Strategies to Improve the Efficacy of Applications
With the 2020 growing season behind us, let’s take some time to reflect on what we learned and what to look forward to for the 2021 season. 2020 definitely had us all thinking outside the box. From the way that we conduct our normal daily routines, to figuring out how to work and run your business safely, to a very different than normal Virginia weather pattern. We have all had our share of problems, hardships, success, and memories. Some good, some bad, but whatever they were, we should all have taken something away from them and learned from our experiences.
Looking forward to 2021 may pose more questions again than answers. Will we continue with the status quo? Will we go back to the way we did things before? What will the weather be like? What did we change that worked? What didn’t? One thing we know is, for the most part, our lawn applications will remain the same right? Or will they?
Spring in Virginia can be like a box of chocolates. However, getting a pre-emergent down at the right time is still imperative; moreover, choosing the right fertilizer, pre-emergent, soil amendment combination is also paramount. Typically you have the choice of pre-emergents like Dimension (Dithiopyr) or Barricade (Prodiamine). These products don’t allow the germination of label-listed weeds and grasses in turf. These can either be applied in a liquid tank mix application or impregnated on granular fertilizer.
How you apply depends on your operation and budget. Whichever way they are applied, and whichever product you use, your rates, nitrogen, phosphorus, potassium, (NPK) micros, and other additives inputs can play a part in response, longevity, efficacy, and when tank mixing, sometimes gumming and clogging.
When using an impregnated fertilizer, make sure the active ingredient load rate will be in conjunction with the NPK rates to get enough active down per application or to not go off max label rate or Virginia’s fertilizer laws. Other things to consider are the number of applications you are going to make, the rates at which the active will be applied, the longevity of that active’s effectiveness, and your desired results.
Weather can also play a huge role in any product’s efficacy. One other idea to consider would be to apply a pre-emergent with or without fertilizer (weather dependant) late in fall. This will give you some control over those unsightly spring weeds that typically emerge before the first application. Just be aware of the total AI label application rate in a calendar year.
Another option that has been on the market for a few years now is Tenacity (Mesotrione). This product gives you the ability to have pre-emergent and post-emergent coverage with the ability to still plant fescue seed. It’s one drawback is it turns the grass white (bleaching) for a short time. It is still recommended that all cool-season grass be sown in the fall. However, if seeding in the spring is inevitable, it can be used. If this is the case, although not recommended, I suggest following the research of Virginia Tech’s Dr. Adam Nichols and Dr. Jeff Derr at HRAREC a few years ago on tall fescue with Mesotrione and fungicides applications.
If those early spring weeds do show their ugly follagie, choosing the right post-emergent can also be key. Early in the spring while temperatures are down, getting herbicides to move through a plant can prove troublesome if the right formulation is not used. Although there are many choices for cold weather post-emergent herbicides, which one will work best for you? Typically most herbicides with an ester-based formulation will perform well in colder weather. Nevertheless, it’s still not a one size fits all. This will also depend on targeted weeds (labeled weeds), rates, budget, and applications.
No matter what 2021 brings us, remember what 2020 has taught us. We’ll need to continuously adapt, change, and prosper. Just like the weather and circumstances beyond our control, the key to a healthy lawn is ever-changing. Pesticide resistance is real and should not be ignored. Product rotation is key to not having immune species and diseases. Maybe your program isn’t getting you the desired results? What if you’ve been doing the same thing for the last six years? Whatever the case may be, sometimes a little change can go a long way.