Adkinson v. State, 236 Ga. App. 270, 271 (1) (a) (511 S.E.2d 527) involves, inter alia, violations of the Georgia Controlled Substances Act and possession by Adkinson of marijuana found in his car. At trial, the GBI chemist testified that although he thought the green leafy material was marijuana, he did not test it, so he could not testify beyond a reasonable doubt that it was marijuana. One narcotics investigator testified that there are a lot of leafy substances that look like marijuana but are not marijuana. This evidence does not exclude every reasonable hypothesis save that of the guilt of the defendant. See Jackson v. Virginia, supra. "It follows that it would be a reasonable hypothesis that the material found could have been hemp and hemp plants do not authorize convictions." Phillips v. State, 133 Ga. App. at 393 (1974). Reversal under these facts was required. It does not follow, however, that no lawful conviction could ever be obtained absent a scientific test of the substance, and to the extent that Atkinson's argument implies that evidence must be scientifically conclusive in order to identify marijuana or other drugs, it is without merit.