NOTE: 4 oz and 16 oz sizes are repackaged in bags that are sold without labels. Please download the instructions from the PDF on this webpage for application information and other instructions. Gnatrol is a highly selective, biological larvicide for use in greenhouses to control fungus gnat larvae. It may be used on a wide variety of ornamentals, as well as all bulb crops, bedding plants and vegetable sets. Once the larvae have ingested Gnatrol, they become paralyzed, stop feeding immediately and die—usually within 24 hours. Gnatrol is now available in a water dispersible granule (WDG) formulation that will not leave a residue and is easier to measure for increased application accuracy. For Ornamental and nursery plantings in greenhouses or potting soil mixtures and for Vegetable plants such as Tomatoes, leafy and cole crops, cucumbers, peppers and eggplants. Suggested rates are: for light infestation: 3.2 to 6.4 oz/100 gallons applied as a soil drench. For heavy infestation: 13 to 26 oz/100 gallons applied as a soil drench. For best results, apply drenches toward the end of irrigation period. GnatrolWDG is a larvicide and will not control adult gnats, therefore, applications must be timed for a stage of development when larvae are present in the soil. Fungus gnat larvae generally respond to GnatrolWDG treatment within 24 hours following application.