Bamboo can be utilized as a building material as for scaffolding, bridges and houses. Bamboo, like true wood, is a natural composite material with a high strength-to-weight ratio useful for structures. Bamboo has a higher compressive strength than wood, brick or concrete and a tensile strength that rivals steel. Bamboos are some of the fastest-growing plants in the world, due to a unique rhizome-dependent system. Certain species of bamboo can grow 35 inches/890 mm within a 24-hour period, at a rate of 0.00003 km/h (a growth of approximately 1 millimeter (or 0.02 inches) every 2 minutes).