Cornus alba: From Blooms to Branches, All You Need to Know

The Cornus alba is a deciduous shrub from the Cornaceae family, growing up to 3 meters tall. Its bark is purplish-red, young twigs are covered with pale white short soft hairs, which gradually shed and are replaced by a waxy white powder.

The older branches are red and white, dotted with gray-white round lenticels and slightly protruding annular leaf scars. Its leaves are opposite, elliptical, and the inflorescence is terminal.

The flowers are milky white and bloom from May to June. The fruits are milky white or blue-white and mature from August to October. Propagation can be done through seeding, cuttings, and layering.

The Red-barked dogwood features bright red autumn leaves, clean white small fruits, and its branches turn a brilliant red like coral after the leaves fall, making it a rare stem-viewing plant and an excellent source of cut branches.

It is often planted in clusters on lawns or interspersed with evergreen trees in gardens, creating a beautiful contrast of red and green.

I. Morphological Features

This shrub grows up to 3 meters tall, with purplish-red bark. Young branches have pale white short soft hairs, which eventually fall off and are covered with a waxy white powder.

Old branches are red and white, with scattered gray-white round lenticels and slightly raised annular leaf scars. Winter buds are ovate-lanceolate, 3-6 mm long, and covered with gray-white or light brown short soft hairs.

Leaves are opposite, paper-like, and elliptical or rarely ovate, 5-8.5 cm long, 1.8-5.5 cm wide, with pointed tips and wedge-shaped or broad wedge-shaped bases.

The edges are entire or slightly curled, the upper surface is dark green with very few white flat short soft hairs, and the underside is powder-green, covered with white appressed short soft hairs.

Sometimes the vein axils have light brown beards, the midrib is slightly recessed on the upper side and protrudes on the underside, the lateral veins (4-)5(-6) pairs are arch-shaped and inward-curving, appearing slightly on both sides.

The inflorescence is a denser, 3 cm wide, terminal umbel covered with white short soft hairs. The total flower stalk is cylindrical, 1.1-2.2 cm long, covered with pale white short soft hairs.

Flowers are small, white or pale yellow-white, 5-6 mm long, 6-8.2 mm in diameter. The petals are 4, ovate-elliptical, 3-3.8 mm long, 1.1-1.8 mm wide, with acute or short acuminate tips, hairless on the upper side, and sparsely covered with appressed short soft hairs on the underside.

The stamens are 4, 5-5.5 mm long, attached to the outside of the flower disc. The pistil is cylindrical, 2.1-2.5 mm long, almost hairless.

The ovary is inferior, and the fruiting pedicel is slender, 2-6.5 mm long, covered with light white short soft hairs, and has a joint at the junction with the ovary.

The drupe is long-oval, slightly flat, about 8 mm long, 5.5-6 mm in diameter, milky white or blue-white when ripe, with a persistent pistil. The nutlet is edge-shaped, side-flattened, slightly pointed at both ends, 5 mm long, 3 mm wide, with 3 veins on each side.

The fruiting pedicel is slender and cylindrical, 3-6 mm long, with sparsely growing short soft hairs. Flowers bloom from June to July, and fruits mature from August to October.

II. Growth Environment

These plants thrive in mixed forests or mixed coniferous and broad-leaved forests at altitudes of 600-1700 meters (up to 2700 meters in Gansu province).

Redwood trees prefer a warm and humid environment and thrive at temperatures of 22-30 degrees Celsius with abundant sunlight. They grow rapidly in well-drained, nutrient-rich conditions, and enjoy a fertile environment.

Attention should be paid to drainage in the summer, while in some northern regions, they may be prone to frost damage in winter.

III. Distribution Range

They are found in North Korea, the Soviet Union, and other parts of Europe.

IV. Growth and Reproduction

Propagation can be achieved through sowing, cutting, or layering. For sowing, seeds should be sown in spring after sand storage.

Cuttings can be taken from one-year-old branches, stored in sand during autumn and winter, and planted from March to April of the following year.

Layering can be done in May by girdling a branch and burying it in the soil, then separating it from the parent plant for transplantation in the following spring.

V. Pest and Disease Control

To prevent leaf spot disease, plants should not be planted too densely, and pruning should be carried out to facilitate ventilation and light penetration. Watering should ideally be done in the morning on sunny days without wetting the leaves.

Spraying with a 1000-fold dilution of 70% methyl tobujin wettable powder, or a 250-300-fold dilution of 25% carbendazim wettable powder, or a 700-800-fold dilution of 75% chlorothalonil wettable powder can be used as preventive measures.

Spray once every 10 days. If the disease is severe, spray with a 600-800-fold dilution of 65% zinc dimethyldithiocarbamate, or a 1000-fold dilution of 50% carbendazim to control the spread and expansion of the disease.

To control powdery mildew, spray with a 200-fold dilution of Bordeaux mixture or an 800-fold dilution of chlorothalonil. Once this disease occurs, in addition to removing the diseased leaves, a spray of 0.3-0.5-degree lime sulfur mixture is also required.

To control aphids, spray with a 2000-fold dilution of 50% imidacloprid wettable powder, or a 1500-fold dilution of 20% imidacloprid emulsion, or a 1000-1500-fold dilution of 50% imidacloprid emulsion, or a 2000-fold dilution of 50% chlorpyrifos emulsion, or a 1000-fold dilution of 80% dimethoate emulsion.

To prevent stem rot, spray with a 4 to 5-degree sulfur mixture in March when buds sprout, and spray with a 1:1:200 Bordeaux mixture before the rainy season.

VI. Primary Value

Gardening Value

This plant is often grown in groups on lawns or interspersed with evergreen trees in gardens, creating a contrast of red and green.

Its branches remain red all year round, making it an unusual choice for landscape design. Its seeds contain about 30% oil, which can be used industrially, and it is commonly cultivated as an ornamental plant for gardens.

Landscape Purpose: It is used for garden viewing and group planting. The red tip tree has bright red autumn leaves and clean white small fruits. After the leaves fall, the branches are as red and bright as coral.

It is one of the rare plants that are appreciated for their stalks and it is also a good material for cut branches. It is often grown in groups on lawns or interspersed with evergreen trees in gardens, resulting in a red and green contrast effect.

Medicinal Value

Functions and Indications

It is used for clearing heat and detoxifying, stopping diarrhea, and stopping bleeding. It is mainly used for diarrhea caused by damp heat, nephritis, rheumatic joint pain, red and swollen eyes, otitis media, hemoptysis, and blood in stools.

Taste and Nature

The taste is bitter and slightly astringent, and it is cold in nature.

Usage and Dosage

For internal use: decoction, 6-9g. For external use: appropriate amount, decoction for washing, or ground into powder for sprinkling.

Harvesting and Storage

They can be harvested all year round and need to be cut into sections and dried in the sun.