Overview
Lannea schweinfurthii (Engl.) Engl. var. stuhlmannii (Engl.) Kokwaro is a deciduous tree species that is native to Africa. It belongs to the Anacardiaceae family, which includes cashews and mangoes. Lannea schweinfurthii var. stuhlmannii is an important plant for both medicinal and economic purposes.
Appearance
The tree can grow up to 15 meters tall and has a distinct brownish-grey bark with deep vertical fissures. The leaves are compound and alternate, consisting of 5 to 9 leaflets that are 6–20 cm long. The tree produces small yellow flowers, and the fruit is a drupe with a hard stone containing a single seed.
Common Names
Lannea schweinfurthii var. stuhlmannii is commonly known as the African grapefruit, Msamba in Swahili, and Ntcheya in Chichewa.
Traditional Uses
The tree has been used for centuries in traditional African medicine to treat various ailments. The bark is used as a remedy for dysentery, diarrhea, and fever. The roots and leaves are also used to stimulate appetite and relieve pain and inflammation. Additionally, the tree produces a resin that is used to treat skin disorders and wounds.
Economic Uses
The fruit of Lannea schweinfurthii var. stuhlmannii is edible and has a sweet and sour taste. It is commonly eaten raw or used to make jams and jellies. The wood of the tree is used for construction, fuelwood, and charcoal production. The tree also plays an important role in ecological conservation as it is used in reforestation programs and has the ability to enrich soil fertility.
Light Requirements
Lannea schweinfurthii var. stuhlmannii prefers full sun to partial shade for optimal growth. It needs a minimum of six hours of direct sunlight exposure every day to thrive.
Temperature Requirements
The plant can grow in a wide range of temperatures. However, it prefers warm temperatures. The optimal temperature for growth is between 20°C and 30°C. Temperatures below 10°C and above 40°C can have adverse effects on the plant's growth and development.
Soil Requirements
Lannea schweinfurthii var. stuhlmannii prefers well-drained soils with a pH range of 6.0 to 7.5. The soil should not be waterlogged as the plant cannot withstand water-saturated conditions. It can grow well in various types of soils, including sandy loam, loam, and clay loam soils. The addition of organic matter to the soil can improve its growth and productivity.
Cultivation Methods
The Lannea schweinfurthii (Engl.) Engl. var. stuhlmannii (Engl.) Kokwaro plant prefers well-drained soil and a sunny location. It can tolerate drought but not frost, so it should be kept in a warm and dry location during the winter months.
The plant can be propagated through both seeds and cuttings. Seeds should be sown in well-draining soil about 1 cm deep and kept moist until germination, which takes approximately two weeks. Cuttings should be taken from mature plant stems and planted in well-draining soil with a rooting hormone to encourage growth.
Watering Needs
The Lannea schweinfurthii (Engl.) Engl. var. stuhlmannii (Engl.) Kokwaro plant requires moderate amounts of water. It should be watered deeply once a week during the growing season, and the soil should be allowed to dry out slightly between waterings. Overwatering can lead to root rot and other problems.
Fertilization
The Lannea schweinfurthii (Engl.) Engl. var. stuhlmannii (Engl.) Kokwaro plant benefits from regular fertilization during the growing season. A balanced fertilizer with equal parts nitrogen, phosphorus, and potassium can be applied every four weeks. Fertilization should be reduced or even stopped during the winter months.
Pruning
The Lannea schweinfurthii (Engl.) Engl. var. stuhlmannii (Engl.) Kokwaro plant can benefit from occasional pruning to maintain its shape and size. Pruning should be done in early spring before new growth begins. Dead or damaged branches should be removed, and the plant can be lightly trimmed to encourage new growth.
Propagation of Lannea schweinfurthii var. stuhlmannii
Lannea schweinfurthii (Engl.) Engl. var. stuhlmannii (Engl.) Kokwaro is a deciduous tree that is native to Kenya, Tanzania, and Uganda. It is commonly known as the "Gum-Myrrh tree" and is used for its medicinal properties.
Seed Propagation
The most common method of propagating Lannea schweinfurthii var. stuhlmannii is through seed propagation. The seeds are collected from mature trees during the dry season. The collected seeds are then soaked in water overnight to soften the seed coat, which facilitates germination.
After soaking, the seeds are sown in prepared seedbeds at a depth of 1-2 cm. The seedbeds should be kept moist to encourage germination. Germination can take up to 6-8 weeks and the resulting seedlings should be left to grow for up to two years before transplanting them to their permanent location.
Cuttings Propagation
Lannea schweinfurthii var. stuhlmannii can also be propagated through cuttings. Cuttings should be taken during the dry season when the tree has shed its leaves. Semi-hardwood cuttings of 20-30 cm in length can be used. The cuttings should be treated with rooting hormone and inserted into a rooting medium. The rooting medium should be kept moist and the cuttings should be kept in a shaded area to prevent wilting.
Rooting can take up to 3-4 weeks. Once the cuttings have rooted, they can be transplanted into their permanent location.
Air Layering
Air layering is another method that can be used to propagate Lannea schweinfurthii var. stuhlmannii. This method involves making a ring of bark around a branch of the tree and applying rooting hormone to the exposed wood. A plastic bag is then wrapped around the area to keep it moist. Roots should develop within 3-4 weeks. Once the roots have developed, the branch can be cut off and planted in its permanent location.
Disease Management
There are several diseases that could affect Lannea schweinfurthii var. stuhlmannii. One of the most common ones is fungal leaf spot. This disease usually appears as brown spots on the leaves that eventually turn yellow and drop off. To manage this disease, remove infected leaves immediately and destroy them to prevent further spreading. Also, provide good air circulation, avoid overcrowding, and water the plant at the base to keep the leaves as dry as possible.
Another common disease that affects Lannea schweinfurthii var. stuhlmannii is powdery mildew. This disease appears as a white, powdery substance on the leaves and stems. To manage powdery mildew, increase air circulation, keep the plant dry, and avoid overhead watering. Additionally, you can apply fungicides to prevent further development of this disease.
Pest Management
Several pests can affect Lannea schweinfurthii var. stuhlmannii, including aphids, mealybugs, and spider mites. Aphids are small, pear-shaped insects that feed on the sap of the plant, causing the leaves to curl and distort. To manage aphids, you can spray the plant with a mild soap and water solution or apply insecticides. Mealybugs are small, white insects that produce a waxy coating, making them hard to detect. To manage mealybugs, you can remove them with a cotton swab dipped in alcohol or apply insecticides.
Spider mites are tiny pests that feed on the underside of leaves, leaving small, white spots. To manage spider mites, you can spray the plant with a strong blast of water to dislodge them or apply insecticides. It is important to monitor the plant regularly and address any pest problems as soon as they arise to prevent significant damage.
