Nate,
Garters are very cool indeed, just make sure if you plan to take a wild snake that it is legal in your area (quite frankly I personally wouldn't pass judgement either way, but don't want you getting in any undue trouble), but even if it is legal there are good reasons to aquire captive bred and born anyway and they are regularly available and very reasonably priced, but if you do decide to take a wild caught in, you will probably have better success with hatchlings and raising them up, than an adult, it's a very stressful change for an wild adult that is set in it's ways. Maybe you have already considered these things, and not I'm not trying to rain on anything or curb your interest, I've just crossed that bridge more than a few times over the years, sometimes with regrets.
Good luck and post picts if you do get some, and thanks for sharing the field pics, nice looking snakes for sure, keep them coming.
Jeff
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Jeff Benfer
1.0 cinnamon pastel Python regius
1.1 pastel Python regius
1.1 mojave Python regius
0.3 normal Python regius
1.3 Terrapene carolina thriunguis
2.3 Terrapene carolina carolina
4.1 Kinosternon baurii
1.1 Malaclemys terrapin terrapin
2.2 double het albino and anerythristicThamnophis sirtalis parietalis
1.0 anerythristic Thamnophis sirtalis parietalis
2.3 Iowa snow Thamnophis radix
0.2 het Christmas albino Thamnophis radix
1.1 double het cherry erythristic, albino Thamnophis sirtalis sirtalis
1.1 melanistic Thamnophis sirtalis sirtalis
2.0 66% het snow Thamnophis sirtalis sirtalis
1.1 triple heterozygous for amelanistic,carmel, and stripe Pantherophis guttatus
0.1 anerythristic motley Pantherophis guttatus
0.1 butter p.h. stripe Pantherophis guttatus
0.1 carmel stripe p.h. amel Pantherophis guttatus
0.1 amelanistic p.h. carmel,stripe Pantherophis guttatus