Mackenzie Feldman co-founded then-Herbicide-Free Cal with teammate and comrade, Bridget Gustafson. They got involved in the issue of herbicides when they showed up for Cal’s Beach Volleyball practice and their coach cautioned them not to chase after the balls if they roll off the court, because the groundskeepers had just sprayed an herbicide on the surrounding area. 

Bridget and Mackenzie were shocked. They knew they had to find out what was sprayed and put an end to it. They set up a meeting with the Supervisor of Athletics Fields & Turf, and found out that the chemical sprayed was Ranger Pro, which contains the same amount of glyphosate as Roundup.

This was two years before the Johnson v. Monsanto ruling, but one year after the World Health Organization had ruled that glyphosate was a probable human carcinogen. They asked him not to spray anymore, and in return, the team would pick the weeds that would grow back. 

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Since that day, Bridget and Mackenzie have made lasting, institutional change. After the success of banning herbicides from the Clark Kerr Campus Beach Volleyball courts at UC Berkeley, the focus was moved to the entire campus, and Bridget and Mackenzie got the ASUC student government involved in creating an official Herbicide-Free Cal student campaign team. The team accomplished many tasks, from designing a logo to policy writing in order to institutionalize the campaign.

After several meetings with the Grounds Manager to understand what the needs were to transition the campus, Bridget and Mackenzie organized several 6-hour work days where they got various student groups to mulch the soil in order to suffocate the weeds. Professors gave extra credit to students for volunteering.


Mackenzie and Bridget went on to secure a grant to get support from Beyond Pesticides, a national organization that helps communities transition away from toxic pesticides. First up: highly trafficked places like UC Berkeley’s popular Memorial Glade and Faculty Glade. Beyond Pesticides’ board member, Chip Osborne, a professional horticulturist, was brought in to teach UC groundskeepers how to enhance soil biology in order to prevent weeds from growing. 

Now, in addition to the beach courts, pesticides and herbicides have been discontinued from Memorial Glade, Faculty Glade, and seven other spaces at UC Berkeley, and Herbicide-Free Campus is currently working with the Grounds Manager at Berkeley to eventually make the entire UC Berkeley campus herbicide-free. Mackenzie and Bridget have had countless organizations, professors, students, and even the UC Berkeley Chancellor champion their efforts and offer support. 

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Upon graduation, Mackenzie launched Herbicide-Free UC, and now Herbicide-Free Campus, to inspire the entire UC system to rethink its reliance on toxic herbicides in grounds management. The campaign now exists at UC Riverside, UC Davis, UCLA, and UC Santa Barbara, and the work of the Herbicide-Free UC fellows at these campuses has resulted in UC President Janet Napolitano temporarily banning glyphosate on all 10 campuses. We are currently working with the University of California Office of the President to make the glyphosate ban permanent as well as transition away from all toxic herbicides, and helping to train the groundskeepers on how to transition to organic methods. Now, the campaign has expanded nationally with the goal of eliminating toxic herbicides from every school in the country.



For Mackenzie, this seemingly small battle represents a larger issue at hand; one of the most consequential environmental issues of our time. Conventional agriculture uses an abundance of pesticides and herbicides, which are depleting the earth’s natural resources and immensely harming human health.

Mackenzie's home state of Hawaii, where less than two centuries ago, native Hawaiians fed their communities using some of the most historically sustainable agricultural practices ever documented, has recently become “ground zero” for industrial agriculture, and around 90 percent of Hawaii's food is imported.

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Hawaii is now the world’s leading producer of genetically engineered seed corn, which has resulted in an immense amount of spraying. Hawaii now use 17 times more restricted-use insecticides per acre than on the U.S. mainland. Monsanto, Pioneer, Dow AgroSciences and Syngenta have established research stations on four of our eight islands. These research stations are located near the homes of Native Hawaiians of the lowest socioeconomic bracket, resulting in their disproportionate exposure to herbicides. Children who attend school near these testing sites have begun to be frequently sent home sick. These communities have become “cancer clusters”, and Hawaii now has 10 times the national rate of birth defects and illnesses. 

Mackenzie's Hawaiian roots fuel her passion every day to want to spread awareness around herbicides. This issue hits close to home - literally - and is a constant reminder of what inspired her to join the movement in the first place.