Moso bamboo does not advance outwards in a haphazard way. It advances some metres into areas it likes, sending up pioneer culms in the first year to form a kind of picket. Here’s the eastern picket of my grove.
The grove as a whole doesn’t move out like this. Rather, it has a “ragged edge” because moso is a gourmet. If it doesn’t like an area of ground it won’t risk a picket, just a few straggly poles. For example, where the grass is short or the ground is bare, it won’t form a confident picket. Even long grass on a hot slope is not interesting to moso. Lots of lantana and very young wattles is a good mix, though if the lantana is a bit bare from frost, even that is enough for this temperamental gourmet to refuse an advance into new ground.
One frustration of growing moso is the belief by neighbours that it will somehow invade their properties. If only! Another frustration is the insistence by visiting experts that things should be done a certain way, when, quite clearly, the way doesn’t work. People who are far more competent and knowledgable than me will insist on planting moso “out”, ie. in full sun and on rich flats. Instead, it needs to be started on a cool south slope, protected, but not overwhelmed, by lantana and maybe the branch of a big wattle. Even after twenty years, a grove needs good cover and drainage to advance.
This year, on the south-west edge, it moved into a well overgrown patch of red soil. The growth of one new pole in that area was amazing. The yard-a-day which is achieved by some healthy culms in the last days of their growth was achieved as an average by this one culm. It’s already branching after less than two weeks! (No photo. It’s just too thorny and tick-ridden in that patch of ground!)
Anyway, the ‘boo is lush this year, the wallabies know it and have been feasting on any shoots that I neglect to protect. Can’t you just taste the chlorophyll?