854 Cinnamomum camphoraCommon Names: camphor tree, camphor laurel, shiu leaf, gum camphor, laurel camphor Family: Lauraceae (laurel Family)
The camphor tree is a dense broadleaved evergreen that is capable of growing 50-150 ft (15.2-45.7 m) tall and spreading twice that wide with a trunk up to 15 ft (4.6 m) in diameter, though the largest U.S. specimens are only half that size and those in the Caribbean are even smaller. The shiny foliage is made up of alternate 1-4 in (2.5-10.2 cm) oval leaves dangling from long petioles. Each leaf has three distinct yellowish veins. The outer margins of the leaves tend to be somewhat wavy and turn upward. The new foliage starts out a rusty burgundy color, but the leaves soon turn dark green on the upper sides and paler green underneath.
New branches emerging from the shallowly fissured grayish brown trunk are smooth and green. Twigs are usually green, but may be tinged with red when young. The inconspicuous tiny cream colored flowers are borne in the spring on branching 3 in (7.6 cm) flower stalks. They are followed by large crops of fruit, comprised of round pea sized berries attached to the branchlets by cuplike little green cones. The berries first turn reddish, then ripen to black. Camphor tree can be readily identified by the distinctive odor of a crushed leaf.
Cinnamomum camphora, the camphor tree, comes from China, Japan, Korea, Taiwan, and adjacent parts of East Asia, where it grows in mesic forests and on well-drained sites along streambanks. Camphor has become widely naturalized in Australia. In the United States, it is grown along the Gulf Coast and in California, and has escaped cultivation and become naturalized in many areas.
CultureCamphor prefers fertile sandy soil. It will tolerate a pH anywhere in the range of 4.3 to 8. The roots are very sensitive to disturbance. They may extend far from the trunk of the tree, and can readily be identified by their characteristic odor. Light: Camphor will grow in full sun or partial shade. Moisture: Camphor tree does not do well in wet soils. Established trees are tolerant of drought. Hardiness: USDA Zones 8 - 10. Hardened off camphor trees can survive freezes down to 10-15ºF (-12 - -9ºC), but new growth will suffer freeze burn when the temperature drops below 32ºF (0ºC) and branches will die back from temperatures in the low twenties. Propagation: Camphor seed does not remain viable for long and should be planted in the greenhouse as soon as it ripens. Remove the fruit pulp first. At 68ºF (20ºC), germination will take 1-6 months. Cuttings of semiripe side shoots can be rooted in a warm humid place in midsummer. Pieces 2-3 in (5.1-7.6 cm) long with a heel work best.
Camphor is widely planted as a shade tree, screen, or windbreak. In China and Japan, it is grown commercially for its medicinal oil. Camphor oil has a strong penetrating fragrance, a pungent bitter flavor, and feels cool on the skin like menthol, though it also has irritating qualities as well as a numbing effect. Camphor has been used to treat ailments ranging from parasitic infections to toothaches. Scientific evidence has confirmed that chemicals in the plant have value in antiseptics and medications for treating diarrhea, inflammation, itching, and nervous conditions. Camphor wood is prized for its attractive red and yellow striping, amenability to woodworking, and insect repelling properties. It is light to medium in weight and soft to medium in hardness. Wood from the camphor tree is not especially strong, but it takes polishing well. It is commonly used for chests, closets, coffins, instruments, and sculptures. Camphor veneer is used in fine cabinetry. Camphor is also used in perfumes.
This is a sturdy storm resistant tree which makes a good windbreak. Since it is hard to burn, it should also be valuable as a shade tree in areas that are prone to wildfires. Unfortunately, these desirable traits are offset by the tree's invasiveness and damaging effects on wildlife and natural communities. This fine tree should be grown and appreciated in its native range, but not planted in other regions where species and ecosystems have not adapted to its aggressiveness and toxicity. Camphor tree should not be grown in the United States.
Camphor in large doses is toxic to humans. It stimulates the central nervous system and may affect respiration or cause convulsions. In Chinese medicine, camphor is forbidden for pregnant women and those with a deficiency of vital energy or yin. Camphor is a prolific seed producer that apparently does not have serious predators or diseases outside its native range. Seedlings and root sprouts are abundant near mature trees, but individual trees pop up far from seed sources. In Florida, camphor trees appear in undisturbed mesic hardwood forests, upland pine woods, and scrubs, as well as in the vacant lots and fencerows where it is more commonly observed. The Plant Conservation Alliance lists this species as an Alien Invader and it is listed as a Category I invasive exotic species by the Florida Exotic Pest Plant Council, which means that it is known to be "invading and disrupting native plant communities in Florida."
Linda Conway Duever 10/31/00; updated 6/15/04, 4/22/05