one of my customers has had a constant problem w. this viney weed. he calls it morning glory, not 100% if thats teh exact name. its around the house, and is growing like crazy under the deck, which gets very little sun. I sprayed it w. round up (under teh deck) around mid october and that seemed to work, for a week. what can i do to kill this weed. under the deck i am planning on putting down 3/4 inch decorative stone, id like to be able to put down a chemical to kill it. if there is anything to kill it, what process should i go through to get this area to bare dirt, or as close as possible? hit it w. the string timmer and then hopefully throw down whatever someone recomends. there is a lesco dealer near me. no i dont have a license, and i dont want to start a mess w. that. any input would be great, thanks!