In last month’s column, I shared the first half of my interview with farmer and University of California (Los Angeles) Professor Stephanie Pincetl, Ph.D. Pincetl’s lab at the Institute of the Environment and Sustainability collects and assesses data about urban ecology, as well as urban resource use, and explores the possibilities for green infrastructure. As a farmer with an orange grove in Ojai, California, Pincetl is always thinking about the relationship between the city and the natural world, especially the agricultural landscape. She says the postcarbon farm looks like “a much greater integration of the farm with the city.”

In Pincetl’s vision of the post-carbon agricultural system, organic waste from the city can be recycled through compost and manuring for the farm. Solar energy is used more in food processing. To shorten the supply chain, the land around cities is preserved for agriculture as much as possible. However, this doesn’t mean you have to move your operation.

GROWING: DOES THE POST-CARBON AGRICULTURAL SYSTEM CHANGE THE LOCATION OF FARMS?

PINCETL: The distinction now between urban and rural is a little fuzzy. You have to consider what your food miles look like. If you’re talking about the amber waves of grain, maybe you’re talking about long-distance transport by rail that is electrified. If you’re talking about produce, you can talk more about an urban food supply — greenhouses that are heated with geothermal, or kept warm with manuring and peri-urban intensive agriculture.

If you’re talking about fruit crops — like stone fruit — some fruit grows in certain places, not everywhere. It’s also about rediscovering crops that can grow in climates where they are more specialized. We have moved toward monoculture crops that are easier to grow anywhere, like certain species of apples. But there are other species of apples that may tolerate the cold better or heat better.

It’s about returning to the question of soil and climate and diversifying the species of plants that we use for food and expecting less high yields in some cases. Intensive biodynamic farming has very, very high yields, and it’s also very labor intensive. The response is regional. How post-carbon looks will vary in different places. Because climate and soils are different, growing conditions are different. We will get more appreciation for what that means when we eliminate or reduce the use of fossil energy, whether for fertilizer, fuel, pesticides, herbicides, etc.

GROWING: IS THERE ROOM FOR HYDROPONIC AND SOILLESS GROWING SYSTEMS?

PINCETL: If the whole lifecycle accounting takes place, the room for hydroponic growing will be very small. Where’s your water going to come from? How is it going to get there? How are you going to filter stuff? All of that requires energy. If you can do it without fossil fuels, sure; but I don’t think it’s an answer. I think it’s a technical innovation seeking a home.

GROWING: WHAT ABOUT FOSSIL ENERGY IN THE POST-CARBON FARM?

PINCETL: The time frame is very important to think about. The transition is very important to think about. I think that there’s a role for fossil energy in the world going forward. What it is, I’m not quite sure yet. For example, plastics in medicine are pretty valuable — prosthetics, IV drips and things like that. I think that going forward what we have to do is consider the highest and best use of fossil energy.

If there are farm applications in which fossil fuel can be used in an extremely effective manner, I’m not going to say “No way.” But I do think that we have become enormously sloppy with this very, very valuable resource. My feeling is that we should treat it like gold. We don’t waste gold. Gold is used for the right applications. Most of the gold that’s been mined in the world is still in circulation. So if we think about fossil resource, of which there’s a lot but [it’s] becoming harder and harder to extract and more and more expensive and having all these very serious impacts. If we think of it as a valuable resource that has serious impacts, but that we can use parsimoniously well, I think that’s a good thing to do.

GROWING: IF THERE’S BEEN ONE THEME TO THIS CONVERSATION, IT’S THAT WAITING FOR THE ONE GROUP OR THE ONE PERSON TO TELL US THE ONE ANSWER IS NOT GOING TO WORK.

PINCETL: There’s not one solution. There’s this drive in society to find a magic bullet to solve all the problems, but we live in places. The magic bullet is to reconnect with those places and act in partnership with those places.

People complain [that] there are no seasons in Southern California. Excuse me — we have no seasons because we have occluded the changes that happen through over-irrigation. If we moved to a more native plant palette and got rid of the lawns, we would know the seasons. We would know it’s summer [because] it’s really dry. The leaves are crinkled. It’s deciduous in the summer. And they will know that it’s spring because it’s so lush and it’s unbelievably green. We do have actual real seasons here, but we have distanced ourselves from our place.