Posted on July 19, 2023 by SF Forest Alliance (SFForest.org)
We’ve just finished our annual compilation and analysis of the pesticide usage data for San Francisco Recreation and Parks Department for 2022.
Overall, San Francisco Recreation and Parks Department (SFRPD) herbicide usage was similar to that in 2021. However, it is interesting to break out the amounts used by the single largest herbicide user, the Natural Resources Division (NRD), and what we describe as SFRPD Other – that is, all the other divisions put together.
After very sharply lowering pesticide usage in 2021, SFRPD Other has increased usage again. This is mainly from the use of burndown herbicide Axxe around the perimeter of artificial turf on playing fields. Still, it has not returned to the extremes of 2019 and 2020. It also used less of most other pesticides.
WHAT ABOUT THE NATURAL RESOURCES DIVISION (NRD)?
The Natural Resources Department (NRD, formerly the Natural Areas Program or NAP) is the entity that in trying to bring “native” plants to more than a thousand acres of our parks, cuts down trees and restrict access to people and their pets. It’s a major user of toxic herbicides.
The good news is that after two years of sharply increased herbicide use in 2020 and 2021, the NRD has reduced its usage. It’s not yet down to the recent low in 2016.
It still exceeds the total usage by all other SFRPD divisions combined. The picture below shows the same graphs side by side: The first is herbicide use by all of SFRPD excluding NRD; and the second is NRD herbicide us. Except in 2019, NRD’s pesticide use was higher than all the rest of SFRPD in every year since 2016.
NRD, which accounts for perhaps a quarter of the land area, still accounted for over 2/3 of SFRPD’s total herbicide use in 2022. (In 2021, it went as high as 90% because other divisions had curtailed herbicide applications very sharply – but NRD increased their use.)
It also uses more toxic chemicals, including glyphosate (best known as the active ingredient of Roundup) and triclopyr (used in Garlon and Vastlan). The rest of SFRPD has not used either of these herbicides in recent years.
SHARP PARK PESTICIDES
The usual discourse around golf courses is that they are drenched in strong pesticides, while Natural areas are free of these toxins. And this may be true sometimes – including perhaps Harding Park, which we exclude from our analysis for reasons explained below. It’s not true of other golf courses in San Francisco, which seldom use herbicides at all. In the past, it’ s been particularly untrue of Sharp Park. For many years, Sharp Park was off-limits for pesticides, with extremely minimal localized use. It’s home to the endangered red-legged frog and San Francisco garter snake.
The bad news is that in 2021, that changed. We did foresee it, as NRD was extending its hold on the park. So it was not unexpected, but it was sudden. In the space of one year, pesticides were applied 9 times. It got worse in 2022: pesticides were applied 13 times. We hope the red-legged frog and the San Francisco garter snake are fond of Clearcast, Polaris, and Milestone.
EXPANDING THE FUTILE HIT LIST
Thus far, NRD has a list of some 57 target species of plants that it tries to fight. (This list is derived from many years of pesticide usage reports, which specify the “pest” targeted with each application.) For obvious reasons, herbicide use against that number of “invasive” species is futile.
Theoretically, the point of using toxic herbicides on unwanted species is to allow the preferred species to replace them. Instead, the continued usage of these chemicals shows that if anything, the situation is only made worse. “Invasive” plants are successful because they are better adapted to current conditions. If they are destroyed with herbicides, the replacement is likely to be the next best adapted (thus, invasive) species. Given 57 target species, the bench is deep.
TIER HAZARD RATINGS
San Francisco’s Department of the Environment (SFEnvironment) assigns Tier hazard ratings to the various pesticides it uses. Tier III is Least Hazardous, Tier II is More Hazardous, and Tier I is Most Hazardous. Over the years we have been following this usage, we have seen various chemicals being moved from one Tier to another. Milestone was moved from Tier I to Tier II; Glyphosate (Roundup, Aquamaster) from Tier II to Tier I; and triclopyr (Garlon, Garlon 4 Ultra, Turflon, Vastlan) from Tier I to Tier II (for Vastlan and Turflon). Avenger was moved from Tier II to Tier III, which we think makes sense and makes analysis easier. We analyze the usage of Tier I and Tier II herbicides.
SF Environment publishes, each year, a Reduced Risk Pesticide list that includes the Tier rating of all chemicals approved for use on city-owned property. Here is the list for 2022: 2022_sf_reduced_risk_pesticide_list
It can also be downloaded from their website, SFEnvironment.org at this link: 2022_sf_reduced_risk_pesticide_list
OUR METHODOLOGY
Our data are compiled from the monthly pesticide usage reports produced by the various departments of SFRPD.
We exclude Harding Park – but not the other golf courses – from this analysis because it’s externally-managed under a PGA contract to be kept tournament-ready at all times. We do not include adjuvants like Competitor, which are used to dilute the pesticide and make it more effective, but are not active in themselves. We also exclude the herbicide Greenmatch, which is organic even though SF Environment classifies it as Tier II.
After compiling the data into our database, we derive the amount of active ingredient (in fluid ounces), using the manufacturer’s formula. These data are currently the basis for all our published comparisons.
REDUCE OR ELIMINATE HERBICIDE USE
We end this article with our usual plea. SF Forest Alliance has been trying to encourage SFRPD to reduce or eliminate Tier I and Tier II herbicide use. Back in 2016, it appeared that pesticide usage was declining, especially after the Roundup revelations. When we wrote our Pesticides report for 2016, the other areas of SFRPD had slashed their herbicide use; the NRD accounted for 74% of pesticide usage. We hope the 2022 data indicate a move in the right direction.
Pesticide notice – Amber Street Entrance at base of stairs – Jan 30 2023
