Wednesday, May 6, 2009

Commercial timber

Timber is harvested from cultivated and wild stands and some of the larger bamboos, particularly species in the genus Phyllostachys, are known as "timber bamboos".

[edit] Ornamental bamboos

Many bamboos are popular in cultivation as garden trees. There are two general patterns for the growth of bamboo: "clumping" (sympodial) and "running" (monopodial). Clumping bamboo species tend to spread slowly, as the growth pattern of the rhizomes is to simply expand the root mass gradually, similar to ornamental grasses. "Running" bamboos, on the other hand, need to be taken care of in cultivation because of their potential for aggressive behavior. They spread mainly through their roots and/or rhizomes, which can spread widely underground and send up new culms to break through the surface. Running bamboo species are highly variable in their tendency to spread; this is related to both the species and the soil and climate conditions. Some can send out runners of several meters a year, while others can stay in the same general area for long periods. If neglected, over time they can cause problems by moving into adjacent areas.

Bamboo foliage with black stems (probably Phyllostachys nigra)

Bamboos seldom and unpredictably flower, and the frequency of flowering varies greatly from species to species. Once flowering takes place, a plant will decline and often die entirely. Although there are always a few species of bamboo in flower at any given time, collectors desiring to grow specific bamboo typically obtain their plants as divisions of already-growing plants, rather than waiting for seeds to be produced.

Regular maintenance will indicate major growth directions and locations. Once the rhizomes are cut, they are typically removed; however, rhizomes take a number of months to mature and an immature, severed rhizome will usually cease growing if left in-ground. If any bamboo shoots come up outside of the bamboo area afterwards, their presence indicates the precise location of the missed rhizome. The fibrous roots that radiate from the rhizomes do not grow up to be more bamboo so if they stay in the ground, that's not a problem.

The second way to control growth is by surrounding the plant or grove with a physical barrier. This method is very detrimental to ornamental bamboo as the bamboo within quickly becomes rootbound--showing all the signs of any unhealthy containerized plant. Symptoms include rhizomes escaping over the top, down underneath, and bursting the barrier. The bamboo within generally deteriorates in quality as fewer and fewer culms grow each year, culms live shorter periods, new culm diameter decreases, fewer leaves grow on the culms, and leaves turn yellow as the unnaturally contained rootmass quickly depletes the soil of nutrients, and curling leaves as the condensed roots cannot collect the water they need to sustain the foliage. Concrete and specially-rolled HDPE plastic are the usual materials used. This is placed in a 60-90 cm (2-3 feet) deep ditch around the planting, and angled out at the top to direct the rhizomes to the surface. (This is only possible if the barrier is installed in a straight line.) Strong rhizomes and tools can penetrate plastic barriers with relative ease, so great care must be taken. Barriers usually fail sooner or later, or the bamboo within suffers greatly. Casual observation of many failed barriers has shown bursting of 60 mil HDPE in 5–6 years, and rhizomes diving underneath in as few as 3 years post install. In small areas regular maintenance is the only perfect method of controlling the spreading bamboos. Bamboo in barriers is much more difficult to remove than free-spreading bamboo. Barriers and edging are unnecessary for clump-forming bamboos. Clump-forming bamboos may eventually need to have portions removed if they get too large.

he bamboos En-us-bamboo.ogg listen are a group of woody perennial evergreen (except for certain temperate species) plants in the true grass family Poaceae, subfamily Bambusoideae, tribe Bambuseae. Some are giant bamboos, the largest members of the grass family. Bamboos are the fastest growing woody plants in the world. Their growth rate (up to 60 centimeters (24 in.)/day) is due to a unique rhizome-dependent system, but is highly dependent on local soil and climate conditions.

They are of economic and high cultural significance in East Asia and South East Asia where they are used extensively in gardens, as a building material, and as a food source.

There are more than 70 genera divided into about 1,000 species.[1] They are found in diverse climates, from cold mountains to hot tropical regions. They occur across East Asia, from 50°N latitude in Sakhalin through to Northern Australia, and west to India and the Himalayas.[2] They also occur in sub-Saharan Africa, and in the Americas from the Southeastern United States[3] south to Argentina and Chile, reaching their southernmost point anywhere, at 47°S latitude. Major areas with no native bamboos include Europe and Antarctica.[4]