The development of successful regional or national invasive weed control programs is often hampered by the way the problem is approached. Typically weed control programs are developed and evaluated solely from the perspective of the biological sciences. While this is appropriate from a local or landscape perspective, it will probably not produce the desired results when addressing widespread well-established infestations that impact large regions. The "Ecological Area-wide Management (TEAM) of Leafy Spurge" program was the first U.S. Department of Agriculture (USDA), Agricultural Research Service (ARS) area wide invasive weed program. The 5-year program, funded by the ARS and conducted cooperatively with the USDA Animal and Plant Health Inspection Service, focused on the control of leafy spurge (Euphorbia esula L.) in North Dakota and South Dakota, Montana and Wyoming. Now in its final year (2001), the TEAM Leafy Spurge program has made significant progress in controlling leafy spurge, increasing public awareness of the problem and demonstrating the effectiveness of biologically-based integrated pest management. While this is a significant accomplishment, the lessons learned over the course of the project clearly demonstrate that the success of regional weed control programs depends on more than a persistent, marked reduction in the pest population. Effective regional weed control programs need to focus not only on biological issues, but also on the ecological, scientific, economic, social and legal factors that influence the effectiveness of the program. Therefore, the implementation and subsequent evaluation of a weed control program must include all the principal factors that will ultimately determine success and sustainability. This manuscript outlines the history of leafy spurge on the North American continent, the situation currently facing weed managers, and an evaluation of the TEAM Leafy Spurge program's success for each factor listed above. The final analysis indicates that successful biologically-based leafy spurge control is on the horizon, especially when weed managers understand the number of problem areas that must be addressed to achieve a sustained reduction of a weed population. The amount of time it will take to be realized depends on our commitment to solving the problem and our willingness to work together as a cohesive team.

A 3-year experiment to evaluate tracked vehicle effects on vegetation and soil characteristics was established on the Gilbert C. Grafton South State Military Reservation (CGS) in North Dakota. Study objectives were to evaluate the effects of 3 tracked vehicle use intensity treatments on plant species cover and frequency, and soil compaction. The 3 treatments evaluated include heavy use (74 passes), moderate use (37 passes) and no use. The moderate use treatment represents a typical use of 1 battalion unit at CGS with the heavy use treatment classified as 2 battalion units. This land area comprised a 50 by 150 meter block subdivided into three, 50 by 50 meter blocks. Each 50 by 50 meter block was subdivided into three, 16.7 by 50 meter blocks with each block treated with 1 of the 3 treatments. Soil bulk density increased (P < 0.05) on the moderate and heavy use treatments in the 0 to 15, 30 to 45, and 45 to 60 cm soil depths. Kentucky bluegrass (Poa pratensis L.) cover (P < 0.05) decreased in 1996 on both the moderate and heavy use treatments but was not (P > 0.05) different among all treatments in 1997. The tracked vehicle use on the heavy and moderate treatments did not change species composition or litter amounts after 2 years; however, bulk density and bare ground increased on both treatments in 1996 and 1997.

Prescribed burning in Theodore Roosevelt National Park has played an important role in maintaining a natural ecosystem. However, changes in plant community dynamics caused by burning may have led to an invasion of weedy species such as Canada thistle (Cirsium arvense L.). The objectives of this research were to evaluate the effect of a fall burn before spring herbicide application on Canada thistle control and to evaluate the soil seedbank within Canada thistle infestations. Canada thistle stem densities initially were higher in the burned compared with the nonburned areas because plants were slower to emerge in the nonburned treatments. However, the effect was short-lived, and Canada thistle densities were similar in the burned and nonburned treatments by the second season following the prescribed burn. Canada thistle control averaged 78% 60 days after treatment with clopyralid, clopyralid plus triclopyr, or picloram when spring applied whether or not application was preceded by a prescribed burn. Control declined to less than 60% by 363 days after application. Grass cover increased from an average of 5% before treatment to 37% and 46% 60 and 425 days after herbicide application, respectively, regardless of burn treatment. Forb cover increased following a prescribed burn but was unaffected by herbicide treatment. Overall the number and variety of species in the soil seedbank was not affected by a prescribed burn. A total of 74 species (56 forbs, 13 grasses, and 5 other mesic species) were found in the soil seedbank. However, the majority of the soil seedbank consisted of nondesirable low seral and invasive species including Canada thistle and Kentucky bluegrass (Poa pratensis L.), which accounted for over 80% of the total germinated seed. Although a prescribed burn caused an initial increase in Canada thistle density and cover, the greater long-term concern may be the lack of desirable species present in the seedbank to replace Canada thistle once the weed is controlled. Resumen La quema prescrita en el Parque Nacional Theodore Roosevelt ha jugado un papel importante en mantener un ecosistema natural. Sin embargo, cambios en las diná micas de la comunidad vegetal causadas por las quemas puede conducir a una invasió n de malezas, tal como el ''Canada thistle'' (Cirsium arvense L.). Los objetivos de esta investigació n fueron evaluar el efecto de la quema en otoñ o antes de la aplicació n de herbicidas en primavera para del ''Canada thistle'' y evaluar el banco de semillas del suelo en infestaciones del ''Canada thistle.'' Las densidades de tallos del ''Canada thistle'' inicialmente fueron mayores en las áreas quemadas que en las no quemadas porque las plantas fueron lentas en emerger en los tratamientos no quemados. Sin embargo, el efecto fue corto, y para la segunda estació n de crecimiento después de la quema prescrita las densidades de ''Canada thistle'' fueron similares en los tratamientos quemados y no quemados. El control de ''Canada thistle'' promedio 78% 60 días después de aplicar el tratamiento de clopir...

The Ecological Areawide Management (TEAM) of Leafy Spurge program was developed to focus research and control efforts on a single weed, leafy spurge, and demonstrate the effectiveness of a coordinated, biologically based, integrated pest management program (IPM). This was accomplished through partnerships and teamwork that clearly demonstrated the advantages of the biologically based IPM approach. However, the success of regional weed control programs horizontally across several states and provinces also requires a vertical integration of several sectors of society. Awareness and education are the essential elements of vertical integration. Therefore, a substantial effort was made to produce a wide variety of information products specifically designed to educate different segments of society. During its tenure, land managers and agency decision makers have seen the potential of using the TEAM approach to accelerate the regional control of leafy spurge. The example set by the TEAM organization and participants is viewed as a model for future weed-control efforts.