Jungle-like, invasive, a food source for pandas: these are a few perceptions people have about bamboos. Little do they realize hundreds of species of bamboo exist and provide building materials, tools, furniture and grain food to people around the world. If you garden, choose a clumping bamboo species rather than a running bamboo.
Bamboos are often considered the world's most ancient grasses according to "Bamboo for Gardens," with predecessors dating from 30 million to 40 million years ago. The modern bamboo species, Streptochaeta spicata, is an example of what paleobotanists believe ancient, early bamboos resembled. The book's author also reveals that chloroplast DNA studies suggest that the first bamboos developed in what is today South America.
Europe and Antarctica are the only two continents lacking any native bamboo species. The most species-rich areas for bamboo are, in descending order, southern Asia and the Pacific Islands, Tropical America and Africa. A bamboo species naturally grows as far north as Russia's Sakhalin region to as far south as southern Argentina. They grow from sea level to 14,100 feet in the Ecuadorian Andes, too. China boasts some 400 native bamboos, but only one in the U.S., Arundinaria gigantea.
Bamboos are grasses, members of the family Poaceae, and further classified by being either woody or herbaceous as based on the sturdiness of their stems, called culms. Herbaceous bamboos possess softer culms, tend to not tolerate dry conditions and are grouped into the subfamily Olyreae while the woody culmed, more resilient bamboos belong to subfamily Bambusoideae.
Gardeners often cringe when they hear of a landscape filled with bamboo, as it conjures an image of an invasive thicket of stems that are hard to eradicate. True, some bamboos do spread their rhizome roots outward to form groves. These are known as having leptomorph rhizomes, as in the case of running bamboos in the genus Phyllostachys. Other bamboos develop into more tidy, rounded clumps and are beloved by gardeners. These clumping bamboos have pachymorph rhizomes.
While flowers of bamboos and other grasses aren't particularly showy, they share a similar structure and need for wind to be pollinated. The great diversity of species of bamboos reveals that some woody bamboos reliably flower annually, it seems most others flower in lengthy cycles. The mechanisms that trigger flowering in bamboo remain poorly understood. Interesting stories of bamboo flowering cycles include that of Pyllostachys bambusoides, which flowered in 1840. It was believed to flower heavily again in 120 years, about 1960 to 1970, which is what happened in both Asia and in North America where plants grew in gardens according to "Bamboo for Gardens." Not all plants of a single species flower at once, lending confusion and mystery to the world of bamboos and their flowers.
After the infrequent and unpredictable flowering, bamboos yield seed grains called caryopses. The author of "Bamboo for Gardens" also shares that there are historical accounts in Japan and China of the copious production of bamboo seed grain ending famines in the 19th century. Size of seeds varies by plant species. Species Dendrocalalmus longispathus needs 68,000 seeds to equal a pound while Melocanna bambusoides needs only 32 seeds to reach that weight.