johngood_____ writes
dont know what type of bamboo it is, but it has small thin leaves is quite
common around the london area, and it has the characteristic of folding its
leaves up very small and very quickly the moment the soil gets at all dry.

my specimens have just flowered and i've just been told that it will now
die. where is the logic in that?

There's a lot of logic in it. The purpose of the plant is to reproduce
itself (rather than simply to grow). All annuals grow, produce flowers,
produce seeds, die. Biennials grow one year, produce flowers then seed
the next, then die (lettuce bolting is an example). There are many
perennials in which the plantlet which has produced the flower spike
dies, even if the rest of the plant continues.

Animals can do the same. A lot of insects die off as soon as they've
reproduced.

The basic logic is that if there is an unfavourable season (eg cold
winter, hot dry summer), it's a lot easier to survive it in seed form
(or as an egg or chrysalis) than as a growing plant or an adult moving
around.

Other techniques are, of course, bulbs or hibernation.

--
Kay