G-13 is a strain of cannabis. G13 has two phenotypes: indica and sativa. It was bred from an Afghani strain, which typically indicates an indica or indica dominant strain because Afghani landraces are indicas. Since it was taken as a clone, almost the only things available are crosses such as G13 x Piney and G13 x Hashplant or so-called "selfed" or sibling crossed seeds such as G13 IX. Selfing involves stressing a female plant (cannabis is a dioecious plant meaning that male and female flowers grow on separate plants) to the point that it becomes a hermaphrodite, producing male flowers that then pollinate the female flowers. Spraying a female plant with gibberillic acid can also cause stamen production. Caution should be taken not to inhale the mist. G-13 can also be linked to a strain of cannabis referred to as G-14, and is sold in certain sections of Southern Africa. According to legend G-13 is the "mother plant" of G-14. G-14 is easily identified as a very strong wild variety strain of cannabis with a potent "fruity" smell.
The origin of G-13 is likely one of the most perplexing of any strain, making it the subject of many urban legends. According to some accounts, in the late ‘60s and early ‘70s the CIA, FBI, and other government agencies collected the best strains from around the world. At a top-secret installation at the University of Mississippi, they bred many new super hybrids. Allegedly, a single cutting of this plant was liberated by an unnamed technician and bred for the masses. The cut, G-13, was said to be the 13th, and one of the most potent, in a series of pure Afghani strains. The other explanation of the name is that it is a code name, with "G" standing for "Government" and "13" standing for the 13th level of the alphabet, M, for "Marijuana," which would make the whole name "Government Marijuana."
The facts, however, provide no substantiating evidence. Although cannabis researchers at the University of Mississippi did assemble a world-class cannabis collection during the late 1960s and early 1970s, there is no evidence that these researchers were ever involved in breeding high quality marijuana.
G-13 is an Indica-dominant cannabis strain that generally has 70 parts indica to 30 parts sativa. It has dense, sticky buds. G-13 has a crisp pine smell with chemical and citrus apple scents. While the average THC content of G-13 is constantly debated, it likely exceeds that of most other strains. Many reports state that this strain can reach up to 28% THC levels,however even the highest THC levels rarely surpass 20%. An estimate of between 15-20% THC levels is more reliable.[clarification needed]