Proposed Dates of Use: May 17th, 2024 – June 28th, 2024; as weather conditions and operational factors permit.
Street Address/Site Name: 28875 County Road 104, South Fork Preserve
Detailed Location of Application Site: Throughout the habitat and undeveloped areas. Site-specific postings will include details on exact location at time of application.
Posting and Notification: Site notifications will be posted at least 48 hours before application at site entrances and will remain posted for 24 hours, and via the pesticide application electronic notification system.
Product (W/ active ingredients): Telar – Chlorsulfuron (2-Chloro-N-[(4-methoxy-6-methyl1,3,5-triazin-2-yl)aminocarbonyl]) 75% EPA Reg #: 432-1561, CAS No. 64902-72-3 Pesticide Type: Herbicide City Use Type: Tier II. Less Hazardous. Less Restrictive.
Product (W/ active ingredients): Transline - Clopyralid: (3,6-dichloro-2-pyridinecarboxylic acid, monoethanolamine salt) 40.9% EPA Reg #: 62719-259, CAS No. 57754-85-5 Pesticide Type: Herbicide City Use Type: Tier II. Less Hazardous. Less Restrictive.
Product (W/ active ingredients): MSO Surfactant - Methylated vegetable oil, alcohol ethoxylate, phosphatidylcholine 100% EPA Reg #: CAS No. 97281-47-5, CAS No. 67784-80-9, CAS No. 34398-01-1 Pesticide Type: Adjuvant City Use Type: Tier II. Less Hazardous. Less Restrictive.
Target Pests: Short-pod mustard, black mustard, Italian thistle, yellow star thistle, milk thistle, fluellein, stinkwort, other broadleaf species as identified
Justification for Use: This use of herbicides is justified due to the size of the site, the size of infestation, and the growth stage of the existing weeds. The current infestation is largely a result of the size of the site and it's location to adjacent weed sources. These weeds can reduce the amount of grass cover or otherwise change the composition and structure of the habitat, reducing its value. Other weeds, including yellow star thistle, provide significant fuel for fire, burning hotter than grasses due to a high oil content. Currently, there are no reliable methods to control these weeds for the scale of this site using non-chemical methods.
Explanation of IPM Methods Use: Other acreage included within the open space management areas are maintained without pesticides. Areas that can be mowed or trimmed will receive those treatments, as needed to keep access clear and fire risk low. Staff will continue to do hand trimming, and pruning in areas not accessible to mowing equipment and re-incorporate grazing as a management tool for larger sites.
Strategies to Prevent Future Applications: The primary strategy to prevent future herbicide applications is to manage the native grasses to be the healthiest they can in order to resist and out-compete invasive plants. At suppressed levels, weed outbreaks can be reasonably controlled with hoeing or hand removal. Volunteers, interns and partner organizations will be leveraged to help with ongoing non-chemical control. Additionally, native wildflowers will be planted following the application to replace the invasive weeds with desirable forbs.
More information on the IPM Program, including the current Policies and Procedures guidance, can be found on the City's webpage: Integrated Pest Management
