Prodiamine or Dithiopyr for Preemergent Applications

Prodiamine and Dithiopyr are both preemergent herbicides that are used to prevent the growth of weeds before they emerge from the soil. However, they have some differences that may make one more suitable than the other depending on the specific circumstances.

Prodiamine is a selective herbicide that targets annual grasses and certain broadleaf weeds. It is typically used in turfgrass and ornamental settings, such as golf courses and landscape beds. Prodiamine works by inhibiting cell division in the roots of susceptible plants, which prevents them from growing and eventually causes their death. It is often applied in the early spring or fall before weed seeds germinate.

University of Tennessee Mobile Weed Manual

Dithiopyr is also a selective herbicide that targets annual grasses and broadleaf weeds. However, it has a broader spectrum of activity than Prodiamine and can also control some perennial weeds. Dithiopyr works by inhibiting cell division in both the roots and shoots of susceptible plants. It is typically used in turfgrass and ornamental settings and is often applied in the early spring or fall before weed seeds germinate.

One advantage of using Prodiamine is that it has a longer residual effect than Dithiopyr, meaning that it can provide weed control for a longer period of time after application. This can be beneficial in situations where there is a history of recurring weed problems. On the other hand, Dithiopyr has a faster rate of absorption and activity than Prodiamine, which can be beneficial in situations where there is a need for quick weed control.

Another factor to consider is the potential for phytotoxicity, which is the damage or injury that can occur to desirable plants as a result of herbicide application. Both Prodiamine and Dithiopyr have a low risk of phytotoxicity when used according to label directions, but Prodiamine is generally considered to be safer for use on a wider range of turfgrass and ornamental plants.

Overall, the choice between Prodiamine and Dithiopyr will depend on factors such as the target weeds, the desired length of residual control, and the potential for phytotoxicity. It is important to carefully read and follow label directions when using any herbicide to ensure effective and safe use.