True G-13, or Government Indica Strain 13, is a pure Indica strain that appeared sometime in the 70s or 80s. After years of crossbreeding, however, the current G-13s generally found in dispensaries are unlikely to be pure Indica. Today's G-13 strains are typically 70% Indica and 30% Sativa.
G-13 produces a powerful body stone, typical of Indica strains, that will make users feel lazy and lethargic. It also has strong cerebral effects often described as euphoric. Experienced users claim this strain makes them more focused and creative before the couch-lock feeling sets in. The strain also possesses typical downsides associated with Indica strains high in THC, including dry mouth and eyes, dizziness, paranoia, and some anxiety.
The G-13 strain can be used to medicate throughout the later part of the day, easing chronic aches, pains, and muscle spasms. Its mood elevating effects may help battle stress, anxiety, and depression. Some find that it assists with insomnia. It is also used by patients to combat the effects of eating disorders, seizures, and nausea.
G-13 is believed to have originated in a research facility in Mississippi in the 60s or 70s, where, with the help from the University of Mississippi, pure Afghani Indica clones were used to attempt the creation of a super Indica strain. As the story goes, Neville Schoenmaker convinced someone working there to bring him a cut from one of the strains, labeled G-1 to G-23. G-13 was chosen as the most stable. This strain flowers for six to eight weeks to produce a reportedly high yield and works very well in a Sea of Green. Unfortunately, true G-13 is a rare find as it is available in clone form only.