Toxins and poisons do not pick and choose who and what they maim or kill. 2 4-D is one vicious, wide-swath killer of everything with which it contacts. My former neighbor used it to kill his lawn so he could reseed it without any regard for the deleterious affects on birds, worms, soil inhabitants, or water runoff. The EPA is yet another sellout depending on what area/department within the agency issues the permits for such poisons. Dow and Monsanto seem to be their best pets for issuing permits for proven toxins and poisons over the last few decades. The FDA is just as culpable. I cannot eat soy due to an autoimmune disorder nor do I consume any vegetables/fruits that are not locally and organically grown. Cost may be higher but not nearly as high as the cost of medical care for ingesting poisoned food (GMO, sprayed, injected, or otherwise chemically treated/altered).
The bees have been decimated, I haven't seen a dragon fly or a butterfly like I used to see everywhere, our state sprays roadsides totally mindlessly year after year, no amount of letter writing, calling or posting flyers seem to have helped much, so I am open to ideas but think direct massive action is needed to ban roundup and all other deadly chemical agents outright.
2,4 D does not kill lawns. It only kills weeds. Your neighbor was probably using something else.
BTW, your neighbor has a problem if he keeps killing and reseeding his lawn every year.
It also kills fruit trees, tomato plants, squash plants indiscriminately...even when the owners thereof do not use the poison...death comes from drift and run off. Lawns treated with 2,4 d also have a history of causing numerous cancers among dogs that may ingest the grass or sniff it (nasal carcinomas). My neighbor must have used the 2,4 d in combination with other chemicals in one bag because whatever the application contained, it killed everything. To my knowledge, he has only done this once in the last four years...one damn time too many.