Overview
Olea subtrinervata Chiov. is a plant species belonging to the Oleaceae family. It is also known by its common name, the East African Olive. This plant is native to eastern Africa, particularly in Kenya and Tanzania.
Appearance
The East African Olive is a small evergreen tree that grows up to 6 meters tall. Its leaves are shiny and oval in shape with a pointed tip, measuring between 5-12 cm long. The venation pattern on the leaves is very distinct, with three prominent veins stemming from the base of the leaf. The tree also produces small white or cream-coloured flowers that bloom during spring and summer and are followed by small, fleshy, purple or black fruits.
Uses
The East African Olive is not commonly cultivated, but its wood is used for fuel and charcoal production, and the leaves and bark have been used in traditional medicine to treat various ailments such as malaria, coughs, and fever. The oil from the fruit is edible but is not commonly used due to the small size and low yield of the fruits.
Light Requirements
Olea subtrinervata Chiov. grows well under conditions of full sun exposure. It requires a minimum of six hours of sunlight per day for optimal growth, which means planting in an area with ample exposure to sunlight is crucial.
Temperature Requirements
The temperature requirements of Olea subtrinervata Chiov. are moderate. It thrives well under temperatures between 10°C to 30°C, making it suitable for planting in tropical and subtropical regions. The plant is hardy enough to withstand brief periods of frost, but it grows best in frost-free climates.
Soil Requirements
Olea subtrinervata Chiov. prefers well-draining soils rich in organic matter. The ideal soil is sandy loam or loam soil, which provides an excellent balance of water retention and drainage. The pH of the soil should range between 6.5 and 7.5 for optimal growth. It is also important to note that the plant is sensitive to waterlogged soils, which can lead to root rot.
Moreover, it requires a regular supply of water and tolerates extended periods of drought. Therefore, planting in an area that receives moderate rainfall or regular irrigation is advisable. The addition of organic matter to the soil improves its water retention capability, which allows for better plant growth and development.
Overall, providing ample sunlight, moderate temperatures, and well-draining soils with suitable pH and water content are key growth conditions for the plant Olea subtrinervata Chiov.
Cultivation Methods
Olea subtrinervata Chiov. is a plant that requires a semi-arid climate and is best cultivated in warm regions. It requires well-drained soils with good aeration and light texture, but can also tolerate sandy soils. The ideal soil pH for this plant is slightly acidic to neutral. The plant can be propagated through seed or cuttings. It does not require too much care and can thrive in low-fertility soils.
Watering Needs
The plant requires moderate watering and is best irrigated when the soil is dry to the touch. Overwatering can cause root rot, which can lead to the death of the plant. During the dry season, the plant should be watered once or twice a week, depending on the climate and soil type. The plant can also withstand periods of drought and can recover once the rains come.
Fertilization
Fertilization should be done sparingly as the plant can thrive in low-fertility soils. However, the plant can benefit from nitrogen fertilizers, especially during the growth stage. Fertilization should be done after the first flush of new growth. Too much fertilizer can cause excessive growth and lead to an unproductive plant.
Pruning
Olea subtrinervata Chiov. requires little pruning, but it is important to remove dead or diseased branches to promote healthy growth. Pruning should be done during the dormant season to minimize the risk of injuring the plant. The plant can also be pruned to maintain a desirable shape and size. However, pruning should never be done during the flowering stage as it can reduce fruit production.
Propagation of Olea subtrinervata Chiov.
Olea subtrinervata Chiov. can be propagated by different methods such as seed propagation, cutting propagation, and grafting.
Seed propagation
Seed propagation is the most common method used for propagating Olea subtrinervata Chiov. However, the plant does not produce fruit every year, making it challenging to collect the seeds.
When collecting seeds, ensure that they are mature and viable. The seeds can be sown directly in the field or in a nursery bed. For the best results, use well-draining soil and ensure that the soil is moist but not waterlogged.
Germination usually occurs within 3-4 weeks after sowing. Once the seedlings reach a height of 10cm, they can be transplanted into individual bags or pots for further growth.
Cutting propagation
Cutting propagation is another method of propagating Olea subtrinervata Chiov. Cuttings can be taken from mature plants in autumn or spring.
Remove a 15-20cm long cutting with at least three nodes. Dip the base of the cutting in a rooting hormone, and then plant the cutting in a container filled with well-draining soil. Ensure that the soil is kept moist but not waterlogged.
The cutting should start rooting within 2-3 weeks. When the roots are well-developed, transplant the cutting into individual bags or pots.
Grafting
Grafting is another viable method for propagating Olea subtrinervata Chiov. This method is preferable for propagating cultivars and improving the growth of seedling plants.
To graft, use a one-year-old rootstock and a scion that is taken from the previous season's growth. Ensure that both the rootstock and scion have the same diameter, and then splice them together.
The grafted plants should be kept in a shaded area and watered regularly until they start actively growing.
Disease Management for Olea subtrinervata Chiov.
Olea subtrinervata Chiov. is susceptible to a few common diseases such as:
Phytophthora Root Rot
Phytophthora root rot is a fungal disease that causes root rot and stem cankers in Olea subtrinervata Chiov. plants. It thrives in waterlogged conditions and can cause significant damage to the plant if left untreated. To manage this disease, avoid overwatering and improve drainage. Fungicides like mefenoxam and metalaxyl can also be applied.
Verticillium Wilt
Verticillium wilt is a fungal disease caused by Verticillium dahliae which attacks leaves, foliage, and stems of Olea subtrinervata Chiov. plants. It causes wilting, discoloration and stunted growth of the plant. To manage this disease, remove infected plants and avoid planting Olea subtrinervata Chiov. in soil that previously grew other crops which are prone to Verticillium wilt. Fungicides like thiophanate-methyl can also be used to control the spread of this disease.
Pest Management for Olea subtrinervata Chiov.
Olea subtrinervata Chiov. is also vulnerable to a few pests such as:
Oleander Caterpillar
Oleander caterpillars are voracious feeders that cause severe defoliation of Olea subtrinervata Chiov. plants. To manage this pest, remove caterpillars by handpicking and destroying them. Insecticides containing Bacillus thuringiensis can also be used to control infestations.
Dusky-Footed Woodrat
The dusky-footed woodrat is a rodents species that may cause significant damage to the root system of Olea subtrinervata Chiov. plants. To manage this pest, erect barriers such as metal mesh or hardware cloth around the root zone of the plant. Also, avoid leaving clippings or debris from pruning close to the plant which could provide a perfect habitat for woodrats.
By following these management practices, you can successfully protect your Olea subtrinervata Chiov. plant from infections and damages caused by diseases and pests.
