A dire drought that has plagued Texas and parts of Oklahoma expanded across the key farming state of Kansas over the last week, adding to struggles of wheat farmers already dealing with weather-ravaged fields. Harvest in Kansas, the top U.S. wheat-growing state, is set to begin within weeks. But a report issued Thursday by a…

Critics say it’s a chemical that could cause infertility or cancer, while others see it speeding the growth of super weeds and causing worrying changes to plants and soil. Backers say it is safe and has made a big contribution to food production. It’s glyphosate, the key – but controversial – ingredient in Roundup herbicide…