Mixing a batch of herbicides together can be trickier than it sounds.
There are several universal goals that need to be achieved when making an herbicide application. They are:
- Using compatible materials
- Using chemicals that are safe for the areas of application
- Using a mix that will achieve the desired vegetation management results
- Creating the right quantity of mix
First the herbicide mix must be safe to create and safe to apply. There are many herbicides that are incompatible with each other and will cause an undesired chemical reaction when they are mixed. Others need to be mixed in a specific order to avoid bad reactions. Example of chemical reactions are a gelling of the herbicide mix, excessive foaming, or the creation of noxious gasses.
Second, the mix must be safe to apply in the area where the vegetation problem exists. For example, if there is running water or even standing water, only certain herbicides can be used in these areas. Also, some herbicides are highly volatile and can evaporate very quickly in hotter temperatures. If this happens the application will be ineffective and neighboring plants could be damaged.
Third, the mix must achieve a desired results and be effective on the target plants. While non-selective herbicides like glyphosate will kill many plants there are still many species that it will not kill. Often a mix of chemicals, both non-selective and selective, must be mixed together to accomplish the goals of the treatment. Typically a surfactant must be added to boost the herbicides ability to work properly. Some herbicides need a surfactant to help them penetrate the leaf’s surface or decrease surface tension so they can make better contact with the leaf. The cleanliness and the pH of the water used to make the mix are important as well. Highly acidic water or water with a lot of dirt in it will both cause herbicides to lose their effectiveness. Finally, pre-emergent’s are needed if new vegetation growth is not desired, otherwise the site will have to be sprayed monthly to control the vegetation.
Last, the mix has to be large enough to do the entire job and small enough so there are not a lot of left over chemicals after the spray job is complete. Disposing of un-used herbicides in a safe and environmentally friendly way is very difficult. It is best to mix what you need and to use all of it on the site. Likewise over applying or under applying the mix can cause several problems, including environmental contamination and monetary loss.