Juncus bufonius Juncus bufonius seeds in a 1/4 tsp (2 cm diameter). Juncus bufonius mature (brown) and immature (green) fruits. Juncus bufonius seedlings. Juncus bufonius seedlings growing in 48-cell liners at the Berry Seed Bank research greenhouse located in Portland, Oregon. Juncus bufonius rootball for seedlings growing in 48-cell liners at the Berry Seed Bank research greenhouse in Portland, Oregon. Juncus bufonius seedlings growing in 4-inch containers at the Berry Seed Bank research nursery in Portland, Oregon. Juncus bufonius seedlings growing in a 4-inch container at the Berry Seed Bank research nursery in Portland, Oregon.