks. The young thalli can then be transplanted to a suitable substrate.
Disease Management of Evernia Divaricata
Evernia divaricata is a lichen that is generally hardy and disease-resistant. However, the presence of some common diseases can be detrimental to the survival of the plant. These diseases could lead to the decline of the plant life, and hence it is essential to take early preventive measures.
Yellowing and Browning of the Thallus
Yellowing and browning of the thallus are the two most common symptoms of Evernia divaricata affected by fungal infections. It is mostly caused by overwatering, which creates a moist environment for the growth of fungus. To control this infection, the plant must be pruned, and the affected areas must be properly disposed of to prevent further spread of the fungus. Besides, a proper watering schedule to avoid waterlogging and maintaining proper air circulation are necessary precautions to prevent such infections. Fungicides could be applied if it is severe.
Lichen Mite Infestation
Lichen mites are tiny pests that generally attack the thallus of Evernia divaricata. The infestation is characterized by small, brown, and round patches on the surface of the thallus. As soon as the infestation is detected, it is necessary to prune and remove the affected areas. To prevent such infestations, it is advisable to maintain a healthy environment for the plant by properly watering and maintaining proper air circulation around the plant. Chemical controls could be used if the infestation is not controlled naturally by these measures.
Pest Management of Evernia Divaricata
In addition to diseases, several pests can harm the growth and survival of Evernia divaricata. Identification, early detection, and quick control measures are essential to control these pests' spread.
Scale Insects Infestation
Scale infestations are common in Evernia divaricata, and they are characterized by round, crusty brown patches attached to the thallus's surface. These pests suck sap from the plant's tissues, resulting in a weakened and sickly plant. To prevent infestations, the plant must be regularly pruned, and the affected areas must be discarded. Insecticides could be used if the infestation is severe.
Caterpillar Infestation
Caterpillars are species-specific, and some species are known to attack Evernia divaricata. The infestation is characterized by foliage damage, including small holes and entire sections of the thallus being consumed. To prevent such infestations, the plant surrounding must be regularly pruned, and insecticides should be used if required.
