Tetrahydrocannabinolic acid (THCA) is just not your regular THC. It's the cannabinoid precursor to THC. When it's exposed to gentle or heat, it undergoes a course of action termed decarboxylation, which leads to it shedding its carboxyl group and turning it into THC. With no THCA, there wouldn't be THC. https://jamesn901ayx1.blog-gold.com/profile