I believe when most people hear the word RoundUp (especially so far in this thread) they're only thinking of glyphosate. That was all RoundUp used to be and what people still assume when they hear the brand name. But over the years there have been other chemicals mixed with it in different blends of Roundup that will kill bees and other bugs. Oils, acids, "stickers" and other additives put in to change how glyphosate works.
About 18-20 years ago some landscapers started using Roundup with very small amount of Scythe mixed in to get quicker weed kills. Scythe is pelargonic acid and some oils. This showed effects in literally 1 hour by wilting the plant and allowing the absorption to be quicker. The oil in it helped make it rainfast in case it started to sprinkle after you left the property. RoundUp got news of this mixture and came out with it's own similar blend of same chemicals about 16-18 yrs ago. My company had 25-28 employees and did all commercial accounts and had all licenses. A commercial distributor called Lesco (now owned by John Deere) was given batches of this new RoundUp for trials in the field. We were given enough to make about 300 gallons and asked to report back to Lesco on how it worked.
This new commercial Roundup was very powerful. You could spray clover on a parking lot and by the time you got around the building back to where you started, the clover was already wilted in like 10 minutes, like wilted lettuce! On hotter days around 90 degrees the mixture would actually start to gel up in the sprayer into what looked like diluted mayonnaise, or shampoo. The sprayer pretty much couldn't spray it and would just sputter out thick white gel. The strange thing is that once it cooled down under about 90 degrees or so, the gel went back to liquid again. Some guys put the sprayer in the truck with the A/C and by the time they got to the next location, it was usable liquid, not gel. I can promise you 100% that when it was still a sprayable jelly it did indeed kill entire wasp nests with ease. The gel stuck to them and they were dead in less than an hour right under the nest.
We told Lesco about how powerful it was at killing weeds, and the gelling problem, but never brought up how we sprayed wasps because there wasn't much reason to. Probably 8 months later, maybe longer, RoundUp put out the same basic commercial product and the Lesco distributor said they fixed the gelling problem which my understanding had to do with the strength of the acid in it. By the way, this was pelargoni acid (same as Scythe mentioned above). We started using the new RoundUp every day. They also made a granular form that was slightly different and sold in pouches.
The new mixture wasn't as strong, but it would still gel up maybe 50% when it got really hot, like 95+ degrees. Because we were now using this new mixture all the time, more things become apparent. Two guys had a bad looking infection on their index fingers. On the first guy his finger was red and peeling really bad. I thought it was nail fungus, but it kept getting worse. He went to the doctor and the doc said it wasn't fungus. Turns out his sprayer had a leaky gasket and was getting a little on his finger and basically eating away the skin. Fixed the sprayer, finger healed up. Happened to the next guy and we knew what it was immediately. As mentioned in the other post, the sprayer holders were next to the front mowers and the nozzle hung over their decks. Trucks always get loaded the same way and within a few weeks the paint was bubbling up under the sprayer nozzles down to shiny metal. Keep in mind commercial mowers are designed to sit in the rain all day without any paint issues happening. The new blend also still killed wasps, but not like the previous stuff. You could spray them and some would fly away, but others couldn't and just walk around under the nest and slowly die without being sprayed again.
Here's what I think some of you guys are missing. Glyphosate or pelargonic acid won't kill bees by themselves. But when Monsanto mixes them together, THEN adds a surfactant sticker that significantly increases absorption on the target, THEN adds an oil to keep it stuck on the target to make it rainfast........it's no longer just glyphosate........but people will still call it "RoundUp". So yes, there are RoundUp mixtures that will kill bees, but it's not just glyphosate like some people must be thinking. I know residential can buy this same type of Roundup mixture, but I don't think it's as strong as the commercial blend. I could buy some and see though.
