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Objective 1: Identify Exotic Species

A list of known exotic species was compiled for Rocky Mountain National Park. A complete list, along with synonyms and common names, can be found in Appendix I. Nomenclature follows McGregor et al. (1991).

Objective 2: Rank Exotic Plant Species of RMNP

All known exotic plants of RMNP were evaluated to assess their potential ecological impact. The results for the initial Screening Assessment are displayed in Table 2. Table 2 contains information on the species origin, current distribution, potential distribution, and potential ecological impact. Species were given a score of 1-3 for origin ( 1=not native to North America, 2=native to North America, but not native to RMNP, 3=native to North America, not known to be native to RMNP). Scores from 1-4 were given to species based on the current known distributions ( 1=few, scattered populations; 2=intermediate number of patchy distributed populations; 3=several widespread, dense populations).

In addition, species were ranked according to their potential distribution and potential ecological impact using the Screening Assessment section of the Ranking System for RMNP. Potential distribution (out of a total of 15) and potential ecological impact (out of a total of 40) was assigned to each species. Species which had a total potential ecological impact greater than 24 were identified as species of concern (marked with "*" in Table 2).

The results of the Final Assessment for species of concern are illustrated in Table 3. Table 3 contains additional information on the current level of ecological impact for each species (out of a total of 50), and the relative ease of control (out a total of 100). Species were also assigned 'urgency scores' ranging from 'high' (delay in action will result in significant effort required for control) to medium' (delay in action will result in moderate increase in effort required for control) to 'low' (delay in action will result in little increase in effort required for successful control).