If, on the other hand, the analyst errs in com- 
bining detail which the manager needs, the in- 
formation is lost, and field or interpretive work 
must be repeated to retrieve the buried infor- 
mation. 
Effective use of a more detailed resource 
analysis does require a higher level of ecologi- 
cal understanding by the user. Often the confu- 
sion of a good map and legend merely results 
from contrast with the gross generalizations 
and inadequate resource maps the manager 
has used. The resource analyst who paints 
a picture of the resource as it is, with sound 
ecological interpretations, is providing for both 
today and tomorrow. His efforts should provide 
more adequate information under the growing 
concept of “acre management” than do the 
older surveys. The former are forward-looking 
resource analyses and the need is merely to 
gain experience in the use of better tools—a 
bench saw, when needed, rather than a broad 
axe, 
Resource managers often put pressure on re- 
searchers and technical staff men to SIM- 
PLIFY, to provide a set of cookbook rules that 
always work and are easy to follow. We prefer 
to operate on the following principle: 
You can simplify in a meaningful way, 
only that which you truly understand. 
Understanding requires that you look at the 
small pieces. When these are figured out, it is 
usually quite easy to put them together into 
larger, “more practical packages.” Attempts at 
simplification ahead of understanding are 
likely to lead to obscured truth and false con- 
clusions. The manger is left in the dark, and 
funds may be wasted in analyses based on ei- 
ther oversimplification or untimely attempts at 
simplification for ill-conceived utilitarian pur- 
poses. 
It is important for users of the output from 
ecological resource analyses to understand that 
if the specific landscapes are inherently com- 
plicated, their descriptive legends and mapped 
representations will appear somewhat complex 
—BECAUSE THEY ARE! Where landscapes 
are represented by broad expanses of nearly 
identical kinds of land, their cartographic rep- 
resentations are simple—often appealing to the 
practical eye. In contrast, information the 
manager may need is lost if the former kind of 
landscape is oversimplified in its legend and 
cartographic representation. 
When the ecology of an area is well under- 
stood and when the ground truth-photo image 
relations are worked out within the framework 
of this understanding, it is both possible and 
often desirable to develop mapping legends 
that simplify or generalize the intricate ecolog- 
ical patterns in the landscape. This permits 
generalization or the presentation of informa- 
182 
tion with varying levels of cartographic detail. 
For example, we are working on a resource 
analysis procedure and mapping legend that 
may be carried out at three levels of general- 
ization. By working from specific to general in 
legend development, we are reasonably assured 
that each succeeding level of generalization 
will be compatible with the previous level. 
These concepts should be followed in the prep- 
aration and use of mapping legends for ecolog- 
ical resource analysis. Unlike in the past, it 
will be possible to start with a level of gen- 
eralization appropriate to anticipated manage- 
ment intensity and then to update the analysis 
and mapping to meet growing needs for re- 
source information without making a com- 
pletely new resource analysis. Under this 
concept, resource analysis and subsequent ac- 
tivities to monitor the effects of management 
practices can produce a growing reservoir of 
resource data on a permanent ecological base. 
Because this kind of information is ecologically 
rather than land-use oriented, it can indeed 
serve multiple-use rather than single land-use 
objectives. 
Ecological Concepts 
In contrast to many other photo interpreta- 
tion and resource analysis procedures, here the 
point of focus is the entire community of 
plants occupying each ecologically different 
kind of land. These communities integrate the 
separate growth factors impinging on the 
plant community and give a biological expres- 
sion, through the structure and components of 
the community, of the net effect of all environ- 
mental factors or of the ecological site. Thus, 
the plant communities provide the best and 
most obvious basis for delineating ecologically 
comparable landscapes on aerial photography. 
The photo interpreter must have a working 
knowledge of these communities to assign 
meaningful identifications to each delineation 
and to produce a map of maximum usefulness. 
The following supporting premises, concepts, 
or principles have been important in our work. 
These have been selected from a longer list 
which we have amplified where needed (Culver 
and Poulton 1968). 
(1) Similar plant communities are, in fact, 
repeated across the landscape and show the 
resource analyst where the net effect of land- 
form, geology, climate, soil, and history of use 
is essentially the same. 
(2) Vegetation has become well adapted to 
disturbance through the evolution of its com- 
ponent species. Therefore, it shows a strong 
tenacity for its environmental niche, persist- 
ence of its characteristics (particularly species 
presence), anda strong recovery potential after 
disturbance. Thus, the key indicators tend 
