Not sure who the respondent is doing work in Florida, but not everyone in 
Florida finds aerials to not be useful in canopied areas.  I, for one, use 
aerials daily for survey work.  They are used as basemaps to display GPS data 
collected or for use with GIS data so that an understanding of the landscape can be 
easily seen.  As far as canopy, distinction between vegetative groupings is 
often very useful, historic homesites for example often have distinctive 
plantings and arrangements of canopy, and vegetative signatures are also known 
(especially where the person responding-Dan- says he does work...) In South Florida, 
tropical hardwoods can be delineated with available 1 and 1/2 foot true color 
aerials.  These hardwoods are readily associated with shell middens and so 
can be used as a way of remotely locating prehistoric sites.  

Knowing the limitations, resolutions, etc. of aerials is the important thing. 
 Rather than using aerials in some instances it might be more appropriate to 
use landcover data, where analytical queries can be done in a GIS to select 
for certain vegetation signatures known to be associated with certain types of 
sites.  As for the topo data that the Florida person-Dan- refers to as 
available only in South Florida, it is actually available for the entire state, and at 
much finer scales than previously mentioned.  In some regions, lidar data 
(done for floodplain delineation) is available through water management districts 
and ACOE and provides extremely good topographic understanding of areas.  
Digital terrain models are also readily available for ArcGIS users from a variety 
of sources, and are free for the download.  I think that we should be 
cautious of discounting technologies, when using better analysis techniques (more 
than just 'looking' at maps and aerials), might be able to readily discern 
features and sites.  If we just say that the aerials in and of themselves are not 
very useful, we might not be very receptive to someone who says that in fact 
they are extremely useful. It is not so much the limitation of the aerials as it 
is the limitations of the reading of the aerials, and someone familiar with 
interpretation and use of these in GIS and RS programs can tease out detail that 
could be otherwise overlooked. 

If anyone would like sources for data or other suggestions for aerial use, 
feel free to write me off list.
Best,
Lori



Lori D. Collins, M.A.
Instructor/Undergraduate Advisor
University of South Florida
Department of Anthropology
813.974.0783
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