The pot leaf, with its iconic odd-numbered spears, is probably the most widely recognized botanical image in the world. It owes this visual fame partly to the rise of stoner culture over the last half-century, but the plant is also indebted to countless ancient and Medieval artists who were inspired to depict it in religious and scientific illustrations.

Much like their modern 420-friendly brethren, these ancestral ents were fascinated by the simple beauty of the cannabis leaf. It's difficult to definitively trace their visual tributes all the way back to the earliest example, however, mostly because cannabis use predates written culture.

Cannabis sativa has been farmed by humans for 12,000 years as hemp, and archeological evidence suggests the recreational, medicinal, and psychoactive properties of marijuana have been understood for around half that time. (Reminder: Hemp and pot are different strains of Cannabis sativa; the former is generally industrial while the latter has higher levels of tetrahydrocannabinol, or THC, and is generally medicinal or recreational.)