The American Bamboo Society concludes that in almost every situation where bamboos are problematic, especially in urban and suburban settings, it is because people have not planted them properly, have not maintained them properly, or have not disposed of them properly. They issued a statement in 2012 that says that bamboos generally have low potential for invasiveness due to their rare flowering, but recognizes that some running bamboos can be aggressive spreaders and form large stands if left to their own devices. This is not right, as has been pointed out by the American Bamboo Society. They made no differentiation between different bamboo species, and as a result all bamboos are considered as a threat. Personal communication with focal persons in DG Environment in Brussels and colleagues in Headquarters of the International Union for Conservation of Nature (IUCN) in Switzerland made it clear that Europe is worried about the potential invasiveness of certain bamboo species. While the Regulation at this stage only lists a small number of species, there is concern about bamboo. The backbone of the legislation is the list of harmful invasive species (a ‘black list’ approach), namely ‘‘Invasive Alien Species of Union Concern,’’ selected only among species that are alien to the EU and that are identified as invasive through a detailed risk assessment. Unlike EU Directives, EU Regulations become national law without having to be transposed. The text, published in the Official Journal of the European Union on 4 November 2014, is in the form of an EU Regulation (Regulation 1143/2014), and becomes immediately enforceable law in all EU Member States on 1st January 2015. The European Union has recently agreed a legislative text on Invasive Alien Species. It is also possible that rhizome pieces could break off along river banks during floods or heavy rains and be transported downstream, but this type of dispersal is rare. Running bamboos may extend their rhizomes from a few centimetres to several metres in a growing season, and this is often considered invasive behavior. Most temperate woody Bamboos reproduce usually by rhizome growth. Studies reported from USA suggest that dispersal away from the parent population is a relatively rare event. Although many bamboos have small bristles adjacent to their seeds, which may allow animals to accidentally transport them, this is not a very effective dispersal mechanism. Much of the seed may be eaten by birds or rodents, but some will germinate and reestablish the clump. In general, when bamboos do flower and produce seed, most of the seed falls near the parent plants. With few exceptions, they have clumping rhizomes and their flowering cycles range from 7 to 60 years. The tropical woody bamboos occur in tropical and subtropical zones in Central and South America, Africa, Asia and Australia. Moso bamboo plantation in Anhui Province, China
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