On a recent Saturday, Jarrett St. Amand loaded his SUV with metal tins filled with CBD-infused cream, gathered his canna-buddies, and drove west to Adelanto, California. Their destination? Burning Treez Festival, a large cannabis consumer music festival. The former Marine who served in Operation Restore Hope in Somalia in 1992 has been hardcore promoting his Jefro's Botanicals, which includes two wellness creams, at pot and music shindigs across the Southwest. His first cream, Jefro's Copper…