Tree Profiles: Kousa Dogwood, Part 1 (Cornus kousa)

This is the first of a two part series on Kousa dogwood. The following examines the tree’s distribution & habitat, developmental traits, longevity, height, bark, leaves, flowers, and fruit.

Introduction

Kousa dogwood (Cornus kousa), also referred to as Benthamia kousa, Cynoxylon kousa, Chinese dogwood, Kousa, Korean dogwood, and Japanese dogwood is a small, deciduous tree or multi-stemmed shrub in the family Cornacea. Kousa dogwood was first observed in the United States in 1875. It has since become a popular ornamental plant. It is renown for the profusion of star-like blooms it produces in spring, and for its dense, branching canopy when mature. It also displays lush purple to red fall foliage. Kousa dogwood is resistant to many insects and diseases that afflict other dogwoods.

Distribution & Habitat

Kousa dogwood is indigenous to East Asia. It is widespread across China, Japan, and Korea. It has since become established in Europe and North America.

Developmental Traits

Kousa dogwood develops at a slow to medium rate. It increases in height by 1 to 2 feet per year. Young plants are vase-shaped, with a spreading, upright branching habit. When mature, Kousa dogwood assumes a rounder shape, and becomes denser and more horizontal. Kousa dogwood is a hardy plant. It can thrive in full sun and partial shade. It is also moderately tolerant of drought conditions.  Kousa dogwood blooms a month later than flowering dogwood.

Longevity

The life expectancy of Kousa dogwood is between 50 and 150 years.

Height

Kousa dogwood generally reaches heights of 15 to 25 feet, with a 20 to 25 foot spread. Mature trees are often wider than they are tall.

Bark

Kousa dogwood has mottled bark that is slightly exfoliating. The bark ranges from brown to gray or tan in coloration.

Leaves

Kousa dogwood has simple, opposite leaves that are elliptical to ovate in shape. Each leaf is 2 to 4 inches long, and ¾ of an inch to 1 inch in width. When the leaves initially expand, they are bright green. By summer, they turn a dark medium green. In fall, they deepen to a resplendent red or purple. This fall color persists for several weeks, before the leaves are cast.

Flowers

The flowers produced by Kousa dogwood are small, and colored greenish-yellow. The flowers are surrounded by four large, pointed bracts. The bracts are white at first, but turn pink as they age. Kousa dogwood blooms from late May to early June. The bracts can retain their display for up to six weeks. The individual bracts are 1 to 2 inches long, and ½ inch to ¾ of an inch wide. The flowers grow in an upright fashion, along the stems.

Fruit

The fruit is pendant-shaped when young. Once the fruit are mature, they resemble small raspberries. When they first form, the fruit are green. They turn a pinkish-red as they mature. The fruit ripens from late August to October. It is edible, with a distinctly sweet flavor.

 Photo courtesy of Msact at English Wikipedia CC-by-3.0