Plants, trees with a lot of pith?
I'm looking for plants, including trees, that have a lot of pith, and also maybe an inch or more across the stem. So far, all I can think of is ailanthus tree, cattails, and I think the yucca that grows wild here in the midwest US and also is planted in gardens. Maybe you can help me think of more, in case I need to try several.
I'm hoping to use sections of pithy stem on top of pokey wire pieces that I use as supports in our mostly ornamental garden that is open to the public. The purpose is to protect people from getting scratched or snagged. The wires are those H-shaped supports for corrugated roadside signs that solicit run-down houses to buy, diabeteic test strips, weight-loss schemes, and so on. Presently, I have plastic toy golf balls on the pokey ends, but want to use something biodegradable and free. So, pithy stems cut into two inch sections is my idea.
So, do you know of any other pithy stems? Or have any other ideas for caps on the wire ends?