I had a couple of old rhubarb plants dug up with a excavator today. I am going to divid them and replant. The roots in these plants are HUGE and are more like octopus tentacles. so, my question is... Do I have to dig three feet down to get these plans back in or can I just cut these extra large roots off at little detriment to the plant?
You can do anything to the roots; as long as the crown remains intact, rhubarb will transplant successfully.
For any transplant, more root is better. For rhubarb, like the above post said, as long as the crown is intact... . Nice rich soil (lots of manure, compost), and keep it moist. Rhubarb will grow like a weed. I transplanted mine at the end of May after clear picking at the end of April a couple of years ago, and still got 3 more pickings over the summer. I also got plants that I did not know I had moved (thought I got 3, which is what I had originally planted, but wound up with about 6 - it grows from broken bits of root)