The effectiveness of herbicide applications are dependent upon three things: 1) selection of the correct herbicides, 2) timeliness of application, and 3) mother nature. We can control the first two.
Using one of the best herbicide mixtures on the market has allowed us to achieve a standard of less than 10% re-spray during the growing season. However, weeds become resistant to the same herbicides applied year after year so each year we evaluate our mix and adjust it slightly.
Over the past few years new herbicides have increased effectiveness as well as reduced the risks of run-off. These lower use rate herbicides add considerable value.