Robert F. Kennedy Jr. on glyphosate: what the evidence says · JRE #2461
SUBJECT: GLYPHOSATE
The short answer
Kennedy claims a specific South Texas onion farmer's per-acre weed-control costs dropped from $1,500 to $300 by switching from glyphosate/manual labor to a laser-weeding machine. The specific dollar figures Kennedy cites for an unnamed South Texas onion farm ($1,500/acre dropping to $300/acre) cannot be independently verified; the operation, its acreage, and its exact costs are not named or documented in any public dataset, and the figures resemble the kind of case-study numbers laser-weeding vendors such as Carbon Robotics circulate in marketing materials.
Not a true/false call. Every claim is logged with its sources; read the exhibits below.
She was paying $1,500 per acre for pesticides, for mainly glyphosate and for a manual labor. And now with this machine, it's $300. She's saving over $1,000 an acre.
What the evidence says 01 / RECORD
The specific dollar figures Kennedy cites for an unnamed South Texas onion farm ($1,500/acre dropping to $300/acre) cannot be independently verified; the operation, its acreage, and its exact costs are not named or documented in any public dataset, and the figures resemble the kind of case-study numbers laser-weeding vendors such as Carbon Robotics circulate in marketing materials. Independent, peer-reviewed research does support the underlying premise that laser weeding is a real, effective alternative to herbicides: a 2025 Cornell/Rutgers field study published in Pest Management Science found laser treatment reduced weed biomass by 97% or more in peas, beets and spinach, performed as well as or better than conventional herbicides including S-metolachlor, and caused far less crop damage (under 1% stunting versus a 34% head-weight reduction from S-metolachlor). That same peer-reviewed study cites a separate Western Growers industry case study reporting weeding costs falling from about $900/acre to roughly $269/acre on a large operation, a similar magnitude of savings to Kennedy's claim but with different numbers and a different farm. Laser-weeding units cost roughly $1-1.5 million, consistent with the payback-period framing Kennedy used elsewhere in the same conversation. Overall status: the general claim that laser weeding can substantially cut per-acre weed-control costs versus glyphosate and hand labor is well-supported by independent research, but Kennedy's specific onion-farmer figures are an unverified anecdote that could not be confirmed against any allowlisted primary source.