Mitragyna speciosa is an evergreen tree that can grow to a height of 25 m (82 ft) tall and the trunk may grow to a 3 ft (0.91 m) diameter. The trunk is generally straight and the outer bark is smooth and grey.
Overall though, metal is a much better option than plastic. In most cases, it is much more effective and reliable, and the right choice of metal will avoid the pitfalls of rust or weakness. Aluminium, steel and stainless steel are the three metal gutter materials for guards that homeowners can choose from.
The Best Materials to Cover your Greenhouse. 1  Glass: The traditional greenhouse covering, glass is the preferred material for permanence. It lasts indefinitely although it does become brittle with age. 2  Film Plastic: Film plastic is one sixth to one tenth of the cost per square foot of a glass covered structure.