ChemFree+ contains natural compounds that inhibit the growth of a seed's tiny feeder roots, causing the weed or grass seedling to die before it ever has a chance to grow. Made of corn gluten meal, Chemfree+ is an all natural byproduct from the manufacture of corn starch. When used as directed, ChemFree+ is safe around people, pets, and wildlife; and it will not harm beneficial insects, soil organisms, ponds or stream life.