UB Knows his shit! I have never used any chemical root pruning techniques, but trust his knowledge and experience.
I grew up on a grain and potato farm and have lived in rural farming communities for the better part of my life and have seen more than enough serious Chemical safety infractions to put half the county in cuffs for reckless endangerment... But it's the status quo, the people who grow the food for the better part of the worlds populations aren't as concerned with the "Safety" of the final food product as they are with VISUAL quality and things such as protein content.
To fully explain ALL of the circumstances regarding the labeling of chemicals for use on food crops is truly a nearly impossible thing IMHO. Companies produce chemicals that produce the results the farmers want, not the other way around, this plus the huge disconnect between the two creates a confusing and possibly very dangerous atmosphere surrounding the entire industry.
Ex. An average sized family Farmer Bob Lobla wants a better way to stop his newest glyphosate resistant Bull Thisle strain from overtaking his prized soybeans(which after he harvests will be delivered directly into a facility containing MILLIONS of lbs of the source of everybody's favorite veggie burger...) gets the newest broadleaf burn down product on the market and applies generously across everything on the field, including the developing bean pods.
I like to think that these chemicals are 100% safe, but one look at the label of these products that have been recommended to unknowing growers would have even a completely illiterate person asking safety questions. The company wants to sell it, and I doubt that with the frequency of new products on the market that all of these products have been properly tested over a period long enough to be entirely sure that there is no long term effects because of human consumption.
Many growers intentionally use a product that isn't labeled for their crops and even mix chemicals because it still produces the positive effect, without the farmer having the slightest clue as to what kind of chemical processes are taking place inside the plants. Bob is happy because his soybeans might take first at the fair this year, and chemcom is happy with their money pile, and as long as nobody can trace the cause of their illness all the way back to Bobs blue ribbon beans the cycle continues.
My point? Unless you grow everything you consume organically yourself, you can't be sure just what kind of terrible things you may be bringing in to your body.
If you clowns are worried about something this low risk you should probably avoid anything on the shelves of most grocerie stores... Maybe do some research on commonly used agricultural chemicals to help widen your perspective, even a visit to a local ag extension office and ask for information. I think alot of people would be quite concerned to see what actually goes on in the production of their food sources.
Its like someone spitting on your double cheeseburger, only the spit is a stew of variouse chemicals and compounds in trace amounts, for your enjoyment...
much respect UB.. Haters gonna hate I guess