11. I have tried broadleaf weedkillers to no avail. 12. The soybean seeds are sold by Monsanto for use with its popular Roundup weedkiller . 13. Those varieties can be sprayed with a weedkiller that will kill the StarLink plants. 14. It is a component of many common weedkillers . 15. The biotech soy is immune to the Monsanto Co .'s popular Roundup weedkiller . 16. In May 2009 some one had sprayed six phallic shapes into the grass with weedkiller . 17. Burning pampas grass does not always kill it at the roots, but chemical weedkiller does. 18. He could use the ever popular weedkiller ( potassium chlorate or sodium chlorate ) and sugar. 19. Penetrants are most often used against plants that would otherwise be able to resist the weedkiller . 20. The company used to mainly make weedkillers and insecticides, but has shifted its focus to pharmaceuticals.