Plant Description
Dacryodes osika, also known as Osika, is a commonly found plant in Southeast Asia, particularly in Papua New Guinea. This plant belongs to the Burseraceae family and is an evergreen tree that can grow up to 25 meters in height.
Common Names
Osika is known by various common names in different regions. In Papua New Guinea, it is called "aksin" by the Yimas people, while the Kalam language name is "amu". In Pidgin, the lingua franca of the country, it is known as "kampanin" or "korosu". In Malaysia, it is known as "meranti jerit" or "meranti susu". In Indonesia, the Melayu language name of the tree is "lampas" or "lampes".
Uses
The Osika tree is important to many indigenous communities for various purposes. The resin from the tree has been used for medicinal and ceremonial purposes. The wood of the tree is used for construction, cabinetry, and carving. Its bark can be used to make ropes, and the leaves are employed to make baskets and other handicrafts. Additionally, the fruit of the tree is edible and is a source of food for many animal species.
General Appearance
The Osika tree has a straight trunk and a rounded crown that can grow up to 12 meters in diameter. The tree has a smooth, grey-colored bark that becomes rough and scaly with age. The leaves are elliptical in shape, pointed at the tip, and grow up to 20 centimeters in length. The flowers of the Osika tree are small and yellowish-green and grow in clusters. The fruit is a round drupe, about 2 centimeters in diameter, with a hard, woody shell that encloses an edible, oily pulp. The fruit turns from green to yellow when it ripens.
Growth Conditions of Dacryodes osika
Dacryodes osika (Guillaumin) H.J.Lam, commonly known as Osika, is a tree species that is native to the Pacific islands. The tree is commonly found in lowland rainforests and is known to grow up to 50 meters tall in favorable conditions.
Light Requirements
Dacryodes osika typically grows in areas with high light intensity. However, the plant can also grow well in areas with partial shade. It is essential to ensure that the plant is not exposed to direct sunlight when it is still young. The tree can grow well in both direct and indirect sunlight as it matures.
Temperature Requirements
The plant can grow well in a wide range of temperatures. Dacryodes osika prefers temperatures between 20°C and 30°C, and it cannot tolerate temperatures below 10°C. The plant cannot also withstand extreme temperature fluctuations, and it is essential to provide a stable environment.
Soil Requirements
The plant can grow well in sandy, loamy, and clayey soils. However, the soil should be well-draining to prevent waterlogging. The plant prefers slightly acidic to alkaline soils with a pH of between 5.5 - 8.0. Adding organic matter to the soil can improve its overall structure and nutrient content, making it favorable for Dacryodes osika growth.
Cultivation Method for Dacryodes Osika (Guillaumin) H.J.Lam
Dacryodes osika, commonly known as Katopa, is a tropical tree species found primarily in Oceania. If you plan to cultivate D. osika, it is essential to follow some procedures. First, choose an area with a minimum temperature of around 20°C. This plant thrives best in tropical climates with high humidity levels.
Ensure the soil has good drainage capabilities and a pH range from 6.5 to 7.5. It is better to have silty soils for this plant. When you start the plantation, ensure that the hole is at least one meter deep and remove all the debris from it.
Watering Needs for Dacryodes Osika (Guillaumin) H.J.Lam
Watering your Dacryodes osika regularly is vital for its growth and survival. During dry weather conditions, water the plant every two days. Make sure you water the base of the plant to avoid wetting its foliage. You should also be careful not to overwater the tree. Overwatering can cause root rot and invite pests to the plant.
Fertilization for Dacryodes Osika (Guillaumin) H.J.Lam
Fertilizing the plant during its vegetative growth stage is a crucial practice. Use nitrogen-based fertilizers, blood and bone, or a potassium-based fertilizer. Fertilize twice a year, once during the rainy season and once in the middle of the dry season.
It is essential to pace the use of fertilizers to prevent toxicity or other negative effects on the plant's health. Too much fertilizer can lead to a decrease of the plant's fruit yield and quality.
Pruning for Dacryodes Osika (Guillaumin) H.J.Lam
Pruning is essential for Dacryodes osika to shape the plant and ensure proper fruit production. Begin pruning the plant during the rainy season to stimulate its growth. Prune any diseased or damaged branches as soon as possible.
Also, trim any branches that block sunlight from reaching the plant's interior. You should prune during the dry season after the fruiting period is over. Do not prune during the fruiting period as it can affect the yield.
Propagation Methods for Dacryodes osika
Dacryodes osika, commonly known as 'African pear' or 'bush butter tree', is a tropical fruit tree native to Africa. It is primarily propagated by seeds but can also be propagated by vegetative means.
Seed Propagation
The most common and easiest method of propagating Dacryodes osika is through seeds. Seeds are usually collected from healthy and mature fruits. The seeds should be cleaned and air-dried in a shaded area to allow for good germination rates. After that, the seeds can be stored in a cool, dry place until planting.
The seeds should be sown in seedling trays filled with fertile soil. The trays should be placed in a shaded area and watered regularly. Germination usually takes place within 3-4 weeks. When the seedlings are large enough, they can be transplanted into individual pots or into the field.
Vegetative Propagation
Dacryodes osika can also be propagated vegetatively. This method is generally used to propagate selected cultivars or for large-scale propagation. The following are the vegetative propagation methods:
Stem Cuttings
Stem cuttings are taken from healthy trees in the rainy season. Cuttings should be about 30-40 cm in length and contain at least two nodes. The cuttings should be treated with growth hormones before planting them in a rooting medium. After rooting, the cuttings can be transplanted into individual pots or into the field.
Air Layering
Air layering involves creating a small wound on a stem and then packing the wound with a rooting medium. The wound should be wrapped with a plastic bag to retain moisture. After some weeks, roots will grow from the wound, and the rooted portion can be severed from the parent tree and transplanted.
Budding and Grafting
Budding and grafting involve joining a scion onto a rootstock. This method is quite tricky and requires professional knowledge. It is generally used for the production of selected cultivars.
Regardless of the propagation method used, care should be taken to ensure that the seedlings or vegetatively propagated plants are healthy before transplanting them into the field.
Disease and Pest Management of Dacryodes osika
Dacryodes osika (Guillaumin) H.J.Lam, commonly known as African pear, is a tropical evergreen tree that produces a nutritious fruit. However, like any other plant, it is prone to various diseases and pests that can reduce its yield and quality. It is essential to manage these problems to ensure healthy plant growth and maximum yield. Here are some of the common diseases and pests that might affect Dacryodes osika and ways to manage them.
Common Diseases
1. Powdery Mildew: Powdery mildew is a fungal disease that appears as white or gray powdery patches on leaves, stems, and fruit. It is caused by the fungus Oidium sp. The disease affects the photosynthesis process and reduces the growth of the plant.
Management: To manage powdery mildew, it is advisable to prune the infected part of the plant and avoid overhead watering. Use a fungicide to control the spread of the disease. Additionally, provide adequate spacing between the plants to increase air circulation.
2. Anthracnose: Anthracnose is a fungal disease that appears as circular brown spots on leaves, stems, and fruits. The disease is caused by the fungus Colletotrichum sp. Infected fruits have sunken black spots that lead to rotting and falling off.
Management: Control anthracnose by pruning infected parts of the plant and avoiding overhead watering. Use a fungicide to control the spread of the disease. Additionally, provide adequate spacing between plants to increase air circulation.
Common Pests
1. Fruit flies: Fruit flies are small insects that can cause significant damage to the fruits of Dacryodes osika. The insects lay eggs in the fruits, leading to fruit rotting.
Management: Control fruit flies by keeping the orchard clean and free of decaying fruits. Use bait traps or biological control methods to manage the insects.
2. Mealybugs: Mealybugs are pests that appear as white, waxy masses on the leaves and stems of plants. They suck the sap from the plant, leading to stunted growth and reduced yield.
Management: Control mealybugs by pruning the affected parts of the plant and using insecticidal soap. Additionally, introduce natural predators such as ladybugs and lacewings to control the population of mealybugs.
In conclusion, managing diseases and pests is essential for healthy growth and maximum yield of Dacryodes osika. Preventive measures such as maintaining clean orchards, providing adequate spacing, and avoiding overhead watering can help minimize the incidence of diseases and pests. In case of an outbreak, use appropriate control measures such as pruning, fungicide application, and biological control methods to manage the problem.
