The Ginga Forest is the home of the Gingaman. It is sealed off from the rest of the world, normal Humans can't enter it. In the second episode of the series, just as the Space Pirates Balban nearly succeed in drawing energy from the forest to use for the revival of Demon Beast Daitanix with no way for the new Gingamen to stop it, the Elder Orghi intervenes. Using a spell he transforms all the Ginga Forest into stone, which cancels out the Balban's device, but also turns himself and the other people into the stone with only the Gingaman unaffected due to getting out in time. Before he transforms into stone completely, Orghi gave a seed to Fairy Bokku that would be used to create Wisdom Tree Moak. Afterwards the petrified forest sunk beneath the lake.
In the finale, after Balban's leader Zahab was defeated for good, the Gingamen arrive to the site, where to their surprise, the Ginga Forest emerges from the lake, and the petrification was undone, restoring everything back to normal.
In Gokaiger, The Lost Forest, Basco and Sari penetrates the Ginga Forest where they intend to take the Greater Power of Gingaman. Their attack on Hyuuga is witnessed by the Gokaigers, who take Basco on and defeat him.