I've always used dog fennel, cedar and pine rubbed on my cloths to help blend in...or step in a meadow muffin if it were fresh. I read an article last year about making your own cover scents that specified using materials that are indiginous to the area you're hunting in and when they were in season.
A funny story about cover scents...My long time hunting buddy, Richard, got the brilliant idea to use grapes as a cover scent because the grapes were so plentiful that year that the woods smelled like wine. He collected a good mess of grapes and put them and his hunting cloths in a garbage bag and smished them all together. After his cloths were well scented with "ole de grape" he hung them out to dry. When time came to hit the woods, Richard "dressed out" in his scented hunting cloths and headed out. Well, in Georgia, during the early archery season, it can be quite hot and sweaty and by the time Richard got to his stand, climbed the tree and settled in to cool off, it was apparent that the crop of yellow jackets was as aboundant as the grapes. Needless to say that was probably the least amount of time that Richard ever spent in his stand.
This happened quite a few years ago but is one of those stories that is revisited each year(at least once) around the club camp fire. Pat