In order to examine the accuracy of the energy analysis method, economic
techniques were also used to compute the cost of providing several kinds
of services with technology. The results, in close agreement, indicate that
Capitol Park has a capital asset value between 400',000 and 2 million dollars
and provides annually services worth $14,000 to-$70,000. While the evaluation
methodology may be improved and expanded, the method is relatively easy to apply
and the results provide some indication of the value of our trees and vegetation
in urban settings.

 The energy analysis calculations are based on the energy requirements
of producing or sustaining the trees or ecosystem. Yet this leads to another
measurement problem. The value of trees is, then a function not only of
the embodied energy or money in the substituted technology, but it is also a
function of the value society places on the end use services. That is, we need
to factor in the value society has for a particular end use and adjust the
thermodynamic and/or economic estimates accordingly. Of particular concern
would be society's demand (or need) for the services, whereas the energy
calculation focuses more on the supply aspects of the services. Economists
might argue that the price of providing the alternate technology is a reflec-
tion of the value society places on the services, yet the area of environmental
quality, quality of life, and economics is not that precise as yet. Many
pollution control functions are subsidized through government loans, regulatory
programs and the like, thereby warping the economic reflections of the value
of pollution control. Additionally, the societal value may change from
environment to environment, season to season, with changing levels of education
in the populus, and in differing economic climates.

 We would propose a general evaluation model for societal end use value of
natural systems functions which might also be a quantification of appropriateness;
which would include the following components.

 1. The energetic of the system (since we do not pay nature for her
 services), where:

 EQI = Energy Quality Units of Input
 (to run the natural system)

 2. The end use economic and energetic value of the services provided
 and the societal value of those end used, where:

 EU = End Use (energy cost of replacement technology
 by human application)

 Then for each technology where there is a substitute function by natural
systems or renewable, natural based energies, the value of the natural system
functions (NSV) would be calculated by:

 E = Natural Systems Value = NSV =
 A Measure of Appropriateness

 Once established, a sliding scale of NSV's could be used to compare the
various "appropriate technologies" with each other and with the high technology
options they could replace. Yet for now, an NSV of less than 1 would signify