of UF resins, which emit volatile organic compounds (VOCs), is harmful to indoor air quality, bamboo flooring uses a relatively small amount compared with other materials, such as particleboards. Bamboo flooring products that avoid formaldehyde use are available, including some listed in the GreenSpec Directory. The panels are then heat pressed to cure the adhesive. The cured boards are then planed, sanded, and milled. Finally an ultraviolet curing lacquer is applied to the boards. Manufactured bamboo floors are typically made available in planks with either vertical- or horizontal-grain orientation. In vertical bamboo floors, the component pieces are stood vertically on their narrowest edge and then press laminated side to side. The effect is a lined, almost uniform look to the surface of the finished floor plank. In horizontal bamboo floors, the slats are arranged in a horizontal direction, on their widest edge, and then joined side by side with adjacent pieces using a high-pressure laminate system. The characteristic nodes of the bamboo are visible on the finished horizontal surface. Locking bamboo flooring is the easiest to install. Individual flooring planks have interlocking joints that click precisely into place. By combining plank alignment and color a lot of different styles can be produced. Strand woven bamboo flooring can be refinished with a clear-coat quite easily, however applying a stain on-site can be challenging. Environmental impact Bamboo is an eco-friendly, highly renewable source of material. As a grass, bamboo grows much faster than wood. Moso Bamboo is the primary species used for the manufacturing of flooring and plywood. Moso bamboo can grow up to in 24 hours and high in 40 to 50 days. It takes about 3–5 years for bamboo to reach full maturity. Traditional hard woods can take 20–120 years to mature. Bamboo can be harvested without the need to replant because the root system is left intact when it is harvested. The rhizome root structure has the ability to hold the soil in place preventing erosion. Rhizome root structures are horizontal stems that grow below the surface and help a plant reproduce vegetatively. Plants with rhizomes will colonize or spread laterally. In the United States of America, The Lacey Act recently strengthened the accountability in the sourcing of timber products. However enforcement is still in question. Bamboo reaches maturity in five years which is the optimal age to harvest. In a sustainably harvested forest only 20% of the forest