The above photos are all Californian native species, taken in their natural habitats. Many of these are posted on CalFlora through their affiliation with CalPhotos.
I find that photography can provide a viable alternative to collecting and pressing specimens for learning a flora. It is not a substitute for what herbaria can provide towards describing a flora and sorting species, but it is a very cheap and beautiful way to study the extant species of an area.
Field botany is a dying art, and one that must be maintained. Professional field botanists have a wealth of knowledge that is unwritten, and in many cases unwritable. This knowledge must be transmitted or it will be lost. Recently there has been a recognition among ecologists of the importance of simply knowing the plants. Couple this recognition with the current debate over the newly proposed "PhyloCode" and many people are becoming interested in taxonomy. This gives me hope.