Origin
Ptycholobium biflorum (E.Mey.) Brummitt subsp. angolensis (Baker) Brummitt, commonly known as Angolan ivory tree, is a flowering plant species that belongs to the family Fabaceae and is native to Angola, a country located in southwestern Africa.
Common Names
The plant is commonly known as Angolan ivory tree, Angola ivory, Angola ivory wood, and Muiri in some parts of Angola.
Appearance
Ptycholobium biflorum subsp. angolensis is a deciduous tree that can grow up to 20 m tall. The trunk is straight with a diameter of up to 100 cm. The bark is light brown and rough. The leaves are pinnate, 20–30 cm long, with 6–9 leaflets. The leaflets are elliptical, 6–15 cm long, and 3–5 cm wide. The flowers are borne on axillary racemes and are white or cream-colored. The fruit is a flat, oblong pod, about 15 cm long, with a woody texture and containing many seeds.
Uses
Ptycholobium biflorum subsp. angolensis has several uses, particularly in Angola. The wood is heavy, hard, and durable, making it suitable for furniture, cabinetry, flooring, and other construction materials. Additionally, the bark is used in traditional medicine to treat various ailments such as pain, inflammation, and fever. The seeds contain high levels of oil and are used in soap making and as a lubricant. Finally, the tree is cultivated as an ornamental plant in some areas due to its attractive white or cream-colored flowers.
Growth Conditions of Ptycholobium biflorum subsp. angolensis
Light Requirements: Ptycholobium biflorum subsp. angolensis grows best in full sun to partial shade. It tolerates some shade but may not flower as prolifically in shaded conditions.
Temperature Requirements: This plant is adapted to hot, dry conditions and can tolerate a wide range of temperatures. It is hardy to USDA zones 9-11 and can handle temperatures as low as 25°F (-4°C) when established.
Soil Requirements: Ptycholobium biflorum subsp. angolensis prefers well-drained soils and can grow in a range of soil types. It is not particular about soil pH, but it does require good drainage to avoid root rot. It is best to avoid heavy, clay soils.
Water Requirements: This plant is drought-tolerant once established and requires little water. Watering should be done sparingly, especially in humid climates where excessive moisture can lead to fungal disease. Watering should be reduced in the winter months to prevent root rot.
Fertilizer Requirements: Ptycholobium biflorum subsp. angolensis does not require fertilization but can benefit from occasional light applications of a balanced fertilizer. Avoid over-fertilization, as this can lead to excessive vegetative growth at the expense of flowering.
Propagation: This plant can be propagated by seed or by dividing mature clumps in the spring. Seeds should be sown in the spring and will germinate in 7-10 days at a temperature of 68-77°F (20-25°C).
Cultivation Methods
The plant Ptycholobium biflorum subsp. angolensis can be cultivated both indoors and outdoors. For indoor cultivation, the plant can be potted using well-draining soil. The plant requires moderate sunlight and a temperature range of 10-30°C. Outdoor cultivation requires well-drained soil and should be planted in a spot with partial shade. This plant is drought-resistant and can withstand harsh conditions such as occasional flooding or droughts.
Watering Needs
This plant prefers a moderate amount of water, and excess watering can lead to root rot. Water the plant when the top layer of soil is dry. During the hot summer months, the plant may require more frequent watering.
Fertilization
The plant requires fertilizer twice a year, during early spring and late autumn. A balanced fertilizer with a ratio of 10-10-10 can be used to fertilize the plant. It is essential to follow the instructions on the fertilizer package to avoid over-fertilization, which can damage the plant.
Pruning
The plant requires pruning once a year to maintain its shape. Pruning should be done during the winter months when the plant has become dormant. The pruning procedure should involve trimming the plant to maintain its desired shape and to remove any dead or damaged branches. Pruning should be done using clean, sharp tools to avoid damaging the plant. Any diseased branches should be disposed of properly to prevent the disease from spreading.
Propagation of Ptycholobium biflorum subsp. angolensis
Ptycholobium biflorum subsp. angolensis can be propagated through various methods including seeds, cuttings, and layering.
Propagation by Seeds
Seeds can be collected from mature plants and used for propagation. The seeds should be sown in well-drained soil in pots or trays. The soil should be kept moist and placed in a warm, well-lit area. Germination can take up to three months. Once the seedlings have grown their first set of true leaves, they can be transplanted into individual pots.
Propagation by Cuttings
Cuttings can be taken from mature plants during the growing season. The cuttings should be taken from the softwood of the stem and should be about 10-15cm in length. Remove the lower leaves and dip the cut end in rooting hormone powder. Place the cutting in well-drained soil and keep it moist. The cutting should root in 4-6 weeks and can be transplanted into individual pots.
Propagation by Layering
Layering involves bending a stem down to the ground and burying a portion of it in soil. The buried portion of the stem will develop roots. Once roots have formed, the stem can be cut away from the parent plant and transplanted into its own pot.
Disease Management
Ptycholobium biflorum (E.Mey.) Brummitt subsp. angolensis (Baker) Brummitt can be susceptible to a variety of plant diseases, including leaf spot, powdery mildew, and bacterial wilt.
Leaf Spot: This disease is caused by a fungus and can be identified by brown or black spots on the leaves. To manage leaf spot, remove infected leaves and dispose of them properly. Fungicides may also be used to prevent the spread of the disease.
Powdery Mildew: This fungal disease appears as a white or grey powdery coating on the leaves. To manage powdery mildew, prune affected areas and dispose of them properly. Fungicides can also be used to treat infected plants.
Bacterial Wilt: This disease is caused by a bacterium and can cause wilting and yellowing of the leaves. To manage bacterial wilt, remove infected plants and dispose of them properly. Crop rotation can also help to prevent the spread of the disease.
Pest Management
Ptycholobium biflorum (E.Mey.) Brummitt subsp. angolensis (Baker) Brummitt can also be affected by various pests, including spider mites, aphids, and whiteflies.
Spider Mites: These pests are tiny, sucking insects that can cause yellowing and wilting of leaves. To manage spider mites, spray affected plants with insecticidal soap or oil. Regularly washing the plants can also help to prevent infestations.
Aphids: These insects can cause curling and wilting of leaves and can spread diseases. To manage aphids, introduce beneficial insects like ladybugs or lacewings. Insecticidal soap can also be used to treat affected plants.
Whiteflies: These pests are small, flying insects that can cause yellowing and wilting of leaves. To manage whiteflies, introduce beneficial insects like parasitic wasps or lacewings. Insecticidal soap can also be used to treat affected plants.
