Herbicides, or weed killers, come in many different formulas and types. Understanding the different types that are available, and how they work, will help you choose the right herbicide for your needs.

There are four main categories of herbicides: pre emergent, post emergent, selective, and non-selective.

• Pre Emergent Herbicides: These herbicides are applied before weeds are present to kill weed seeds underground, before they emerge. They must be applied at the right time, so they can work most effectively. They are applied in the spring (when temperatures reach 55 degrees) and again in the fall.
• Post Emergent Herbicides: Usually a liquid, these herbicides are applied to control weeds already present in your yard.
• Selective Herbicides: These products target specific types of weeds while leaving other plants unharmed, and are perfect when you want to control weeds that are growing close to or within desirable plants, like your lawn.
• Non-Selective Herbicides: Non-selective herbicides will kill all types of plants they come in contact with. Both weeds and desirable plants (like your lawn, ornamental plants, garden, etc.) will be damaged or killed by a non-selective herbicide, so they should be used in areas where no vegetation is desired, or used very carefully around desirable plants.