Roundup is a weed killer that allows you to target specific plants by selectively spraying them. Roundup kills almost any plant it comes in contact with, but becomes inert in the soil as long as you don’t saturate it. The downside is that it takes a couple of weeks for the weeds to die after you use Roundup.
Prepare to spray. Wear safety glasses, gloves and a filter mask or bandanna over your mouth and nose. Wait for a day when the wind is calm and rain is not expected for several hours. Read the Roundup label thoroughly and completely.
Position the sprayer a few inches from the undesired plant and spray lightly. It is not necessary to saturate the plant with Roundup. One or two good sprays should do it.
For application when wind is present, wet a sponge with Roundup liquid and daub it on the leaves of the plant. Wear latex or rubber gloves when using this application method.
For zeroing in and targeting a specific plant, use a funnel made from an empty 2-liter soda bottle. Cut off the bottom of the bottle. Slip the bottle over the plant you want to spray and spray Roundup through the open bottle top.
Wait for two weeks. If the plants show no signs of turning brown and/or wilting, spray again with Roundup.