Overview
Sideroxylon oxyacantha Baill. is a flowering plant that belongs to the family Sapotaceae. It is commonly known as Sideroxylon oxyacanthum, Oxycantha, and Wild Olive.
Origin and Distribution
It is native to Madagascar, and it can be found in other parts of Africa, such as Kenya and Tanzania. It has also been introduced to other regions of the world, including India and Sri Lanka.
General Appearance
Sideroxylon oxyacantha Baill. is a small to medium-sized tree that can grow up to 20 meters in height. It has a dense and rounded crown with dark green leaves that are elliptic to obovate in shape. The tree produces small, white, and fragrant flowers that bloom during the winter months. The fruit of the tree is a small drupe that is about 2 centimeters in diameter. The fruit is green when young and turns black when ripe, and it contains a single seed.
Uses
The wood of Sideroxylon oxyacantha Baill. is hard, dense, and durable, making it suitable for construction, furniture, and other woodworking projects. The tree is also used in traditional medicine to treat various ailments such as coughs, fever, and malaria. The fruit of the tree is edible, and some local communities use it to make jams and jellies. Additionally, the tree is used for landscaping and as an ornamental plant for its attractive foliage and white flowers.
Light Requirements
Sideroxylon oxyacantha Baill. requires a lot of sunlight to grow healthily. This plant thrives in full sunlight, and it is essential to ensure that it receives at least six hours of direct sunlight every day. Insufficient sunlight can result in stunted growth and poor flower development.
Temperature Requirements
Sideroxylon oxyacantha Baill. grows in subtropical and tropical regions. As such, it needs warm temperatures to thrive. The optimal temperature range for this plant is between 20-30°C. Extreme temperatures can cause damage to the plant, and temperatures below 10°C can cause the plant to become dormant.
Soil Requirements
Sideroxylon oxyacantha Baill. prefers well-draining soils that are rich in nutrients. The soil should be slightly acidic, with a pH range of 5.5 to 6.5. Sandy loam soil is ideal for this plant because it provides good drainage while retaining some moisture. It is essential to ensure that the soil is not too compact as it can hinder root development and reduce the plant's ability to absorb nutrients and water.
Cultivation
Sideroxylon oxyacantha Baill. is a shrub that prefers a moist, well-drained soil. It can be grown in full or partial sunlight, but it may require some shade during the hottest part of the day in areas with harsh sun.
This plant can be propagated through cuttings or seeds. Seeds should be soaked and sown in a seed tray, while cuttings should be taken from new growth and rooted in a propagator. Mature plants can be transplanted into larger containers or directly into the ground.
Watering Needs
Sideroxylon oxyacantha Baill. requires regular watering to thrive. It prefers a consistently moist soil, so it is important to water deeply and frequently during dry periods. However, care should be taken not to overwater, as this can lead to root rot.
Fertilization
To encourage healthy growth and flowering, Sideroxylon oxyacantha Baill. should be fertilized with a balanced, slow-release fertilizer every two to three months during the growing season.
The fertilizer should be applied according to the manufacturer's instructions, and care should be taken not to over-fertilize, as this can lead to excessive growth at the expense of flowering.
Pruning
Sideroxylon oxyacantha Baill. benefits from regular pruning, which promotes a denser, bushier growth habit and can help to maintain its size and shape. Pruning should be carried out in the spring, before new growth appears.
Dead or damaged branches should be removed, as well as any crossing or rubbing branches. The tips of new shoots can also be trimmed to promote branching and encourage a bushier growth habit.
Propagation of Sideroxylon oxyacantha Baill.
Sideroxylon oxyacantha Baill., commonly called "bois d'ècaille" or "greenheart," can be propagated vegetatively and through seeds. Propagation through seeds is preferred since it is cheaper and easier to handle. However, seeds may exhibit poor germination rates and have high dormancy levels.
Propagation through Seeds
Seeds must be collected when they are fully mature and have turned brown. The best time to collect seeds is during the dry season when the fruit capsules have split open, revealing the brown seeds inside. The collected seeds should be washed thoroughly, and any damaged or infected seeds should be discarded. Prior to planting, seeds can be stored in dry sand or vermiculite at room temperature for up to six months.
Seeds can be germinated using different methods, including direct sowing or nursery raising. In direct sowing, seeds are sown directly into the planting site, while in nursery raising, seeds are sown in seedbeds and the resulting seedlings are transplanted to the planting site.
In seedbeds, seeds are sown at a depth of 1.5 to 2.0 cm and covered with sand or fine soil. Watering should be done gently to avoid splashing the seeds away. Germination may take 20 to 50 days. Once the seedlings have emerged, they can be thinned and transplanted to individual containers or bags.
Vegetative Propagation
Vegetative propagation of Sideroxylon oxyacantha can be done through stem cuttings, air layering, or grafting. Stem cuttings are commonly used for propagation since they can produce identical plants to the parent plant.
Stem cuttings should be collected from healthy and disease-free plants during the dormant season. Cuttings should be approximately 10 to 15 cm long, with four to six nodes. The leaves on the lower nodes should be removed, and the cutting should be dipped in rooting hormone powder to enhance root formation. The cuttings are then planted in a rooting medium and placed in a shaded area with high humidity. Rooting may take up to 2 to 3 months.
Air layering involves wounding the stem of the parent plant and applying a rooting hormone to the wounded portion. The wounded area is then covered with moist sphagnum moss and wrapped with plastic film to create a humid environment. Once roots have formed, the stem is cut and planted in a rooting medium.
Grafting is not commonly used for propagation of Sideroxylon oxyacantha since it is difficult to graft. However, it can be done through cleft or side grafting using young seedlings as rootstock and scions collected from mature healthy trees.
Disease and Pest Management of Sideroxylon Oxyacantha Baill.
Sideroxylon oxyacantha Baill., commonly known as African boxwood or milkwood, is a small, evergreen tree native to central and southern Africa. In its natural habitat, it is susceptible to various diseases and pests that can adversely affect its growth and development.
Common Diseases
The most common diseases that affect S. oxyacantha are fungal in nature. The following are a few examples:
Leaf Spot
Leaf spot is a fungal disease that causes small, circular spots on the leaves that may turn brown or black. This disease can cause defoliation of the plant. To manage leaf spot, remove infected leaves promptly and apply a fungicide as recommended by a professional.
Powdery Mildew
Powdery mildew is a fungal disease that appears as a white, powdery coating on leaves and stems. The leaves may become distorted and develop chlorotic spots. To manage powdery mildew, apply a fungicide as recommended by a professional and maintain proper air circulation around the plant.
Common Pests
S. oxyacantha is also susceptible to various pests that can cause significant damage to the plant. The following are a few examples:
Scale Insects
Scale insects are sap-sucking pests that attach themselves to the leaves, stems, and branches of the plant. They secrete a sticky substance called honeydew that can attract other pests like ants. To manage scale insects, prune and dispose of infested plant parts and apply an insecticide as recommended by a professional.
Caterpillars
Caterpillars are the larvae of moths and butterflies that feed on the leaves of the plant. They can cause significant defoliation if left unchecked. To manage caterpillars, handpick and remove them from the plant or apply an insecticide as recommended by a professional.
In conclusion, S. oxyacantha is a beautiful plant that can be adversely affected by various diseases and pests. It is vital to monitor the plant regularly and promptly take action if any issues are identified. A professional can recommend the best methods to manage diseases and pests for the specific plant species.
