Green Measures Have Consequences Under France’s new Climate and Resilience law, farmers must reduce their emissions from nitrogen fertilizer by 15 percent or eventually face a fine for not doing so. In addition, school and government cafeterias must offer a vegetarian option at least once a week, and the law requires preserving France’s food sovereignty. The good news is that France will still probably be able to feed itself, but its famed exports may take a hit from the resulting fall in production.  Nitrogen is the most deficient nutrient in most plants and in crops like wheat, it enables photosynthesis to occur. One analysis calculates the correlation between nitrogen use and wheat yield at 99 percent. This means a 15...