My interpretation of what is given in Yahoo Answers is that people who keep their heads down (the shorter trees) experience less conflict than those who draw attention (the taller trees that catch the wind, or in a slightly different version, catch much wind.) The person mentioning the expression gave the impression they were alerting me that I should be prepared for criticism of my book about Rocky Flats and my contention in the blog that the wildlife refuge surrounding the former plant location would be safe to visit with my family.