On 21 Dec 2013, at 17:34, Robin Hansen quoted Diane Whitehead: > "The only fungicide I use is powdered sulphur. I take a pinch between thumb and > finger and slide them together so it dusts down." > > > So, Diane, sulfur used the way you use it (with gloves? without gloves, mask, > etc.?) is non-toxic to humans? Sulfur is fine. It is, in fact, an essential nutrient. Speaking as a trained chemist. It endlessly annoys me that the hysterics these days run around "it's a chemical, it's a chemical" or "it's poisonous, it's poisonous" with no sense of understanding or nuance and end up frightened by things that can't harm you or won't harm you much. Chemicals: almost everything is a chemical: water, salt, and sugar, for example. Atmospheric oxygen, too. If you work a little harder you can say "it's a synthetic, petrochemical-derived pesticide with a high mammalian LD50, no thanks" and then you'll be much closer to a reasonable attitude. Insecticides were chosen for marketing partly on the grounds that they had a high LD50 for insects relative to their LD50 for mammals, and the ratios of the two LD50 figures is sometimes quite astonishing. That said, I'd still be cautious with the old classic pesticides: captan, benomyl, methoxychlor, diazinon, and malathion. (Many of these are now verboten in many places.) By way of contrast, Sevin (carbaryl), a cholinesterase inhibitor, has such low mammalian toxicity that it can be used as a flea powder on cats. Makes them drool a little, but that's all. It is extremely toxic to hymenopterous insects (bees, ants, wasps) so it's good for dusting hornet nests, but very bad used on flowering plants where bees are foraging. But *reasonable* care is always a good idea. I wouldn't use any of these synthetic, petrochemical-derived insecticides without putting on gloves. The pale blue nitrile rubber gloves used by mechanics are good (and won't cause latex sensitivity), so make sure your gardening supplies include a box. I don't know enough about the much more modern neonicotinoid insecticides to pontificate on them, but they have been implicated in bee colony deaths. I only use them on my cats on the rare occasions they get fleas. As for "poisonous! poisonous! quick, run, hide, everyone", the difficulty is lack of nuance. There are some plants you're crazy to grow; the director of Kew Gardens, for example, wouldn't have Aconitum ferox in his garden. It's extremely poisonous — lethal, in fact — and can kill you. (If you grow root crops, do NOT grow any aconitum species: people have died from thinking their tubers are Jerusalem artichokes.) On the other, those lists of "100 common poisonous garden plants" you see in magazines and newspapers (what are those? says the e-generation) are too tainted by modern journalism's love of sensationalism to be trusted. Yes, daffodils are in some sense poisonous, but I suspect that all you get is diarrhea and an upset stomach. And of course, if you have a yard ape or rug rat on the premises who tends to mouth anything he or she sees, daphnes are probably a bad idea: their berries (many bright red) may attract said yard ape's (or rug rat's) attention. Nuance, people, nuance. Don't think in broad categories or you'll end up cowering in fear in a basement corner. But also don't be a fool and think "everything is quite innocuous". End of today's Sunday sermon. Send money. -- Rodger Whitlock Victoria, British Columbia, Canada Z. 7-8, cool Mediterranean climate