Cornus

Cornus unalaschkensis 8561f

Cornus mas F

Blooming Dogwood

Cornus drummondii1

Bunchberry plants

Cornus is a genus of woody plants in the family Cornaceae, commonly known as dogwoods. They are native throughout the temperate world, including parts of North America, Europe, Asia, and Africa. The genus includes a variety of species, ranging from small shrubs to large trees. Dogwoods are known for their attractive flowers, colorful fruit, and distinctive bark. They play a significant role in horticulture, used in landscaping and garden design for their aesthetic appeal and in some cases for their timber.

Description

Members of the genus Cornus exhibit diverse growth habits, with some species growing as low shrubs while others mature into large trees. The leaves are simple, opposite (in most species), and vary in color from green to purple in the fall, depending on the species. The flowers are typically small and are often arranged in clusters surrounded by large, showy bracts which can be mistaken for petals. The actual petals are small and inconspicuous. The fruit of Cornus species is usually a berry-like drupe, varying in color from red to blue or black, and is often an important food source for wildlife.

Ecology

Dogwoods are found in a variety of habitats, from forest understories to open fields and edges of water bodies. They are adaptable to a range of soil types, though they generally prefer moist, well-drained soils. The flowers provide nectar for pollinators such as bees and butterflies, while the fruit is eaten by birds and mammals, aiding in seed dispersal. Some species of Cornus are used as food plants by the larvae of certain species of butterflies and moths, further integrating these plants into their ecosystems.

Cultivation and Uses

Dogwoods are popular in horticulture for their beautiful flowers, foliage, and sometimes colorful stems. They are used in landscape design as specimen plants, for naturalizing, or in mixed borders. While most dogwoods prefer partial shade, they can adapt to a range of light conditions. They require minimal maintenance once established, but can be susceptible to various pests and diseases, including dogwood anthracnose, caused by the fungus Discula destructiva.

In addition to their ornamental value, some species of Cornus are valued for their hard, dense wood, which is used in tool handles and other small items requiring tough, shock-resistant material. The fruit of some species is also used in traditional medicine and as a source of dye.

Species

There are numerous species within the genus Cornus, including:

• Cornus florida – Flowering dogwood, native to eastern North America
• Cornus mas – Cornelian cherry, native to southern Europe and southwest Asia
• Cornus kousa – Kousa dogwood, native to East Asia
• Cornus sanguinea – Common dogwood, native to Europe and western Asia
• Cornus sericea – Red osier dogwood, native to North America

Conservation

While many species of Cornus are common and not considered at risk, habitat destruction and disease have placed some species in vulnerable positions. Conservation efforts are focused on habitat preservation and the management of diseases such as dogwood anthracnose, which can severely impact populations of susceptible species.