Hormones as used by humans: This hormone is applied to leaf petiole cuttings by florists to stimulate adventitious root growth This hormone increases when seeds are moistened, initiating starch breakdown to simple sugar, which gives beer brewers a free step in their process This hormone finally wins out over auxin when Christmas tree farmers clip the tips of trees off to fatten them up This hormone drops it levels in seeds when light, temperature, and moisture conditions are set to be ideal by florists, prompting seeds to germinate Tomatoes are stimulated to ripen when exposed to this hormone