This month we have explored issues that relate our plate to the health of the ocean. By making choices about what goes onto your plate, you are making choices that affect the earth—and this choice is not limited to what type of seafood you eat. Even the vegetables and meat grown on land are connected to the ocean. This week our partners in education at Hidden Villa explain the connection between farms and the ocean.
“The San Francisco Bay watershed covers 75,000 square miles. A watershed is simply a geographic area defined by the flow of water. No matter where you live, even if you can’t see where it goes, the rain that falls on your lawn drains into a river or lake and eventually the ocean. All of the water that falls within a watershed flows to a common place. In our case, it is the dynamic San Francisco Bay, home to copious species of marine life. According to the Environmental Protection Agency (EPA), water quality in the Bay has been steadily declining. This trend is also seen throughout the watershed, problematic for the 25 million Californians receiving their drinking water from the watershed as well as the 7000 acres of farmland found here. Land-usage is directly linked to water quality. In general, samples from upstream locations are cleaner than those taken downstream. Samples from urban areas also show more contamination than more undeveloped areas. For a more detailed analysis of this topic, check out the following link.
In fact, the amount of agriculture found in this fertile region of the country is linked to at least some of the water quality problems found in the Bay. In large-scale conventional farming, pesticides and herbicides are applied to crops to increase yields. Once applied to the plants, only a small amount of the chemicals stay on the plants. Based on the chemical makeup of both the chemicals and the soil, some remains in the soil, but most end up flowing downstream in the watershed. And where do these chemicals ultimately end up? You guessed it. In San FranciscoBay!
Everything that happens upstream affects water quality downstream. In addition to contributing chemicals to the watershed, many farming techniques also increase the amount of sediment that is present in waters. This happens when fields are left empty, or fallow, for a period of time. Compared to natural areas with native plant populations or cropped fields, fallow fields have no roots present holding down the soil, making them far more susceptible to erosion by both wind and water. The increased sediment in waters is problematic for many reasons.
First, it decreases water flow through stream and river bottoms. This decreases the amount of oxygen available to invertebrate populations living there. Higher sediment levels also clog the gills of fish, inhibiting their ability to breathe. In addition, waters with more sediment absorb more sunlight, warming the water. This can be extremely detrimental to fish and invertebrate populations who have narrow optimal temperature ranges. Harmful chemicals lingering from past activities such as mining are also added to the waterways by way of erosion.
Water quality problems are often difficult to diagnose and treat because they originate all over the watershed. The following link gives a breakdown of creeks with impaired water quality in the San Francisco Bay area. It is from 2002, so it’s not the most up-to-date analysis, but I’m including it here as a good resource for those interested in further researching exactly what chemicals are polluting our local waters as well as their sources.
The link below shows a map with streams listed as impaired in 2010. It also allows you to filter by region, pollutant, and pollutant category.
In contrast to conventional agriculture, which is heavily reliant on the use of chemicals to produce food, organic agriculture does not use synthetic chemicals. Instead, organic farmers use other techniques to manage pest and weed problems. To describe some of these techniques employed by organic farmers, I will use my farm, Hidden Villa, as a case study.
Hidden Villa is a non-profit, organic educational farm located in Los Altos Hills. Open to the public and frequently visited by school groups, this farm has a long legacy of educating adults and children alike about food production and social justice. In addition to its educational programs, Hidden Villa has about 40 acres in agricultural and meat production. If you’re interested in learning more about the farm and the programs available, check out the website:
At mid-scale organic farms like Hidden Villa, actively building healthy soil is a critical part of regulating pests without the use of synthetic pesticides. Healthy soils are alive! They are teaming with communities of diverse insects, which, in addition to building fertile soils, naturally keep each other’s populations in check. Some of these insects also prey upon harmful insects that would otherwise eat the crops. Composting turns unwanted food scraps, animal manure, and other organic material such as corn stalks back into fertile soil. In addition to containing lots of bug life, this soil is full of the nutrients plants need, and reducing the need for additional fertilizers to enhance plant growth.
Rotational cropping and cover cropping are two more techniques employed to increase soil fertility. Different crops have different nutrient needs, depleting the soils of different nutrients at different rates. By planting crops in a specific rotation, the farmer can help avoid depletion of specific nutrients. With cover cropping, the fields are not left fallow, but rather planted with a crop that adds a nutrient, such as nitrogen to the soil. In addition to helping build soil fertility, this also decreases the previously discussed erosion problems associated with fallow fields. One more way our farm protects the ocean is through drip-irrigation, which conserves water much better than sprinkling. By watering directly at the roots we don’t waste excess H2O or create more runoff leading to erosion.
Crop diversity is another key part of an organic farmer’s toolbox. In contrast to the mono-crop model of large-scale farms (either conventional or organic) where a single crop is grown for market, small to mid-scale organic farms typically produce many varieties of fruits and vegetables. For example, Hidden Villa produces tomatoes, carrots, kale, lettuce, potatoes, and peppers, to name just a few. In addition, rather than having a single variety of tomato or pepper, there are many varieties present. This amount of genetic diversity protects the crops from pests. Diversity provides other benefits as well, such as attracting more pollinators and protecting the farmer from crop failure. If a pest goes unchecked, for example, and destroys the strawberry crop, the farmer still has all the other crops to sell. The same proliferation for a monoculture strawberry farmer, however, would destroy the entire season.
By simply choosing to buy organic you are also helping to protect all of the living creatures that call our bay home. The best way to support organic agriculture is to buy organic foods. Vote with your dollar! To find a farmer’s market near you check out the following website. If you want to know more, talk to the farmers. Learn about what their farming practices involve!
Hidden Villa also has a community sponsored agriculture program, in which participants pay at the beginning of the season for weekly baskets filled with seasonal produce. Here is a link to the CSA sign up. Support local agriculture that promotes bay health!
Stewardship challenge: For a whole day, pay extra close attention to where you food comes from. Make a map! Put a push pin in the map where you live or where your grocery store is, and a pin for where your food originates. Connect the pins with string—if your frozen veggies were grown in one place and packaged in another add another pin on the way to your grocery store! In order to do this you may need to ask someone at the butcher counter where your meat comes from (if unlabeled), and read packaging and labels closely.