Pre-emergent Herbicide: these herbicides are applied to soil as granules or liquids. They may be mixed with fertilizers and packaged together.

• Pre-emegents are used before weed seeds germinate. Read the label for the proper timing to target your specific weed.
• When watered in correctly, pre-emergent herbicides create a barrier or a blanket across the ground that does not allow seeds below it to germinate.
• This includes desirable grass seeds. Pre-emergents cannot be used when seeding, with the exception of siduron.
• Once the barrier has been created, be careful not to disturbed the soil or you will create holes in the barrier.

Post-emergent herbicide: these herbicides are applied after the weeds have emerged, and most require good contact with the leaf.

• Some kill only broad leaf weeds. Some kill only sedges. Some kill only grass or grass like weeds.
• Not all herbicides kill the specific weed you’re going for.
• Know what weed you have, and look up the proper herbicide to use.
• Timing is critical. Read the herbicide label to know when to apply the product according to the specific weed you are targeting.
• For example: crabgrass must be sprayed before the second leaf comes out. Nutsedge should be sprayed when there are three to eight leaves present.
• Some herbicides will injure some types of turf. READ THE LABEL before applying.

Broad spectrum herbicide: Kills or prevents a wide range of plant species.

• For example: Glyphosate (Round up) will kill all vegetation that it comes in contact with.
• Non-ionic Surfactant: Also sometimes  referred to as a spreader sticker. This is a liquid product that you mix into the tank along with your herbicide. Surfactants improve leaf coverage and increase efficiency of the herbicide. Some herbicides come with surfactants pre-mixed in them. Read the label to see if the herbicide you are using needs a surfactant.
• Translocation: The movement of herbicide from one part of the plant to another. For example, an herbicide may be spayed on to the leaves of a plant, then move within the plant to the roots.