Sustainability is difficult to define, but essential to understand and try to implement. My first memory of the concept (but not the term) was the photo of Earth taken from the Apollo spacecraft. That image etched the idea of "limits" into my consciousness, and limits or system boundaries are key aspects of sustainability.
One of the best-known definitions is from the United Nation’s Brundtland Commission: Sustainability is meeting the needs of today without compromising the ability of future generations to meet their needs. This has to do with balancing economics, environment, and people. It is not a new concept. Romans recognized it in their recommendations to use legumes to restore worn-out soils. Unsustainable grazing in Mesopotamia led to soil erosion that clogged the lowland irrigation systems, and our Dust Bowl was a homegrown demonstration of lack of sustainability. Sustainability in agriculture involves more than the farm—it touches the larger ecosystem, the communities in which farm families and workers reside, and the need for access to health-promoting foods for the larger population.
Since sustainability includes a time dimension, it is generally easier to understand what is not sustainable than what is. With hindsight being 20/20, the sustainability of actions taken decades ago (e.g., lead arsenate pesticides) is easy to evaluate. It is harder to say whether new pesticides used today will ultimately be sustainable. Already, scab-resistant apple varieties are succumbing to apple scab in some European countries, and pest resistance to codling moth granulosis virus is also appearing.
I think a big challenge is trying to anticipate the system effects of the actions we take. Labor is clearly a sustainability issue for the tree fruit industry. Moving to more mechanization can help reduce labor needs and hopefully production costs. It will require changing the orchard design, which may alter light, temperature, wind speed, and other factors. Do we understand the biological implications of this? How will it change pest dynamics? Already we have experienced increased fruit sunburn in moving to high-density dwarfing orchards, and we use evaporative cooling to control it. With summer water supplies likely more constrained by expected climate change, this practice may no longer be an option.
Our tree fruit industry is making many changes that enhance sustainability. Pest management is a good example—areawide management, "soft" pesticides, new monitoring tools, decision support systems, "rose gardens" to support beneficial insects—the list goes on. With new fruit varieties and products, increased emphasis on fresh fruits and vegetables, a growing population, increasing incomes in other countries, and a positive impression of products from Washington (say compared to China), our tree fruit products should enjoy strong demand that is a prerequisite for economic sustainability.
Since energy drives everything we do, the industry needs to start looking at alternatives to fossil fuels, which will become increasingly expensive and hard to get. How can we conserve energy in the orchard and possibly produce energy there? Fewer tractor trips, use of biodiesel, legumes for nitrogen, and better transport logistics are steps that can be taken right now. Future ideas include electric tractors (a gas tractor was recently converted to electric in Chelan); using orchard biomass like cull apples to produce fuel; combining new printable solar collectors with undertree reflective fabrics, helping with tree performance while also generating electricity; and dedicating parts of the farm to energy production. Transport energy to take fruit to market is another looming problem. The recent expansion of RailEx service from Wallula to New York is probably a sign of things to come, as rail uses about one-fifth the energy of highway trucks.
One last area to consider is climate change. Fruit breeding will need to enhance the adaptability of trees to more extreme temperatures and possible late-season water shortages in some areas. Dr. Greg Jones of Southern Oregon University and others predict a steady shift of wine grape varieties to the north (and in Washington perhaps from east to west) as the climate warms. The environment might become suitable for crops not currently grown; fruit crops grown elsewhere, like plums and prunes in California, might migrate to Washington if their former home no longer has an amenable climate.
We can expect the world to be quite different in 20 years than it is today, but are we adequately planning for it? Growers, companies, and the industry can start now by developing a range of possible scenarios, considering major drivers like energy, climate, labor, demographics, and global economics. Look for actions that, regardless of the scenario, would have a positive sustainability outcome. This is the "no regrets" idea. Energy conservation is a good example that, regardless of the future, is a "sustainable" step. Some actions will be new technologies, others changed behavior.
While sustainability is hard to pronounce and difficult to define, I believe that it is a valuable organizing concept for the problems we face in the twenty-first century. It requires more peripheral vision and more humility. Author Wendell Berry alluded to this by saying, "We don’t know what we are doing [in agriculture] because we don’t know what we are undoing." We need to acknowledge the limits of our understanding as well as the limits of the planet to support us and other species.