Overview:
Lannea obovata (Hook.f. ex Oliv.) Engl., also known as the Marula tree, is a medium-sized tree belonging to the Anacardiaceae family. The plant is native to tropical regions of Southern Africa, Angola, Zimbabwe, and Mozambique. It is commonly found in the savannah regions and woodlands.
Description:
Lannea obovata is a deciduous tree that can grow up to 20 meters tall. Its bark is grayish-brown and rough with deep vertical grooves, and the trunk is usually straight and cylindrical. The leaves are simple, alternate, and obovate with a dark green upper surface and paler green underside. The flowers are small, yellowish-green, and grow in clusters towards the end of the branches, while the fruit is a drupe that is reddish-brown when ripe.
Uses:
The Marula tree has various uses in traditional medicine. The bark, leaves, and roots are used to treat several ailments, including diarrhea, fever, malaria, and stomach aches. The fruit is used to make a popular alcoholic beverage, Marula beer, which has a strong, sweet and creamy taste and is known for its high alcohol content.
Lannea obovata also has significant economic value. The fruit is commercially harvested for its oil, which is rich in oleic acid and is used in cosmetics and skin care products. In addition, the wood is used for making furniture, carvings, and fuelwood, while the bark is a source of tannins used in the leather industry.
General Appearance:
The Marula tree has a distinctive shape, with a wide-spreading crown that provides ample shade. The tree's leaves drop during the winter months, exposing the smooth grayish-brown bark that's deeply grooved. The yellowish-green flowers appear in late spring, and the fruit ripens in summer, usually between December and March. The plant's unique aesthetics have made it a sought-after tree for landscaping and ornamental purposes.
Light Requirements
Lannea obovata typically grows in areas with full sun exposure, although it can also tolerate partial shade. An ample amount of sunlight is necessary for the plant's growth and development. Therefore, it should be placed in an area with enough exposure to sunlight, mostly in the morning and afternoon, to thrive.
Temperature Requirements
The plant grows well in tropical and subtropical regions where the temperature ranges from 20 to 34 degrees Celsius. Lannea obovata is susceptible to frost, so it should be kept in a warm environment, preferably not below 15 degrees Celsius, especially during the winter. The plant’s temperature demands are not too strict, but it prefers a warm environment.
Soil Requirements
The plant grows in fertile and well-drained soils that are rich in organic matter. Lannea obovata can tolerate a pH range of 5.0-7.5, but it prefers slightly acidic soils. The soil should be sandy or loamy, with good water retention capacity to retain adequate moisture levels. It is advisable to add organic matter such as compost to improve soil fertility and drainage.
Cultivation Methods
Lannea obovata (Hook.f. ex Oliv.) Engl. is a deciduous tree that grows best in tropical regions, typically found in savannas, open woodlands, and along riverbanks. If you are planting from seed, start by selecting an area with well-drained soil and plenty of sunlight.
First, soak the seeds in water overnight. Then, you can plant them directly into the ground, as this tree species has a taproot and doesn't transplant well. Make sure to water them regularly until they germinate in about 2-3 weeks. Once the tree is established, it doesn't need frequent watering, and you can rely solely on natural rainfall.
This species is relatively easy to cultivate, and while it doesn't require high maintenance, it does benefit from regular pruning. Pruning helps create a canopy that helps shield the tree from the harsh sun.
Watering Needs
Once established, Lannea obovata doesn't require frequent watering. Instead, you can rely on natural rainfall to keep the soil moist. However, during the first few weeks of growth, it is important to keep the seedlings consistently moist. Water them every 3-4 days, but don't saturate the soil.
If you live in an area with a dry climate, you may need to water the tree more frequently. Monitor the soil, and water when the top 2-3 inches become dry. It is better to water deeply once a week rather than shallowly every day.
Fertilization
Lannea obovata doesn't require heavy fertilization, but applying a slow-release fertilizer once a year may help enhance the tree's growth. You can apply it in the spring or early summer before new growth begins. Choose a balanced fertilizer such as a 10-10-10 or 14-14-14 blend, and read the package instructions carefully to avoid overfertilization.
Alternatively, you can use organic compost or manure to fertilize the tree. Spread a layer of compost or manure around the tree's drip line, or mixed it into the soil. Do this once a year, and water the soil afterward to help the nutrients absorb into the soil.
Pruning
Pruning helps keep Lannea obovata healthy and promotes its growth. It is best to prune the tree during the dormant season, i.e., winter. Start by removing deadwood and damaged branches, as these can be entry points for pests and diseases. Next, remove any crossing branches or those that may be growing too close together.
You can also control the tree's height and shape by selectively pruning the branches. For extensive pruning, avoid cutting too much at one time, and spread it out over a few years to prevent shocking the tree. Always use sharp and clean pruning tools to ensure clean cuts and prevent the spread of diseases.
Propagation of Lannea obovata
Lannea obovata (Hook.f. ex Oliv.) Engl., also known as the "umbrella tree," is a plant species native to Africa. It is a popular tree for its medicinal, cultural, and ecological value. Lannea obovata is propagated by various methods, including:
Seed Propagation
Propagation by seeds is the most common method used for Lannea obovata. Seeds can be obtained from ripe fruits, which are often dropped from the tree. After collecting the seeds, they are cleaned to remove any attached fibers or fruit pulp. The seeds are then sown in seed trays filled with a mixture of sand and soil. The trays are kept moist and placed in a shaded area. Germination may take place within two weeks.
Vegetative Propagation
Vegetative propagation can be done through different methods such as grafting, rooting of cuttings or tissue culture. Grafting is done by taking a scion from a mature tree and attaching it onto a young rootstock. With the use of rooting hormones, cuttings can also be used for propagation. Tissue culture, on the other hand, involves taking small pieces of plant tissues and growing them in a laboratory using special media and procedures to produce multiples of identical plants.
Air Layering
Air layering is another method for propagating Lannea obovata. This method involves peeling a section of bark from a branch and applying rooting hormone to the exposed area. The area is then covered with a moist substance such as sphagnum moss, wrapped with plastic and, secured in place. Once roots have developed, the section of the branch can be cut just below the roots, and the new plant is ready for planting in the soil.
Propagation of Lannea obovata can be time-consuming, but with proper care and attention, it can lead to the production of a great number of healthy plants suited for any environment.
Disease and Pest Management for Lannea obovata
Lannea obovata (Hook.f. ex Oliv.) Engl., commonly known as the African lannea, is a popular plant that is used widely for various purposes including its medicinal properties. Although the African lannea is relatively hardy, it is not immune to diseases and pests. In this article, we will discuss some of the common diseases and pests that might affect the plant, and suggest ways to manage them.
Common Diseases Affecting Lannea obovata
The African lannea is susceptible to a number of diseases, some of which include:
- Leaf spots: Leaf spots are common on Lannea obovata and can be caused by fungi or bacteria. The spots can vary in size and shape, but they often start as small dots and grow into larger spots. Leaf spot can be managed by pruning and disposing of the affected leaves.
- Root rot: Root rot is a serious fungal disease that affects the roots of the plant, causing them to rot. It is usually caused by poor drainage, overwatering, or a fungal infection. The disease can be managed by improving drainage and reducing the frequency of watering.
- Anthracnose: Anthracnose is a fungal disease that affects the leaves, stems, and fruit of the African lannea. It can cause wilting, leaf drop, and defoliation. The disease can be managed by pruning and disposing of the affected parts of the plant.
Common Pests Affecting Lannea obovata
The African lannea can also be affected by a number of pests, some of which include:
- Mealybugs: Mealybugs are small, soft-bodied insects that can be found on the leaves and stems of the plant. They secrete a sticky substance that attracts other insects and can cause leaf drop. Mealybugs can be managed by manually removing them from the plant and using insecticidal soap.
- Aphids: Aphids are small, soft-bodied insects that can also be found on the leaves and stems of the African lannea. They feed on the sap of the plant and can cause wilting and leaf drop. Aphids can be managed by manually removing them from the plant and using insecticidal soap.
- Caterpillars: Caterpillars are the larvae of butterflies and moths, and they can feed on the leaves of the African lannea. They can cause defoliation and damage to the plant. Caterpillars can be managed by manually removing them from the plant or using Bacillus thuringiensis (BT) insecticide.
In conclusion, the African lannea is a hardy plant but can still be affected by diseases and pests. Proper management practices such as pruning and disposing of affected parts of the plant, improving drainage, reducing the frequency of watering, manually removing pests, and using insecticides can help prevent or manage diseases and pests on Lannea obovata.
