Australia, New Guinea and New Caledonia
also known as paperbark tree, punk tree, cajeput tree, and white bottlebrush
tree, is a subtropical tree in the eucalyptus family, with spongy, white,
paper-like bark that can grow to 50 feet in height. The 1-2 inch long,
gray-green, oval leaves of paperbark tree are arranged alternately along
the stem and smell of camphor when crushed. Flowers are white, brush-like
spikes and the fruits are small, woody, button-like seed capsules.
tree is an aggressive invader that spreads rapidly, converting native plant
communities such as sawgrass marshes, wet prairies, and aquatic sloughs
into impenetrable paperbark thickets. In a single year, one paperbark tree
can produce a dense island hammock nearly 600 feet in diameter. Its greatest
threat is to the Florida Everglades ecosystem, which faces extreme and
possibly irreversible alteration as a result of intrusion by paperbark
tree and another troublesome exotic, Brazilian pepper (Schinus terebinthifolius).
IN THE UNITED STATES
The distribution of paperbark tree in the U.S.
is currently confined to southern Florida, where it occupies an estimated
several million acres, primarily within the Florida Everglades system.
HABITAT IN THE UNITED
Paperbark tree tolerates most subtropical ecosystems, preferring
wet to intermittently wet sites.
Introduced into southern
Florida in the early 1900s, paperbark tree was widely planted for landscaping
and for "swamp drying."
BIOLOGY & SPREAD
three years after germination, paperbark trees begin to produce and store
copius numbers of seeds in closed woody capsules. The seeds are stored
until some form of stress, such as frost, fire or human- induced injury,
including herbicide, causes the capsules to open. A mature tree can produce
more than a million seeds per year and store an estimated 20 million. Seeds
of paperbark tree are dispersed by wind and water.
of areas infested with paperbark tree requires a well planned, long term
commitment to elimination of all paperbark trees from the site and prevention
of reinfestation. The age and extent of an infestation, the availability
of people and other resources, and the proximity to open water or wetlands
will dictate the type of management best suited for each site. Seedlings
can be pulled by hand, especially when the soil has dried out some, small
to medium-sized trees can be pushed over, and larger trees may be cut.
Resprouting will likely occur after cutting or hand- pulling, requiring
follow-up removals or treatment with herbicide.
Herbicides are usually
needed for extensive infestations and mature paperbark trees and may be
applied to freshly cut stumps or to girdled trunks. However, as noted previously,
herbicide use will cause paperbark tree to release large caches of stored
Biological control may
offer some help in management of this aggressive invader. Several species
of Australian snout beetles are being released or evaluated by the U.S.
Department of Agriculture. The beetles are specific to Melaleuca and feed
on its shoots, reducing the plant's ability to reproduce.
USE PESTICIDES WISELY: ALWAYS READ THE ENTIRE PESTICIDE LABEL CAREFULLY, FOLLOW ALL MIXING AND APPLICATION INSTRUCTIONS AND WEAR ALL RECOMMENDED PERSONAL PROTECTIVE GEAR AND CLOTHING. CONTACT YOUR STATE DEPARTMENT OF AGRICULTURE FOR ANY ADDITIONAL PESTICIDE USE REQUIREMENTS, RESTRICTIONS OR RECOMMENDATIONS.
NOTICE: MENTION OF PESTICIDE PRODUCTS ON THIS WEB SITE DOES NOT CONSTITUTE ENDORSEMENT OF ANY MATERIAL.
For more information
on the management of melaleuca, please contact:
- Francois Laroche, francois.laroche at sfwmd.gov
Jil M. Swearingen, National Park Service, Washington, DC
Barry A. Rice, The Nature Conservancy,
Florida Exotic Pest Plant Council.
1991. Exotic Woody Plant Control, Ken Langeland, ed.
Mazzotti, F.J., T.D. Center, F.A.
Dray, and D. Thayer. Ecological Consequences of Invasion by Melaleuca
quinquenervia in South Florida Wetlands: Paradise Damaged, not Lost. http://edis.ifas.ufl.edu/UW123
Randall, J.M. and J. Marinelli.
1996. Invasive Plants: Weeds of the Global Garden. Brooklyn Botanic Garden
Club, Inc., Handbook No. 149. Pp. 36
Schultz, D.P., T.W. Barnes,
and J.M. Kleen. 1987. Melaleuca control at Loxahatchee National Wildlife
Refuge. U.S. Fish and Wildlife Service, Atlanta, GA and Boynton Beach,
Swearingen, J. 2009. WeedUS Database of Plants Invading Natural Areas in the United States: Melaleuca (Melaleuca quinquenervia). http://www.invasive.org/weedus/subject.html?sub=2783.
USDA, NRCS. 2009. The PLANTS Database (http://plants.usda.gov). National Plant Data Center, Baton Rouge, LA 70874-4490 USA.
Plant Conservation Alliance, Alien Plant Working Group.