Fig. 4. Field testing and schematic illustration for cross hybridization between genetically modified (GM) and wild-type (WT) Zoysia grass and it relative weed species as a function of distance. (a) GM Zoysia japonica tillers (illustrated with white circle). (b) WT grass group containing Zoysia japonica (Zj), Zoysia matrella (Zm), Zoysia sinica (Zs), Lolium perenne (Lp), and Poa pratensis (Pp). (c) Hexagonal arrangement illustrating a GM test area shown in (a); orange, 3-m radius; blue, 6-m radius; black, 9-m radius).