Overview of Albizia evansii Burtt Davy
Albizia evansii Burtt Davy, also known as the flat-crown albizia, is a flowering plant that belongs to the family Fabaceae. The plant is native to East Africa, particularly in Kenya and Tanzania. It is a common tree in tropical and subtropical regions and is known for its ornamental and medicinal properties.
Appearance of Albizia evansii Burtt Davy
The tree grows up to a height of 20 meters with a rounded or flat-topped crown. It has smooth, grayish bark and a straight bole that may or may not have buttresses. The leaves are up to 40 centimeters long, dark green and composed of small leaflets. Albizia evansii produces fragrant, soft, pinkish flowers, which are about 2.5 centimeters in diameter. The flowers are borne in spherical clusters and attract bees, butterflies and other pollinators. The fruit of the tree is a flat, oblong pod that is around 20 centimeters long and eight centimeters wide.
Uses of Albizia evansii Burtt Davy
The tree has many uses, particularly in traditional medicine. The bark and roots of the tree are used to treat various ailments, including skin conditions, fever, and malaria. The tree is also used as a source of timber, which is used in the construction of furniture and buildings due to its durability and strength. Additionally, the plant is grown for its ornamental value and provides shade in home gardens and parks.
Common Names of Albizia evansii Burtt Davy
Albizia evansii is known by various common names, including the flat-crown albizia, East African albizia, and Mkangazi in Swahili.
Growth Conditions of Albizia evansii Burtt Davy
Albizia evansii is a deciduous tree that is commonly found growing in semi-arid regions of East Africa. This drought-tolerant plant requires specific growth conditions to flourish successfully. Below are some of the key conditions that are essential for its growth:
Light
Albizia evansii requires full sunlight to grow well. It cannot tolerate shady conditions and requires at least 6 hours of direct sunlight per day. Areas with partial or full shade will lead to slow growth or even death of the plant. Therefore, it should be planted in areas where there is maximum exposure to sunlight, preferably in open fields or near the edges of forests.
Temperature
The plant grows well in high temperatures of between 20 to 35 degrees Celsius. It can, however, survive in temperatures as low as 5 degrees Celsius. The plant is sensitive to frost and cannot withstand freezing temperatures. Therefore, it should be grown in areas with warm to moderate temperatures.
Soil Requirements
The plant requires well-drained soils with a pH range of 5.0 to 8.0. It can grow well in different types of soils, including sandy, loamy, and clay soils. However, Albizia evansii grows best in deep, fertile, and well-aerated soils. Its roots are shallow, and it requires frequent watering to keep the soil moist but not waterlogged.
Other critical growth conditions for Albizia evansii include fertilization, pruning, and pest management. Proper fertilization with nitrogen, phosphorus, and potassium can enhance its growth and development. Pruning should be done regularly to enhance the tree's shape and remove any damaged or diseased branches. Pest management is also crucial since the plant is prone to attack by various insects such as thrips and mealybugs, which can cause significant damage.
By providing these essential growth conditions, Albizia evansii can grow to its full potential, providing benefits such as shade, windbreaks, and timber.
Cultivation Methods
Albizia evansii Burtt Davy is a tropical tree species that thrives well in areas with high humidity (above 60%) and warm temperatures (25°C to 30°C). The tree should be grown in a well-draining soil medium with a pH ranging from 5.5 to 7.0.
The seeds of Albizia Evansii Burtt Davy can be obtained from a seed bank. After germination, the seedlings should be transplanted into pots and kept in the shade for several days before being gradually introduced to direct sunlight.
Watering Needs
The tree requires adequate soil moisture to grow and develop correctly. However, excessive watering can lead to water-logging, which can negatively affect the growth and development of the roots. Therefore, the tree should be irrigated as needed and only when the soil is dry.
The frequency of watering should be increased during the dry season, and the tree should be watered in the morning or late afternoon. Overhead irrigation should be avoided to prevent the spread of foliar diseases.
Fertilization
Albizia evansii Burtt Davy's growth can greatly benefit from fertilization with a balanced mixture of nitrogen, phosphorus, and potassium. The fertilizer should be applied to the tree's root zone every 2-3 months during the growing season.
The amount of fertilizer to be applied to the tree will depend on the tree's age, size, and growth rate. A soil test can be conducted to determine the soil's nutrient levels and what kind of fertilizer the plant needs.
Pruning
Pruning should be done in early spring before new growth emerges. The tree should be pruned to remove dead or damaged branches, branches that cross, and diseased portions. Pruning can help improve the tree's form, manage its size, and promote blooming.
When pruning the tree, it's essential to use sterilized pruning shears and make clean cuts above the branch collar to promote rapid healing. In addition, it's recommended that no more than one-third of the tree's crown be removed in a single season.
Propagation of Albizia evansii Burtt Davy
Albizia evansii Burtt Davy, commonly known as the Forest Acacia, is a medium-sized tree that can grow up to 20 m tall. It is native to East Africa and is known for its beautiful, feathery foliage and eye-catching flowers. Propagation of Albizia evansii Burtt Davy is relatively easy and can be done through various methods.
Seed Propagation
The most common method of propagation for Albizia evansii Burtt Davy is through seeds. The seeds from mature pods are collected, cleaned, and soaked in water for 24 hours before sowing. Sowing can be done in a seed bed or a container filled with a well-draining, fertile, and moisture-retentive soil mix. The seeds should be covered with a thin layer of soil and kept moist through regular watering. Germination occurs within 3-6 weeks, and the seedlings are transplanted to individual containers or directly into the field after 3-4 months.
Cutting Propagation
Albizia evansii Burtt Davy can also be propagated through stem cuttings. Softwood or hardwood cuttings may be used, and rooting hormone may be applied to improve the success rate. Cuttings should be taken from healthy, disease-free plants, and the cut ends should be treated with a fungicide. The cuttings can be rooted in containers filled with a well-draining, sterile rooting medium. They should be kept under high humidity and moderate light conditions until rooting occurs, which usually takes about 2-3 weeks. Once rooted, the cuttings can be transplanted to individual containers or directly into the field after 2-3 months.
Air-Layering Propagation
Air-layering is another propagation method that can be used for Albizia evansii Burtt Davy. This method involves wounding a small section of a branch to encourage the formation of roots at the point of injury. The wounded area is then covered with a moist, sterile medium, such as sphagnum moss, and secured with a plastic wrap. The branch is left undisturbed for a few months until roots have developed. The rooted section of the branch can then be cut off and transplanted to a container or directly into the field.
Grafting Propagation
Grafting is not a common method of propagation for Albizia evansii Burtt Davy, but it can be used to maintain desirable traits or to propagate a new variety of the plant. The scion, which is the desired variety, is grafted onto a rootstock of a closely related species. The graft union should be wrapped with a grafting tape or an elastic band to hold the two parts together until they have fused. Grafted plants should be kept under high humidity and moderate light conditions until the graft has fully healed, which usually takes about 2-3 weeks. The grafted plants can then be transplanted to individual containers or directly into the field after 3-4 months.
Disease and Pest Management of Albizia evansii Burtt Davy
Albizia evansii Burtt Davy is a relatively disease-resistant plant, but it's not entirely immune to diseases and pests. Here are some of the most common issues that can affect the plant and suggested ways to manage them:
Diseases
Leaf spot disease: Leaf Spot disease is caused by a fungus and is prevalent in wet conditions. This disease manifests itself as small spots on the leaves, which expand and join, causing a considerable loss of foliage. To manage the disease, remove and destroy all infected leaves, and employ adequate canopy management to improve airflow, which will reduce moisture and decrease the chances of the disease spreading.
Root rot: Root rot is a fungal disease that attacks the roots of Albizia evansii and causes them to rot and die. This disease spreads quickly since it thrives in high humidity. Proper drainage and well-draining soil are vital in preventing root rot. To manage the disease, removing and destroying infected plants and planting in sanitized soil may be necessary.
Pests
Pod borers: The pod borer is a common Albizia evansii pest that feeds on the plant's flowers and seeds. To manage this pest, remove and destroy affected flowers, increasing the frequency of scouting and handpicking of the caterpillars can prove helpful in controlling the pest.
Mealybugs: Mealybugs attack plant sap, which weakens the plant, causing it to lose its vitality. These pests will cover themselves with a waxy substance to protect themselves, making it hard to see or control them effectively. To manage mealybugs, regular scouting, and the use of insecticidal soap or neem oil can help keep the infestation under control.
Preventing disease and pest infestation is more effective than managing them, and proper maintenance of Albizia evansii is key to achieving this. Proper watering practices, maintaining well-drained soils, regular pruning to remove dead or diseased plant parts, sanitation after pruning, and proper nutrient management can all help to keep the plant healthy.
