Stone mounds, part of the gardening system at Pouērua

The many small mounds are about 4 m across at their base. The functions of such mounds are difficult to determine. They may have served to clear the stony soils of the old lava flow so that the friable and fertile soils that resulted were more easily tilled. Alternatively, they may originally have consisted of heaped-up mounds of soils, organic compost and stones, on which plants were grown. The topsoils have subsequently been eroded away from the surface leaving a mound of stones which does not look as if it could have been gardened. A further possibility is that the vines of plants such as kūmara or yam were trained over the mounds. At top are some larger lava domes (about 25 m across). These have had stone stripped from their surfaces and placed in walls on their perimeter. At bottom and bottom right, a heavier fall of ash has reduced the need to create stone mounds. Here there are barely perceptible lines in the small valley floors which are either trench garden boundaries or track ways. Also showing are lines of stone walls constructed in the nineteenth century.