Spectracide Weed Stop for Lawns Ready to Use 1 Gallon controls more than 200 types of weeds as listed – and it won t harm your lawn when used as directed. This ready-to-use formula kills weeds down to the root with visible results in hours – weeds will begin wilting and browning overnight. It controls major broadleaf weeds including dandelion chickweed and clover and also kills poison ivy poison oak blackberry and kudzu (see product label for complete list). This product is rain fast in 6 hours so it won t wash off. This ready-to-use formula is ideal for spot treatments – requires no mixing. Some hard-to-kill weeds may require re-treatment. Wait at least 30 days between applications – some weeds can take that long to die. Spray just enough Spectracide Weed Stop for Lawns to lightly cover weeds – for best results apply when daytime temperatures are between 60 and 85 degrees. Do not apply when daytime temperatures are above 85 degrees as lawn injury can occur. Read the entire label before using.