Chemical Controls

Various herbicides are approved for treatment of invasive terrestrial species in New York State and, when used properly, can be an effective option for persistent or large-scale infestations of certain species. Types of herbicide and application regulations vary depending on target species, local regulations, and site considerations. As with all the management options discussed here, a mix of approaches customized to each site, user, and species will provide the most optimal results.

Infestations above a certain scale, growing near water or other environmentally sensitive habitats, or on steep slopes may be too costly or challenging to control via chemical application. In which case, other management options should be considered. Moreover, if chemical controls result in exposed soils, replanting sites with appropriate native vegetation will prevent a second wave of invasives from taking hold in low competition areas.

Benefits of chemical control:

• Will kill target plants
• Can exhibit residual control over seed-bank in future years depending on chemicals utilized
• Less labour intensive than alternative mechanical and cultural methods.

Limitations of chemical control:

• Should only be applied by licensed, trained, and experienced professionals following local regulations dictating physical and environmental safety
• Precautions need to be taken to limit the effects on surrounding non-target plants
• Limited use in environmentally sensitive areas or steep slopes
• May have limitations of certain soil conditions or in the proximity of water bodies
• Some concern from community groups

Selection of herbicide should depend on your target weed species, other crops or plants on site, environmental considerations, and meeting your management objectives.