It might be an application for the "hot stretched wire" I saw someone make.
Nichrome wire, with resistance such that a 1-foot length gave enough Ohms that the wire only heated up and glowed red, not white.
Stretched between two 2x4 uprights braced ~ 12" apart.
AN ON-OFF switch
Heat the tight-stretched wire, roll the plastic bottle along it, and only singe some roots while cutting the indented part off clean.
Maybe a deluxe model with a fuse or variable transformer like a large toy railroad set might have, designed to avoid home fires.
The web site that sold many different Nichrome wire types had some designed to heat up gently like heating pads, others designed to get REAL hot like clothes driers, and others designed to flash into vapor and INTENTIONALLY ignite anything close to them. Kind of like a primer charge for small solid rocket motors.
Or a "gun" style soldering iron plus a steady hand might let me melt a narrow line..
I'm just hoping that my indented grooves are shallow enough that I can bang out the root ball and re-use the plastic pot. If the root ball is really wound up tiogght, I WANT to unravel and disrupt it before planting.
I may be dreaming!
