Overview of Albizia brachycalyx Oliv.
Albizia brachycalyx Oliv. is a tropical flowering plant that belongs to the family Fabaceae. This plant is native to the tropical and subtropical regions of Africa and Asia and is known by different common names depending on the region. Some of these names include Natal albizia, Kiraala, and Mukusu.
General appearance
Albizia brachycalyx is a small to medium-sized deciduous tree that can grow up to 20 meters tall. The tree has a straight trunk that is usually between 30-50 cm in diameter and a spreading crown that can reach up to 15 meters in diameter. Its bark is light gray, rough, and fissured, which often gives the appearance of scales or diamonds. The leaves are bipinnate, with 11-25 pairs of branches and a terminal one, which gives the leaf a feathery appearance. The flowers of the tree are spherical and highly perfumed, with white to pink petals, and are arranged in large clusters at the end of branches. The fruit of the tree is a flat, oblong pod that is brown and woody when mature, containing numerous seeds that are dispersed by the wind.
Uses
The tree's wood is hard and dense, making it ideal for construction. It is used for making furniture, poles, and various other household items. The leaves, bark, and seeds of the tree are also used in traditional medicine to treat various ailments. The leaves and bark are used as a remedy for fever, digestive disorders, and skin diseases, while the seeds are used to treat eye problems. Additionally, the flowers of the tree are used to make perfumes and its pods make good fodder for livestock.
In summary, Albizia brachycalyx is a highly valued plant due to its many uses, including its medicinal properties, and as a source of timber and fodder. Its attractive appearance also makes it a popular ornamental plant in some regions.
Light Requirements
The Albizia brachycalyx Oliv. plant requires full sunlight to partial shade for optimum growth. When the plant is young, it can tolerate partial shade. However, as it matures, it thrives best in full sunlight. A minimum of six hours of direct sunlight a day is required for the plant to thrive, and it can tolerate up to 10 hours of direct sunlight daily.
Temperature Requirements
The Albizia brachycalyx Oliv. plant thrives in warm temperatures. It can tolerate temperatures ranging from 20°C to 30°C (68°F to 86°F). The plant can grow in areas with a minimum temperature of 15°C (59°F) and a maximum temperature of 35°C (95°F). The plant cannot tolerate frost or extreme cold.
Soil Requirements
The Albizia brachycalyx Oliv. plant can grow in various types of soil, including loamy, sandy, and clay soils. However, it thrives best in well-draining soils rich in organic matter. Ideally, the pH of the soil should be between 6.0 and 7.5 for optimum growth. The soil should be fertile and moist but not waterlogged.
Cultivation
Albizia brachycalyx Oliv., commonly known as Flat-calyx Siris, is a deciduous tree. It requires well-draining, fertile soil with a pH ranging from 5.5 to 6.5. The plant thrives in full sun but can also survive in partial shade. It is recommended to grow the tree in areas with a minimum temperature of 12°C.
Watering Needs
The plant requires regular watering throughout the growing season. Watering should be done deeply and frequently to maintain the soil moist. The frequency of watering should be reduced during the winter season. Ensure that the soil is not waterlogged, as the plant is susceptible to root rot.
Fertilization
Albizia brachycalyx requires regular fertilization to thrive and maintain its growth rate. Fertilization should be done during the growing season, using a complete fertilizer with balanced nutrients. An additional phosphorous supplement can be added to promote root development and blooming.
Pruning
Pruning is essential in maintaining the shape of the tree and promoting blooming. Albizia brachycalyx should be pruned during its dormant period, late winter to early spring. Dead, diseased, or broken branches should be removed. Shape the tree by cutting back the branches to the desired length.
Propagation of Albizia Brachycalyx Oliv.
Albizia brachycalyx Oliv. can be propagated by both sexual and asexual means:
Sexual Propagation
Propagation of Albizia brachycalyx Oliv. through seeds is the most common method. This method is simple, and seeds can be easily collected by harvesting the mature pods. After harvesting the pods, they can be dried in the sun and then threshed to obtain the seeds. Once seeds have been obtained, they should be soaked in water for 24 hours to help speed up the germination process. After soaking, they can be sown in seed trays filled with a well-drained potting mix. The seed trays should be kept moist and in partial shade to promote germination. Once the seedlings have grown large enough, they can be transplanted into individual containers.
Asexual Propagation
Asexual propagation methods include layering, grafting, and cutting:
Layering
Layering involves bending low-hanging branches or stems towards the ground and covering them with soil. Roots will start to grow from the covered section, and once they are well established, the newly rooted plant can be cut from the parent plant and potted up. This method can take up to 12 months to produce a new plant.
Grafting
Grafting involves joining the stem of one plant, the scion, to the rootstock of another plant. This method is commonly used for Albizia brachycalyx Oliv. to provide them with a more robust root system and increase their resistance to disease. Grafting should be done during the growing season, and the grafted plant should be kept in partial shade and watered frequently during the first few weeks until new growth appears.
Cutting
Cutting propagation involves taking a stem cutting from a parent plant and rooting it in potting mix. Albizia brachycalyx Oliv. stem cuttings should be taken during the dry season when the plant is dormant. The cuttings should be treated with a rooting hormone to increase their chances of success. Once the cuttings have rooted, they can be transplanted to individual containers.
Disease management
Albizia brachycalyx Oliv. is prone to various diseases that can significantly affect its growth and development. Here are some common diseases that might affect the plant:
- Anthracnose: This fungal disease causes leaf spots, defoliation, and stunted growth. It is prevalent in warm and humid conditions. To manage anthracnose, remove and destroy infected plant material, avoid overhead irrigation, and provide proper plant spacing and ventilation.
- Leaf spot: Leaf spot is caused by different fungal pathogens that cause circular or irregular spots on leaves. The spots may be brown, gray, or black. Prune and destroy infected plant material, avoid overhead watering, and consider fungicides as a last resort.
- Powdery mildew: This fungal disease affects the leaves, stems, and flowers of Albizia brachycalyx. It causes white, powdery patches that can deform and stunt the plant's growth. Improve air circulation, avoid overhead watering, and remove infected plant material. You may also use fungicides to manage powdery mildew.
Pest management
Albizia brachycalyx Oliv. is also susceptible to pest attacks that can reduce its vigour and yield. Here are some common pests that might affect the plant and their corresponding management measures:
- Aphids: These sap-sucking insects can cause deformities, yellowing, and stunted growth. Use insecticidal soap or neem oil to control aphids. You can also introduce beneficial insects like ladybugs and lacewings that feed on aphids.
- Spider mites: Spider mites are tiny pests that suck the plant's sap, causing yellowing and defoliation. To manage spider mites, wash the plant with a strong spray of water to dislodge the pests. You can also introduce predatory mites that feed on spider mites.
- Caterpillars: Caterpillars can cause severe defoliation, weakening the plant and reducing its yield. Use Bacillus thuringiensis (Bt) pesticide to kill caterpillars. You can also handpick and destroy the caterpillars.
