As you enter the jigoku area and begin to smell the sulfurous gases coming from deep within the earth, you might be wondering how plants could possibly live here. Yet as you can see, there is a unique, thriving ecosystem all around you.
　Noxious gas, water temperatures of nearly 100-degree Celsius, and highly acidic soil—the plants of the jigoku are adapted to this challenging environment. The tallest plant capable of growing here is the akamatsu, or red pine. Below them are shrubs such as Hawk’s claw peppers (takanotsume) and several species of azaleas, such as the miyamikirishima azalea, which blooms with pink flowers in late April. Other plants include the twisting red trunks of the Oval-Leaved Lyonia (nejiki) and the fruit-bearing shashambo, a low shrub in the same family as blueberries.
　Plants can survive even right next to the bubbling water and gas vents. Here you can see bunches of maiden silver grass (susuki) and tsukushitentsuki, ordinary-looking grasses only found in hot-spring areas like this.