High Times tells about the lineage:
While Sensi say the exact lineage is a closely-guarded secret, it is accepted that Jack Herer is a 3-way hybrid of Skunk #1, Northern Lights #5 and Haze. The precise lineage is probably Haze x [Northern Lights #5 x (Northern Lights #5 x Skunk #1)] which suggests that Sensi began by selecting a male from their NL5 x SK1 seedline (AKA Shiva Skunk) and backcrossing him to the NL5 female cutting. As Sensi purchased Neville's breeding plants, they had both the Haze A and C males, so it is likely that they then chose a female NL5 x (NL5xSK1) plant and pollinated it with one of the Haze males to create Jack Herer., this would make Jack 50% Haze, 37.5% NL5 and 12.5% SK1. This gives Jack Herer a similar composition to Super Silver Haze and Mango Haze which are 50% Haze, 25% NL5 and 25% SK1.
