Yesterday I started talking about rhizome pruning, arguably the best way to control running bamboos.
Today a bit more about this, starting with the finished product! This is my Phyllostachys atrovaginata grove newly pruned, the trench visible as a loop of plowed earth surrounding the plant. Bamboo allowed inside the loop, not allowed outside!
The next bamboo on the south property line -- the one that's most in danger from bamboo escape because the plants seem to more readily migrate toward the sunnier, warmer south side -- is the Phyllostachys propinqua 'Beijing' in the back corner.
This is my newest planting and is performing so well, sizing up quickly and staying quite upright. Drooping culms was the reason that I removed the Ph. glauca 'Yunzhu' that previously grew in this spot. Can't have those culms hanging into the neighbor's yard!
A detail about the trench itself: it's only four inches (10cm) wide or so, just wide enough for the mattock to fit. When I unearth an escaped rhizome I use the pruners to cut it at both walls of the trench, resulting in lots of little rhizome sections lying around:
None of these will grow into a new plant regardless of what you might have heard about bamboo rhizomes. Viable divisions need good feeder roots and at least two viable node buds -- one to create a culm and one to create a new rhizome. These tiny sections might have a single bud but have a 95% or higher chance of dying, even if potted and babied.
The soil back here around this plant is the best in my yard, and is especially loose and lovely in the trench around this plant. One whack with the mattock revealed this:
Can't tell what's going on there? Here's a closer view:
It's a toad that had buried itself in the friable soil to hibernate for the winter. I missed him by a couple of inches! Discovering it really shook me up as I would have easily chopped him in two with the sharp mattock. Close call but thankfully no harm done.
I took a break to sit on a makeshift bench (plank spanning two stumps) and enjoy the sunlight through the Pleioblastus viridistriatus bamboo:
Those few remaining green leaves make things more interesting! I'll be mowing this one down soon, and will prune around it at the same time. (I don't trench around these groundcover bamboos as I tend to change the boundaries of their beds quite often. I just cut through the rhizomes with a spade.)
That wrapped up the bamboo work for Sunday.
Yesterday (Monday) I moved to the north property line and pruned the black bamboo (Phyllostachys nigra) -- not shown here -- and then moved on to the Semiarundinaria fastuosa 'Viridis'.
This bamboo is the most marginally hardy I grow (well, maybe tied with the Ph. nigra) and really took a hit the last couple of years with winter lows in the negative single digits F. This left many dead culms:
So before pruning around this one I used the loppers and removed 50-75 of them:
Looks much nicer, but so much thinner:
I'm hoping it will add quite a few new culms after our mild winter. Can't wait for shooting season to start!
That extra work sapped my energy and I could only get halfway around this planting -- and it sends rhizomes deeper than most of the other bamboos so really needs to be thoroughly attended to. I'll be finishing that up later this week. Then only three more big ones to prune and I can start on the smaller ones...
Why did running bamboo have to be "my" plant?