depending on the area..i have an area that holds good deer that stay local all year they don't migrate..i scout them yearly and usually use trail cams starting now to get there patterns down...for those that migrate i usually will start once the temp stays the same (mid june) i will be in the woods seeing where they move to and from....water is going to be a big key for me this year in CA...not too much rain and lots of season streams have been dry for quit a while..