Round Up: Aren’t You Glad Companies That Made WMD’s Also Produce Weed Killer? With spring gardening and landscaping in full swing, it’s sometimes tempting to use harsh chemicals to control those pesky weeds. One of the most popular of those weed killers is Monsanto’s Round Up. This awesome cartoon from the talented Joe Mohr (also seen on Twilight Earth and Wend Magazine) might help you think twice before deploying Round Up in your fight against weeds. About JeffreyYo. I'm Jeffrey. I think every little step is an awesome one when it comes to living green... but eco-snobbery sucks.