-22- 



The higher the final total for each area the greater the variety 

 of natural features and the more desirable the area. This system puts 

 a premium on diversity. To be sure that areas of low diversity but of 

 critical importance — a bog for example — were included in the final 

 recommendations, the entire list was reviewed after numerical analysis 

 and some areas were added to the list on the basis of ecological judgement. 



To correct in part for the bias caused by unequal availability of 

 evaluation data, Maryland and Virginia areas were evaluated separately. 

 This was a necessary precaution, considering the much greater availability 

 of information on sites in Maryland, in relation to that for Virginia. 

 When the wetland survey, which the Virginia legislature has charged the 

 Virginia Institute of Marine Sciences to undertake is complete, this 

 imbalance may be easily redressed. 



Due to financial and time limitations it was impossible to visit 

 all of the areas under initial consideration. Preliminary sorting of 

 available data should isolate the best areas which could then be visited 

 for in-depth study, analysis, selection, and ranking. The extrinsic 

 factor, especially, might be best evaluated in the field. 



A weighting system is desired which gives greater importance to 

 plant communities or types not in the National System of Natural Areas, 

 than for those for which there are many examples. Also, the factors 

 of diversity, quality, lack of past and present disturbance, protectability 

 and other factors must be considered with appropriate weighting. The 

 factors of esthetic and emotional value should receive a rating based on 

 subjective instead of scientific grounds. An example would be the 

 comparison of the importance of saving the condor or eagle in comparison 



