dry, brown, crumbly, or otherwise low quality weed.

bam, being short for bammer, and schwag meaning weed.
Bob: I just got a $50 ounce!

Fred: How? Was it some bam schwag?

Bob: Yeah, but I'll just sell this shit to some stupid freshman and buy myself some chronic with the profit!

Fred: Legit. We'll burn it fat.
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