THCA vs. Delta-9 THC
Same plant, different stage. THCA is the raw form cannabis produces naturally, non-intoxicating until it's heated. Delta-9 THC is what THCA becomes once that heat hits it, through smoking, vaping, or any other form of combustion. One doesn't exist without the other, it's just a matter of before and after.
Here's the part that actually matters legally: hemp law draws the line at Delta-9 THC content, not THCA. Anything testing under 0.3% Delta-9 THC by dry weight qualifies as federally legal hemp, THCA percentage isn't part of that equation. That's how a pre-roll can be sky high in THCA, convert into a full Delta-9 experience once lit, and still be completely compliant on paper.
So when you're smoking THCA flower, you're not skipping Delta-9 THC, you're just getting there a different way.