I will second Dave's recommendation of "The Changing Mile" by Hastings and Turner (1965), and there is actually a second volume, "The Changing Mile Revisited" by Turner et al. (2003) which continues the sequence with a third set of before-and-after photographs at the same locations. I have always enjoyed repeat-photography studies and these are some of the best out there.
Dave, I want to thank you also for your succinct explanation of the role of cattle in the proliferation of mesquite in the Southwest. It sounds trivial, but it had never made sense in my mind until now (clueless Easterner that I am), despite my graduate training in botany and ecology.
-Philip Marshall
Dave Peterson Wrote:
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> You should look at a copy of the book "The
> Changing Mile". It documents the changes in
> vegetation throughout Arizona over the past
> century using comparative photography (in fact it
> gave me the idea to do the same with railroads).
> Many grassland habitats have been completely
> replaced with mesquite. Cattle are strongly
> implicated due to their ability to scarify the
> seeds. Its pretty amazing (and sad) to see the
> changes in vegetation.