What can improper herbicide application lead to?

Improper herbicide application can lead to increased resistance issues in target weeds. When herbicides are misapplied—whether through incorrect timing, dosage, or method—it can cause stress on the weed populations. This stress can create selective pressure, allowing some individual weeds to survive and reproduce. Over time, these resistant individuals dominate the population, leading to a situation where herbicides become less effective or completely ineffective against certain weed species. This results in a cycle of escalating herbicide use, which contributes to further resistance and creates challenges for weed management in agricultural systems.

The other options don't accurately reflect the consequences of improper herbicide use. For example, higher crop prices are not a direct result of herbicide application issues, as market dynamics are influenced by numerous factors beyond weed control. Better soil moisture retention and enhanced crop shade are generally beneficial outcomes of proper agricultural practices but are not relevant to the effects of herbicide misapplication. Thus, the significant issue of increased resistance precisely highlights the challenges that arise from improper herbicide application.