...little earlier. Unless your entire lawn has been infested with crabgrass, consider applying the chemical only in those areas where you have had a crabgrass problem. There is no need to use excess chemical by treating the entire yard.

...gene called MAO-A (monoamine oxidase). The gene's assigned task is to make an enzyme that clears the brain of excess chemicals called neuro-transmitters, such as norepinephrine and dopamine. If these chemicals aren't disposed of fast...