Antiaris toxicaria Lesch. var. usambarensis (Engl.) C.C.Berg
Antiaris toxicaria Lesch. var. usambarensis (Engl.) C.C.Berg is a tree that belongs to the family of Moraceae and is native to Africa, specifically in the tropical and subtropical regions. It is commonly known as the Upas tree, Poison Arrow tree, and Suicide tree due to its highly toxic sap.
Appearance
The Upas tree can grow up to 45 meters tall with a trunk diameter of up to 1.8 meters. The bark is smooth and grayish-brown in color. The leaves are large, broad, and glossy, with a length of up to 50 cm and a width of up to 30 cm. The tree produces tiny flowers that grow in clusters. The fruit is a small fleshy achene with a length of up to 2 cm.
Uses
The sap of the Upas tree is highly poisonous and has been traditionally used in African culture as an arrow poison. The poison is obtained by cutting into the bark and collecting the white sap that oozes out. The sap is then applied to the arrowheads for hunting or warfare. In modern times, the sap is still used as a poison for pests in agriculture and as a source of chemicals for the production of medicines.
Beyond its toxicity, the Upas tree displays a variety of applications. The bark is effective as an insect repellent and can be used in traditional medicine to treat skin diseases, sexually transmitted infections, and digestive problems. The wood of the tree is used for furniture and construction purposes.
Growth Conditions for Antiaris toxicaria Lesch. var. usambarensis (Engl.) C.C.Berg
The Antiaris toxicaria Lesch. var. usambarensis (Engl.) C.C.Berg, commonly known as Upas or ipoh tree, grows best in tropical and subtropical climates that have a consistent high humidity. It’s a tall, evergreen tree that can reach up to 50 meters in height.
Light Conditions
The Ipoh tree requires full sun to partial shade to grow to its maximum potential. It thrives under direct sunlight when young. But as the plant grows taller and matures, it needs a more shaded disposition. If the ipoh tree is getting too much light, the leaves will turn yellow and eventually start to fall off.
Temperature Requirements
The Ipoh tree requires a warm humid environment to grow as it originates in the tropics. It can survive mild-to-moderate frosts, but only for a short time duration. It grows best when the temperature is between 22-25°C, but it can withstand temperature extremes of 10-38°C.
Soil Requirements
The Ipoh tree is not very particular about the soil texture, but it requires well-draining soil and prefers fertile, loamy soil rich in organic matter. It can grow in Sandy, loamy and clay soil, and moderately acidic to slightly alkaline soil with a pH range of 5.5-7.5. It does not do well when the soil is too sandy or too waterlogged.
Cultivation Methods
The Antiaris toxicaria Lesch. var. usambarensis (Engl.) C.C.Berg is a tropical evergreen tree that requires warm temperatures and high humidity to grow well. It's also known as the Upas tree or poison arrow tree.
Propagation of this plant is usually done through seed. The seeds are sown in a well-draining potting mix and kept moist until germination. The seedlings can be transplanted to bigger pots when they have developed 3-4 sets of leaves. The plant can also be propagated through stem cuttings, but this is not common.
The plant prefers full sun to partial shade and well-draining soil. It's important to ensure that the soil has good drainage, as the plant is susceptible to root rot.
Watering Needs
The Antiaris toxicaria Lesch. var. usambarensis (Engl.) C.C.Berg likes moist soil, and you should water it regularly. However, it's important not to over-water it, as excess water can cause root rot. The frequency of watering depends on the climate, but generally, it's advisable to water the plant every 2-3 days.
It's important to water the plant at the base and avoid getting the leaves wet. This can help prevent the spread of fungal diseases.
Fertilization
To ensure the proper growth of the Antiaris toxicaria Lesch. var. usambarensis (Engl.) C.C.Berg, it's important to fertilize it regularly. You can use a balanced, slow-release fertilizer every 4-6 weeks during the growing season. Alternatively, you can use a liquid fertilizer every 2-3 weeks.
When fertilizing the plant, avoid getting the fertilizer on the leaves, as this can cause leaf burn.
Pruning
Pruning the Antiaris toxicaria Lesch. var. usambarensis (Engl.) C.C.Berg is not necessary, but it can help maintain the plant's shape and size. The best time to prune the tree is during the growing season, as this allows the plant to heal quickly.
You can remove any dead or damaged branches, as well as any branches that are growing inward or crossing each other. It's important to use clean, sharp tools when pruning the plant, as this helps prevent the spread of diseases.
Propagation of Antiaris toxicaria Lesch. var. usambarensis (Engl.) C.C.Berg
Antiaris toxicaria Lesch. var. usambarensis (Engl.) C.C.Berg can be propagated through various methods that include:
Seed Propagation
Seeds of Antiaris toxicaria Lesch. var. usambarensis (Engl.) C.C.Berg can be collected from mature fruits. The seeds must be cleaned and planted immediately after collection. The planting medium should be well-draining and moist to support seed germination. Watering should be done to keep the soil moist, and the sowing container should be kept in a warm and shaded location.
Vegetative Propagation
Antiaris toxicaria Lesch. var. usambarensis (Engl.) C.C.Berg can also be propagated vegetatively using stem cuttings or air layering. Stem cuttings should be taken from mature stems of the plant, ideally in the spring or early summer. The cuttings should be dipped in rooting hormone and planted in a well-draining soil mix. The soil should be kept moist to support root development. Air layering involves making a small cut on a mature stem, wrapping it in moist sphagnum moss, and then covering it with plastic wrap. The moss should be kept moist until roots develop, after which the stem can be cut and potted in a well-draining potting mix.
Disease Management
Antiaris toxicaria Lesch. var. usambarensis is susceptible to various diseases that can cause yield losses if not managed properly. Common diseases that affect the plant include:
- Anthracnose: This is a fungal disease that attacks the leaves, stems, and fruits of the plant. It causes the plant to have brownish spots and holes on the affected parts. You can manage anthracnose by pruning the affected parts and applying fungicides.
- Root Rot: It's a soil-borne fungal disease that affects the roots of the plant, causing them to rot. This may be caused by overwatering, poor soil drainage, or waterlogging. You can prevent root rot by ensuring that the soil is well-drained and avoiding overwatering.
- Powdery Mildew: This is a fungal disease that causes white powdery patches on the leaves, stems, and flowers of the plant. To control powdery mildew, you can remove the infected parts and apply fungicides.
Pest Management
Antiaris toxicaria Lesch. var. usambarensis is also vulnerable to pest infestations that may cause damage to the plant. Common pests that affect the plant include:
- Mealybugs: These soft-bodied insects suck the sap from the plant, causing yellowing of the leaves. You can control mealybugs by removing the affected parts and applying insecticides.
- Mites: These are small insects that cause discoloration and distortion of the leaves. Mites multiply quickly and can cause extensive damage. You can manage mites by removing the affected parts and applying miticides.
- Caterpillars: These insects can cause defoliation of the plant as they feed on the leaves. You can control caterpillars by manually removing them or using organic insecticides.
Regular monitoring of the plant can help detect any signs of disease or pest infestation at an early stage, making it easier to manage. It's also important to maintain favorable growing conditions, such as proper watering and fertilization, to help the plant resist diseases and pests.
