Origin
Caloplaca oblongula (H. Magn.) Wetmore is a species of lichen that belongs to the family Teloschistaceae. It is commonly found growing on rocks, predominantly in the Northern Hemisphere, including North America, Europe, and Asia.
Common Names
Caloplaca oblongula is commonly known as the blue stone lichen, thanks to the blue-gray hue it presents when growing on rocks. Other common names for this plant also include the oblong-fruited gold lichen and the narrow-fruit gold lichen.
Uses
Caloplaca oblongula does not have any significant commercial or medicinal uses. However, it is an essential plant species in environmental monitoring and serves as a bioindicator for air pollution in urban areas. Additionally, the blue stone lichen plays a vital role in the ecological balance of its habitat, supporting other important plant and animal species.
General Appearance
Caloplaca oblongula has a distinctive appearance, characterized by small, round, flattened, or convex lobes, which are usually about 2-7mm in diameter. The lobes are usually clustered together in groups. The plant's thallus is yellow, and the apothecia, which are the fruiting structures, are distinctively blue-gray in color.
The stems of the Caloplaca oblongula are usually absent, and the lobes perforate the substrate. This distinctive feature makes it a crustose lichen. The lichen's photobiont, which is responsible for photosynthesis, is a green alga and/or cyanobacterium.
Light Requirements
Caloplaca oblongula is a photosynthetic lichen that requires a moderate amount of light for growth and development. It can tolerate both direct and indirect sunlight, but it prefers light shade or partial sunlight. Exposure to intense direct sunlight for prolonged periods can cause damage to its photosynthetic apparatus.
Temperature Requirements
The optimal temperature range for the growth of Caloplaca oblongula is between 10°C and 20°C. It can survive in temperatures as low as 5°C or as high as 30°C, but prolonged exposure to extreme temperatures can have adverse effects on its growth and development. The lichen can withstand occasional frost, but extended periods of sub-zero temperatures can be lethal to it.
Soil Requirements
Caloplaca oblongula is a lichen that can grow on a variety of substrates, including soil, rocks, and tree bark. It prefers well-drained soil with good air circulation and a pH range of 6 to 8. High levels of organic matter in the soil can impede its growth as they can encourage the growth of other organisms that may outcompete it for resources. The lichen can also grow on arid or semi-arid soils, but it requires occasional moisture for survival.
Cultivation
Caloplaca oblongula is best cultivated in well-draining soil. It can be grown in pots or directly on the ground. The plant prefers a bright and partially shaded environment, and it is best grown in areas with average humidity.
Watering needs
Caloplaca oblongula requires moderate watering. The plant should be watered when the top inch of soil is dry to the touch. Overwatering should be avoided, as it can lead to root rot and ultimately death of the plant.
Fertilization
Fertilization of Caloplaca oblongula is not necessary. However, during its growth stage, adding low-nitrogen fertilizer to the soil can help promote optimal growth. Care should be taken to avoid over-fertilization, which can harm the plant.
Pruning
Pruning of Caloplaca oblongula is minimal, as the plant does not require excessive pruning. However, to maintain a neat appearance and encourage bushier growth, it is recommended to trim any dead or diseased stems or leaves. The plant can also be pinched back to promote fuller growth.
Propagation of Caloplaca Oblongula
Caloplaca oblongula, also known as H. Magn. Wetmore, is a crustose lichen species found on rocks and soil. Propagation of Caloplaca oblongula can be done through vegetative or asexual methods. The following are the propagation methods used for Caloplaca oblongula.
Vegative Propagation
Vegative propagation involves the use of thallus fragments to produce new individuals. Thallus fragments can be used to produce new colonies of Caloplaca oblongula. The fragments are collected from healthy plants and are transferred to a suitable substrate. The substrate is moistened regularly to facilitate the growth of new individuals.
Asexual Propagation
Asexual propagation involves the production of new individuals from specialized structures such as soredia and isidia. Soredia are powdery structures produced by the breaking up of vegetative tissue. Isidia are branch-like structures that grow out of the thallus. Both soredia and isidia are dispersed by wind or rain and can grow into new individuals under favorable conditions.
Propagation of Caloplaca oblongula can be done in the laboratory or in the field. However, propagation in the field is dependent on favorable environmental conditions such as temperature, moisture, and light. In addition, the substrate should provide suitable nutrients and support the growth of the plant.
Disease Management
Caloplaca oblongula is a species of lichen that is typically resistant to most types of diseases. However, they can become vulnerable to fungal infections in some cases. Fungi like phytophthora and pythium tend to attack the plant tissue and cause root rot, which can lead to the plant's death.
To prevent root rot, it is recommended to avoid overwatering the plant and ensure proper drainage. If there is a chance of infection, the plant should be treated with a fungicide as soon as possible. Chemical fungicides like copper-based products are often effective in controlling fungal disease in Caloplaca oblongula.
Pest Management
Caloplaca oblongula is generally not affected by pests. However, some insects like aphids, mites, and scale insects may sometimes attack the plant. These pests typically feed on the lichen, causing discoloration and tissue damage that weakens the plant.
If these insects are detected on the plant, it is recommended to remove them manually using a soft brush or a jet of water. It is also possible to apply insecticides like neem oil or insecticidal soap to eliminate the pests' presence. These solutions are mechanical barriers that interfere with the pests' ability to feed and grow, effectively reducing their populations.
