Cover Photos

Top center: Yellow star thistle (J. Asher, Bureau of Land Management, DOI).
Left center: Asian longhorned beetle (Animal and Plant Inspection Service, USDA).
Right center: Orange infested with citrus canker (Animal and Plant Inspection Service, USDA).
Bottom left: Chinese mitten crab (Lee Mecum, California Department of Fish and Game).
Bottom right: brown tree snake (T. Fritts, U.S.Geological Survey, DOI).

A brief description of each photo follows:

Yellow star thistle—Centaurea solstitialis, was introduced from southern Europe and the Mediterranean region in the mid-1800s. It has become a serious weed pest throughout the western United States (U.S.). This thistle now infests more than 10 million acres of rangeland in the western U.S. where it has greatly reduced forage production for livestock and disrupted natural ecosystems.

Asian longhorned beetle—Anoplophora glabripennis, is native to China where it is a serious pest of hardwood trees and has been introduced in to the U.S. in infested wood in packing crates. If this insect becomes established in the environment, it could destroy millions of acres of treasured hardwoods.

Citrus canker—is a plant disease caused by the bacterium, Xanthomonous axonopodius pathovar citri, which infests fruit, twigs, and stems. The disease was first reported in the U.S. in 1910 and, although contained by an aggressive prevention and management program, has reoccurred periodically. Only a continued state and federal program consisting of surveys to detect infested trees, removal and destruction of infected and adjacent trees, and prevention through regulatory actions have prevented citrus canker from devastating the U.S. citrus industry.

Chinese mitten crab—Eriocheir sinensis, was initially reported in the San Francisco Bay in 1992 and its populations have expanded rapidly and are adversely affecting fish populations in selected areas. In addition, its burrowing activities are undermining stream banks and levees, leading to increased erosion and flooding, and disruption of agricultural irrigation systems.

Brown tree snake—Boiga irregularis, has become a serious pest in Guam where it has virtually eliminated the native forest birds. The snakes feed on a wide variety of animals including lizards, birds, and small mammals as well as bird and reptile eggs. Snakes frequently invade poultry houses, homes, and yards to consume domestic poultry, eggs, pet birds, and small mammals. The species is mildly venomous and a possible health risk, especially to small children. Several specimens have been intercepted in cargo arriving in other parts of the U.S. from Guam. The establishment of the snake elsewhere in the U.S. could have very adverse consequences.



Cover design by

Fleishman-Hillard, Inc.
Kansas City, Missouri