I have a friend who lost a cherished front-yard tree. After the tree surgeons removed the remains, he began the hunt for a new one. The choices were endless. His lot is large and could accommodate a sizeable specimen. The old tree was deciduous, rather than evergreen; as a fan of autumn color, he wanted the replacement to be deciduous as well. After paging through books and catalogs and walking around his neighborhood in search of arboreal magnificence, he fixated on the katsura, or Cercidiphyllum japonicum, a tree that was uncommon in his area. That was fifteen years ago. He still hasn’t picked a tree, but his efforts piqued my interest in the noble and ancient species.
You may have seen a katsura and mistaken it for a North American redbud. The rounded leaves are close in appearance to the round or heart-shaped leaves of redbuds, a fact that gave rise to katsura’s Latin name. “Cercis” is the botanical name for the redbud genus. “Cercidiphyllyum” means, literally, “leaves like redbud.” The two trees inhabit identical USDA hardiness ranges and feature rounded crowns, but the resemblance pretty much stops there. Katsuras are larger trees, topping out at between 40 to 60 feet, with a 25 to 50 foot spread. The smaller North American redbud grows only 20 to 30 feet tall, with a 25 to 35 foot spread. Both produce flowers before leafing out in the spring, but katsura flowers—male and female—are spidery looking, with the female flowers resembling slightly skinnier spiders. Redbud flowers, by contrast, are small, pea-like blooms that clothe the naked spring branches in shades of purplish pink. You won’t see pollinators on a katsura. The wind takes care of the job. Redbuds, on the other hand, are pollinated by hungry bees.
While redbud’s glory is the flowers, katsura’s are renowned for magnificent leaves, which emerge in the spring in a shade of red-purple. Over the course of spring and early summer, they gradually change to blue-green. When early fall rolls around, the foliage metamorphoses into shades of red, apricot and yellow. Even if you can’t see a katsura tree in the fall, you will be able to smell the leaves, which give off an intoxicating burnt-sugar or cotton candy fragrance. This is an attractive trait, especially when you compare the foliage scent to that of the more popular gingko, whose fallen leaves ripen into stinky mush.
As the species name, “japonicum” suggests, katsura is native to Japan, as well as China. The species was first described by Philipp Franz von Siebold, a nineteenth century physician and scientist. Siebold traveled to Japan, made studies of Japanese plants and animals and was co-author of a groundbreaking comprehensive work, Flora Japonica, along with his frequent collaborator, German botanist Joseph Gerhard Zuccarini.
Katsura arrived in the United States in due course and is included in the collections of many arboreta. However, it does not seem to have caught on like the redbud or gingko. Horticultural fashion is sometimes truly mystifying.
Now katsura may be ready for its moment in the sun—literally and figuratively. Years ago Dan Hinkley, then of Heronswood Nursery in Washington State, bred a more compact version, ‘Heronswood Globe,’ with all the desirable traits of the species, but a manageable size of 15 to 20 feet tall. Hinkley mentioned it in a magazine piece not long ago. Dutch breeders have also come up with two standard-size varieties, ‘Raspberry’ and ‘Strawberry,’ noted for fall color that is more deep red than yellow. Not to be outdone, the Germans bred their own standard katsura, ‘Rotfuchs,’ sold here as Red Fox. This tree features new growth that is more red than purple and has the same sweet autumn smell as all the other katsuras.
Lovers of weeping tree forms may be interested in ‘Pendulum,’ a weeping katsura that grows only 15 to 25 feet tall, with fragrant yellow fall foliage.
If you decide to invest in a katsura, know that it is a sun-loving, but thirsty plant with a shallow root system. Katsuras are in hog heaven when planted in spots that feature moisture-retentive clay soil or are relatively damp. If your property is not home to such a site, use drip irrigation to provide plenty of supplemental water, especially when the tree is young. Mulch by applying a 3-inch layer of organic material in a doughnut shape that covers the 2 by 2 foot area around the trunk. Don’t allow the mulch to touch the bark, as that promotes rot and disease.
My friend will someday find a tree and I hope it will be a katsura. He will certainly be the first in his neighborhood to have one. If you want to start a similar trend in your neighborhood, find a young katsura at ForestFarm, 990 Tetherow Road, Williams, OR 97544, (541) 846-7269, http://www.forestfarm.com. Free catalog.