No-Till Soil Health and Weed Management Toolkit

Introduction

The UW Farm began in 2006 as a student-powered project growing vegetables behind the old Botany Greenhouse. Today, thanks to the power of their vision and the support of the CSF, the UW Farm cultivates about 2.5 acres of growing space with two full-time staff and three part-time student staff. With the introduction of the Food Systems, Nutrition, and Health major and the hard work of Farm Manager Perry Acworth, the UW Farm has expanded dramatically. This past year we hosted classes from across University departments, interacted with more than 500 students, and grew more vegetables than ever before. However, with this expansion we have felt a squeeze on our tool shed. Due to the inevitabilities of working with enthusiastic beginners some of our tools have been broken, while others we simply do not have enough of, leading to bottlenecks in production.

We would use this CSF grant to restock with high-quality tools designed to last, allowing the next generation of students to experience the efficiencies that small-scale farming has to offer. In addition to having enough tools, this grant would allow us to purchase the tools necessary for a no-till system. No-till systems are part of the so-called “brown revolution” in agriculture, which combines ancient ways of growing with new understandings of soil health (Montgomery 2017). Given the proper tools, we will be able to demonstrate a highly efficient system that produces healthier plants, sequesters carbon, saves water, and preserves soil health for the long haul.

Background

Tillage is the act of turning over or otherwise disturbing the soil, and has been practiced by farmers for thousands of years. Tillage helps introduce oxygen into the earth, stimulating the activity of soil microbes and encouraging the breakdown of organic matter into plant soluble nutrients. This is a boon for farmers, who appreciate the burst of fertility that tillage gives to their soil. Tillage can also be used to incorporate crop or weed residue into the soil, creating a clean planting surface.

However, scientists and farmers are beginning to realize that long-term tillage can destroy the productivity and health of soil. Soil is made up of rock particles held together by an incredibly diverse ecosystem of organisms. Plants interact with these systems by emitting exudates through their roots to feed beneficial microbial communities. Organisms in the soil can fix nitrogen from the atmosphere, emit growth-promoting plant hormones, scavenge micronutrients from mineral deposits, and much more. While we are far from understanding the processes behind these feats, one thing is clear: tillage destroys soil life. Soil disturbance kills earthworms, shreds fungi, and pulverizes the aggregates that create soil habitat.

The effect of tillage on soil intersects with a number of crucial environmental and social problems relating to the sustainability of human agriculture. Long-term use of tillage can cause a precipitous decline in the amount of organic carbon stored in the soil, which is then released into the atmosphere. It is estimated that by the time of the Industrial Revolution, humans had already contributed one-third of our total greenhouse gas emissions simply by tilling the soil (Lal 2004). Soils with less organic matter absorb less water, contributing to poor crop performance in droughts and leading to increased erosion. Plants in unhealthy soils require more chemical fertilizer and more pesticides to resist predators. Tillage also brings new weed seeds to the surface with every pass, creating a vicious cycle of more cultivation and more work (Montgomery 2017).

While the UW Farm currently operates on a low-tillage system, having the right tools would allow us to engage students more effectively in different models of sustainable agriculture. Every item in our budget fits into our system in a specific way to promote soil health, sequester carbon, grow better crops, and make our labor more efficient. In our letter of intent, we will focus on three specific items and how they fit into our system: the broadfork, the flame weeder, and compost.

Broadforks are the most important garden bed preparation tool for any no-till grower of our scale (Fortier 2014). They allow us to aerate and loosen the soil without disturbing soil life. They also will reduce weed pressure, because they do not invert the soil and bring buried weed seeds to the surface.

In order to further reduce the amount of soil disturbance from weeding, we propose to purchase two different models of flame weeder, one for each of our sites. Flame weeding uses a gas torch to kill weeds when they are just beginning to germinate. This technique can be used to quickly create weed-free beds without cultivation of the soil, allowing us more time to focus on other farm systems while also improving soil health. While it may seem counterintuitive to burn fossil fuels to kill weeds on a sustainable farm, the flame weeders in our budget actually use very little natural gas due to their efficient design, and they are a long-term investment in reducing the weed seed bank present in our soil.

One of the largest expenditures in the budget is for sixty yards of compost. No-till systems generally apply layers of compost that are several inches thick in order to boost soil organic matter and suppress weeds. We currently have access to compost made from UW leaves and coffee grounds, but that is only available in the fall and contains plastic and other litter. A large quantity of high-quality compost from Cedar Grove would be an important investment in soil health for the UW Farm.

Conclusion

No-till agriculture is one of the world’s best chances to reduce carbon emissions from agriculture and improve soil health. We plan on using both qualitative crop evaluation and quantitative means, such as soil testing, to evaluate our practices. We thank you for your consideration for this grant, which would allow the UW Farm to practice and teach the future of agriculture.

Stakeholders

Aisling Doyle-Wade, Lead Student Staff
Duke Clinch, Student Staff
Reily Savenetti, Student Staff
Adam Houston, Assistant Farm Manager
Perry Acworth, Farm Manager
Eli Wheat, Lecturer, Program on the Environment

Works Cited

Fortier, Jean-Martin, and Marie Bilodeau. The Market Gardener: A Successful Grower's Handbook for Small-scale Organic Farming. New Society Publishers, 2014.

Lal, Rattan. "Soil carbon sequestration impacts on global climate change and food security." science 304.5677 (2004): 1623-1627.

Montgomery, David R. Growing a revolution: bringing our soil back to life. WW Norton & Company, 2017.

Draft Budget

No-Till Soil Health Management

Weed Management

Timeline

Winter 2020 - purchase and assemble tools

March 2020 - begin soil testing with UW Soil Science class

Spring, Summer, and Fall 2020 - use tools during growing season

November 2020 - autumn soil testing to evaluate progress