Editor, RE: “New crop varieties ‘can’t keep up with global warming’” (The New Times, June 22). It is past time to stop at just COP-21; if you care about feeding your family, and humanity, you must recognize the following fact of agronomy: CO2 is a plant hormone antagonist. CO2 affects plants the way artificial steroids affect athletes, by making key growth hormones act more and cause body-wide changes. At natural levels, CO2 is good for plants. But we have not had natural levels of CO2 for over a century, and every year we get farther and farther into CO2 overdose range, the range greenhouse growers use on ornamental plants to make them bigger, or greenhouse growers who don’t care about their customers’ health use to make fruit bigger. In crops, CO2 makes ethylene and the gibberellins more active. This makes plants grow leggier and more massive, with less uptake of water. These sound like good things, but they are not. Plants that take up less water are more vulnerable to heat and to wind burn, two factors that happen more with global warming. Their roots generally go less deep, making them more vulnerable to flood erosion. As well, soil microbes are also stimulated nonselectively by CO2, so they take nutrients out of the soil, especially nitrogen, which they emit as NOx pollutants. But that’s what’s bad for the plants. For humans, it’s much worse. For centuries, farmers have bred the dwarf trait into plants that more of their vigor go to food production and less to chaff. CO2 reverses that work. Worse, CO2 causes plants to divert vigor from key protein building and mineral storage, leaving crops 6.5 per cent-15 per cent less nutrient dense. You can have more to eat, and still be eating worse, because of CO2 from fossil waste dumping. What to do: Privatize fossil waste disposal at a market price, with revenues paid to each citizen with lungs. If government won’t see this as much its duty as administering weights and measures, then do it yourself by telling those who sell to you that you only buy from those who have paid their CO2 debt by offsets. Indict those racketeers whose payments to obscure, perjure and lie about fossil waste liability to stakeholders are provable in court. If your government’s lawyers won’t do it, then get a class-action going. End subsidy to fossil, which the market might choose the winners, not the donors of elected officials. This one is tough, since it takes booting out of office those who are convinced they have the right to pick winners and losers on the market or be boosters for fossil. Bart R.