INVASIVE EXOTIC PLANT MANAGEMENT PLAN and ENVIRONMENTAL ASSESSMENT Rocky Mountain National Park Yellow Toadflax in Horseshoe Park Prepared by: U.S. Department of the Interior National Park Service Rocky Mountain National Park Colorado August, 2003 Invasive Exotic Plant Management Plan and Environmental Assessment Rocky Mountain National Park August, 2003 Abstract: National Parks represent complex communities of native plants and animals. The ecological balance within these communities is currently threatened by the invasion of exotic plants. Controlling invasive exotic plants is a serious challenge facing National Park Service (NPS) managers, who are charged with the protection of natural and cultural resources. Over one hundred species of exotic plants occur in Rocky Mountain National Park (RMNP). Of these, 35 species are of particular concern because they are aggressive and invasive and have the potential to displace native vegetation. RMNP proposes a proactive approach to manage exotic plant infestations, including mechanical, cultural, chemical, and biological control techniques. Of the 35 invasive exotic species identified for control, herbicides will likely be used on only 15 of those species. Citizens and environmental organizations have expressed concern over chemical control (use of synthetic herbicides), which prompted the Park to develop a new Invasive Exotic Plant Management Plan and Environmental Assessment (EA) to replace the Plan and EA released for public review in February 2000. This Plan and EA addresses those concerns and examines alternatives for controlling invasive exotic herbaceous plants and grasses, including lower risk techniques such as scalding exotic plants with hot water (steam), and using biodegradable natural chemicals that are acceptable herbicides used by organic farmers. If synthetic herbicides are used, the park would use the least toxic effective herbicide only after making a good faith effort to control invasive exotics using other control techniques. List of Abbreviations ATV All Terrain Vehicle BLM Bureau of Land Management CDOT Colorado Department of Transportation CDOW Colorado Division of Wildlife CE Categorical Exclusion CNAP Colorado Natural Areas Program CNHP Colorado Natural Heritage Program DBG Denver Botanical Gardens DWLOC Drinking Water Level of Comparison EA Environmental Assessment ESA Endangered Species Act FWS U.S. Fish and Wildlife Service HTP Human Toxicity Potential IEMP Invasive Exotic Management Plan IPM Integrated Pest Management i MCS Multiple Chemical Sensitive MSDS Material Safety Data Sheet NEPA National Environmental Policy Act NPS National Park Service NRCS Natural Resources Conservation Service, U.S. Department of Agriculture PPE Personal Protective Equipment RMNP Rocky Mountain National Park USDA United States Department of Agriculture USFS United States Forest Service Definitions Several terms are defined to facilitate understanding of this Plan and EA: Native Plant – The NPS defines native plants as all species that have occurred or now occur as a result of natural processes on lands designated as units of the national park system. Native species in a place are evolving in concert with each other (NPS 2001). A goal of the NPS is to perpetuate native plants and animals as part of the natural ecosystem. Exotic Plant – The NPS defines exotic species as those species that occupy or could occupy park lands directly or indirectly as the result of deliberate or accidental human activities. Because an exotic species did not evolve in concert with the species native to the place, the exotic species is not a natural component of the natural ecosystem at that place (NPS 2001) Invasive Exotic Plant - An aggressive plant that is known to displace native plant species. Invasive exotic species are unwanted plants which are harmful or destructive to man or other organisms (Holmes, 1979; Webster). State Listed Noxious Weeds – Invasive exotic plants prohibited or restricted by Colorado Law. Many of the invasive exotic plants known to occur in RMNP fall into this category (please refer to Table 1 on page 3). Transporting seed or parts of these plants, or allowing them to seed on one’s property is prohibited. RMNP does propose to control a few invasive exotic plants that are not State Listed Noxious Weeds because they pose a threat to the park’s natural resources. Integrated Pest Management (IPM) - A decision-making process that coordinates knowledge of pest biology, the environment, and available technology to prevent unacceptable levels of pest damage, by cost-effective means, while posing the least possible risk to people, resources, and the environment (NPS, 2001). Proposed Integrated Pest Management Control Techniques: Mechanical: Using tools to remove plants by mowing, digging, and cutting seed heads and plants. Cultural: Providing competition, stress, or control of exotic species by planting native vegetation or burning exotic plants. Chemical: Using synthetic herbicides to kill or severely stress invasive exotic plants. ii Biological: Using insects, mammals or pathogens to stress exotic plants. Low Risk Methods: Using hot water (steam) to scald exotic plants, or using natural chemicals that may contain biodegradable soap, acetic acid, sugar compounds, or plant proteins. iii INVASIVE EXOTIC PLANT MANAGEMENT PLAN And ENVIRONMENTAL ASSESSMENT Rocky Mountain National Park, Colorado Summary The National Park Service (NPS) is examining ways to manage and control exotic plant infestations in Rocky Mountain National Park (RMNP). Thirty-five species of invasive, exotic herbaceous plants and grasses are of concern to park managers (please refer to Table 1 on page 3). These invasive species, occurring on an estimated 427 acres of park land, displace natural vegetation and consequently affect the long-term health of native plant and animal communities. Of the 427 infested acres, 65.25 acres would be managed using the full range of IPM techniques, including the use of synthetic herbicides. RMNP released an Invasive Exotic Plant Management Plan (Plan) and Environmental Assessment (EA) for public review in February 2000. The Plan proposed using IPM techniques, including mechanical, cultural, synthetic herbicides, and biological controls to eradicate or reduce exotic plant species. It did not include using low risk methods such as hot water and natural chemicals that are acceptable herbicides used by organic farmers. Thirty-eight responses from citizens and environmental organizations were received. Concerns expressed by respondents focused on the use of synthetic herbicides and their potential effects on the environment and people. Additionally, some respondents wanted to be properly notified if, when, and where herbicides were to be used. To address these concerns RMNP has prepared this new Plan and EA. No synthetic herbicides have been used in the park for the last two years, and will not be used until a Plan has been approved. This new plan and EA examines in detail two alternatives: the continuation of current management practices and the preferred alternative. The no action alternative was also evaluated but rejected from further consideration. The preferred alternative will have no adverse impact on geology and topography; threatened, endangered, candidate species or species of special concern; natural lightscapes; archeological resources, cultural landscapes, historic structures, and museum collections; prime and unique farmlands; ethnographic resources; socioeconomics of the park and nearby communities; or environmental justice. There would be short-term negligible to minor adverse impacts to soils and native vegetation; aquatic, wetland and riparian communities; natural soundscapes; wildlife; recommended wilderness; air quality; human health and safety; park operations; and visitor use. Weed management activities will be an inconvenience and will intrude on some visitor’s park experience. These impacts will be adverse, short- term, localized and minor. There would be long-term beneficial effects to soils and native vegetation; threatened, endangered, candidate species or rare species; aquatic, wetland and riparian communities; park operations; and visitor use. iv RMNP proposes a proactive approach to managing invasive exotic plants. If left unchecked, invasive exotic plants could spread to unmanageable levels and cause long- term harm to the park’s natural and cultural resources. This Plan provides the blueprint for managing exotic plants, while fulfilling the NPS mandate of protecting and preserving natural resources and the human environment. The Plan’s primary objectives are to eradicate, significantly reduce, or contain populations of thirty-five species of invasive exotic plants in the park, and to aggressively eradicate any new invasive exotics that may invade the park in the future. To accomplish this, the Plan calls for the following actions: Proposed Actions • Action 1 - Inventory and monitor invasive exotic plants in RMNP. • Action 2 - Prioritize exotic plants to be controlled. • Action 3 - Identify control techniques most appropriate for each species. • Action 4 - Apply the most appropriate control technique for each species. • Action 5 - Monitor effectiveness of control efforts. • Action 6 - Prevent new infestations by monitoring invasive exotic plant pathways. • Action 7 - Inform the public about RMNP exotic plants and control methods. • Action 8 - Work with adjacent landowners and local, county, state and federal agencies. The eradication or control of