Understory vegetation is the plant life growing beneath the forest canopy. Understory plants are usually seedlings and saplings of the adult canopy trees but may also include other shrubs and herbs such as raupo, flax or carex grasses. Plants in the understory receive less direct sunlight than those above and must therefore be tolerant to shade. River banks with limited understory can be prone to erosion leading to increased levels of sediment in the water. A developed understory, as part of intact riparian forests, can provide shade to fish and macroinvertebrates in the river and habitat for inanga (whitebait) to spawn.