Overview of Aralia elata (Miq.) Seem.
Aralia elata, also referred to as Japanese angelica tree, is a deciduous perennial plant that belongs to the family Araliaceae. The plant is native to Eastern Asia, particularly to China, Korea, and Japan. It is widely cultivated for its medicinal and ornamental values. The plant is named Aralia elata due to its remarkable size and beauty.
Appearance of Aralia elata
The Aralia elata typically grows to a height of 6 to 15 meters, with a spread of up to 4 meters. The plant's stem is characterized by a grey or brownish bark covered with sharp spines that deter herbivores. The leaves are large, with a length of up to 60 centimeters, and have a distinct bipinnate shape. The flowers of the plant are produced on stalks that grow from the axils of the leaves. The flowers are small, greenish-white, and arranged in large compound umbels that can measure up to 60 centimeters in diameter, while the fruit measures around 6 mm in diameter and turns a purplish-black color when mature.
Common Names of Aralia elata
Aralia elata is commonly known as Japanese angelica tree, Chinese angelica tree, Angelica-tree, Devil's Walking Stick, and Japanese Aralia.
Uses of Aralia elata
The Aralia elata has various medicinal and ornamental uses. In traditional medicine, the plant's root, stem, and leaves are used to treat a variety of ailments, including rheumatoid arthritis, fever, coughs, colds, and headaches. The plant also contains saponins, flavonoids, and polysaccharides, which provide an anti-inflammatory and immune-boosting property.
The plant's ornamental values are due to its towering stature, large leaves, and exotic flowers. The plant is commonly cultivated as a visual interest in gardens, parks, and streetscapes. Because of its aesthetics and hardiness, the plant is often used in forest restoration projects due to its ability to thrive in a variety of soil types and tolerate pollution.
Growth Conditions for Aralia elata (Miq.) Seem.
Light: Aralia elata (Miq.) Seem. prefers partial to full shade. Direct sunlight can burn the leaves and cause damage to the plant. In shaded areas, the plant grows taller and has larger leaves.
Temperature: This plant is hardy to USDA zones 3-8 and can tolerate a wide range of temperatures. However, it prefers cool temperatures and can withstand extreme cold temperature (-22°F). It is best suited to regions with cool winters and mild summers.
Soil requirements: Aralia elata (Miq.) Seem. prefers well-drained soils that are rich in organic matter. It can grow well in a range of soil types, including loam, clay, and sand. But, the soil should be acidic to slightly acidic with a pH range of 5.0-6.5. Consistent moisture is necessary for optimal growth and the soil should be kept consistently moist but not waterlogged.
Cultivation Methods
Aralia elata prefers full sun to partial shade conditions for optimal growth. The plant can tolerate a wide range of soil types, but it thrives in well-draining, moist, and fertile soils. It is best to plant the Aralia elata in spring or fall.
The root ball should be soaked in water for an hour before planting. Dig a hole twice the size of the root ball and add organic matter to the soil. Place the plant in the hole and fill the hole with soil. Water the plant thoroughly and add mulch around the base to conserve moisture.
Watering Needs
Aralia elata requires consistent moisture to flourish. It is essential to water the plant deeply and regularly, especially during dry spells. The frequency of watering can be reduced in the winter months to avoid waterlogging the roots.
However, prolonged drought can cause leaf drop and stunted growth in the plant. Mulching around the base helps retain moisture and regulate the soil temperature.
Fertilization
Applying a balanced fertilizer during the growing season stimulates healthy growth and blooming in Aralia elata. It is best to fertilize the plant in early spring before new growth emerges.
Follow the manufacturer's instructions on the application rate and frequency. Avoid over-fertilization as it can lead to excessive leaf growth and reduce blooming in the plant.
Pruning
Aralia elata generally requires minimal pruning. However, removing the spent blooms and dead or damaged stems promotes healthy growth and prolongs the blooming season.
It is best to prune the plant in late winter or early spring before new growth emerges. Use clean and sharp pruning tools to avoid damaging the plant. Cut the stem above a leaf bud or a side shoot to encourage branching and bushier growth in the plant.
Propagation of Aralia elata (Miq.) Seem.
Aralia elata (Miq.) Seem. commonly known as Japanese angelica tree is propagated through seeds and vegetative methods such as cuttings and layering.
Propagation by Seeds
Seeds should be collected from the fruit when it turns black and sows immediately as they have a short viability period and can lose viability quickly. Seeds can be sown directly into pots or seedbeds after removing the thin layer of pulp. The pots or seedbeds should be kept in a partially shaded area with well-drained soil and moderate moisture. The germination of seeds takes around two to four weeks.
Propagation by Cuttings
The stem cuttings of Aralia elata (Miq.) Seem. can be taken during early summer or early autumn. The stems should be cut into pieces that have two or three nodes, and the leaves on the lower part of the stem should be removed. The cuttings should be dipped in rooting hormone powder and planted in soil mixed with sand or perlite. The soil should be kept moderately moist and kept in a partially shaded area. The roots of the cutting will develop in around six to eight weeks.
Propagation by Layering
Aralia elata (Miq.) Seem. can also be propagated by layering, which is done in early spring or late summer. A low branch of the plant is selected, and the stem should be scraped slightly where the branch touches the ground. The scraped area should be covered with soil and held in place with a peg. The layered stem should be kept moist, and after the root system has developed, it should be cut from the main plant and transplanted.
Disease and Pest Management for Aralia elata (Miq.) Seem.
Aralia elata (Miq.) Seem., commonly known as Japanese angelica tree or devil's walking stick, is a tall, deciduous shrub or small tree, native to East Asia. It is a popular ornamental plant due to its attractive foliage and unique appearance. However, like any other plant, Aralia elata is also susceptible to various pests and diseases.
Common Diseases Affecting Aralia elata
Some of the common diseases affecting Aralia elata are:
- Leaf spot: This disease is caused by several fungi and results in yellowing and browning of leaves with black or brown spots. To manage the disease, it is recommended to remove and destroy infected leaves and maintain proper sanitation practices.
- Powdery mildew: Powdery mildew is a fungal disease that causes a whitish coating on the leaves, stems, and flowers of the plant. To manage the disease, it is recommended to prune infected plant parts and ensure good air circulation around the plant.
- Rust: Rust is a fungal disease that results in reddish-brown spots on the leaves and stems of the plant. To manage the disease, it is recommended to remove and destroy infected leaves and avoid overhead watering.
Common Pests Affecting Aralia elata
Some of the common pests affecting Aralia elata are:
- Aphids: Aphids are small, sap-sucking insects that can cause stunted growth, yellowing of leaves, and distortion of shoots. To manage aphids, it is recommended to wash them off with a strong stream of water or use insecticidal soap.
- Spider mites: Spider mites are tiny, spider-like pests that feed on the undersides of leaves, causing discoloration and wilting. To manage spider mites, it is recommended to wash the leaves with water or use insecticidal soap.
- Scale insects: Scale insects are small, immobile pests that attach themselves to the leaves and stems of plants, causing yellowing and weakening of the plant. To manage scale insects, it is recommended to prune and destroy infected parts of the plant and use horticultural oil.
Regularly inspecting the plant for any signs of pest or disease and maintaining good sanitation practices can go a long way in preventing and managing any problems that may arise. It is also recommended to consult with a professional gardener or horticulturist for further advice and treatment options.
