Organic Agriculture. Organic Agriculture. Michael Bomford, PhD Kentucky State University

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1 Organic Agriculture Organic Agriculture Michael Bomford, PhD Kentucky State University

2 Past 40 years: Doubling of grain yield 700% increase in fertilizer use 70% increase in irrigated cropland Now ~40% of land surface Food production Mean yield of 23 main food crops (million kcal/ha) Developed world Developing world Adapted from Green et al Farming and the fate of wild nature. Science 307:

3 Agricultural land use 25 Cropland Developed world Developing world 45 Pasture % of usable land % of usable land Adapted from Green et al Farming and the fate of wild nature. Science 307:

4 WorldWatch, 2000

5 Agriculture threatens bird species Developed world Developing world Percentage of threats attributable to agriculture Threatened Near Threatened Adapted from Green et al Science 307: Data from World Bird Database, BirdLife International.

6 N and P fertilizer use Developed world Developing world Developed world Developing world 50 N fertilizer 40 use (Million metric tonnes) P 2 O 5 fertilizer use (Million metric tonnes) International Fertilizer Industry Association

7 Nitrogen groundwater contamination High vulnerability: Shallow groundwater Well-drained soils Little forest USGS

8 Water pollution

9 Changing Face of US Agriculture Farmers (millions) Farm fuel use (petajoules)

10 Agricultural Energy use Animal Production 8% Irrigation 13% Crop Drying 5% Pesticide Production 5% Misc. 3% Transportation 16% Machinery Operation 19% Fertilizer Manufacturing 31%

11 Energy inputs per food calorie Farming, 1.6 calories Household storage and preparation, 2.3 calories Transport, 1.0 calorie Food retail, 0.3 calories Processing, 1.2 calories Packaging, 0.5 calories Commercial food service, 0.5 calories M.C Heller and G.A. Keoleian (2000). Life Cycle-Based Sustainability Indicators for Assessment of the U.S. Food System. University of Michigan

12 Albert Howard ( ) British agricultural scientist. 25 years in India. Critical of reductionist agricultural science and specialization Blamed fall of past civilizations on unsustainable agriculture Wrote An Agricultural Testament (1940)

13 Howard on Chinese agriculture The small-holdings of China, for example, are still maintaining a steady output and there is no loss of fertility after forty centuries of management.

14 Howard on Eastern agriculture Small farms Mix of people, plants and animals; wastes recycled as nutrients Human and animal labor, not machines Food crops, not cash crops (subsistence) Nitrogen fixed by legumes Reduced cultivation Composting Mimic natural ecosystems

15 - Large, growing farms - Monocultures - Mechanization - Synthetic fertilizer dominates - Increasing crop disease - More processed and preserved foods - Success judged by profit - Too much food (low prices force farmers off land and into cities) Howard on Western agriculture

16 Lady Eve Balfour ( ) Among first women to graduate from University of Reading (agriculture) 1939 began long term experiment comparing conventional and organic production 1943 wrote The Living Soil 1946 founded the Soil Association Healthy soil, healthy plants, healthy people. Soil Association (2003) / Mary Erstman

17 J.I. Rodale Bought farm in PA to test Howard s ideas Popularized term organic, through his Organic Gardening and Farming magazine Relationship with science Presented reader testimonials as research ( science for the people by the people ) Solid long-term research trials continue

18 Lady Eve Balfour ( ) Jerome Irving Rodale ( )

19 Organic Production Standards Organic agriculture is a production system that is managed in accordance with the Act and regulations in this part to respond to site-specific conditions by integrating cultural, biological, and mechanical practices that foster cycling of resources, promote ecological balance, and conserve biodiversity. USDA ORGANIC

20 Organic Production Standards Land is certified by gov t-approved agencies Farmer develops and follows organic farm plan Synthetic substances prohibited Includes synthetic organics Natural substance allowed Includes natural inorganics Maintain or increase soil organic matter content Separation from conventional products In time 3 year transition period In space buffer zones, barriers, separate containers, equipment cleaning etc. $10,000 fine for misuse of word USDA ORGANIC

21 U.S. organic food sales have grown between 17 and 21% each year since 1997 (total U.S. food sales over this time have grown in the range of 2-4% a year) Organic food sales represent approximately 2% of U.S. food sales. Billions of dollars (Organic Trade Association s 2004 Manufacturer Survey)

22 US Organic Farms, 2006

23 Clear Boundaries & Buffers Conventional Organic Buffer Conventional

24 Soil Fertility: Cover Cropping Soil organic matter (%) WVU organic research project Winter rye & vetch cover crop Cover crop + Rye/vetch mix adds ~135 lb N/ac Slow release Organic matter Erosion control

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28 Soil Fertility: Animal Waste

29 Soil Fertility: Animal Waste Raw manure pre-harvest interval: > 90 days if edible portion does not contact soil > 120 days if edible portion contacts soil

30 Soil Fertility: Compost No pre-harvest interval Strict requirements for manure-based compost F for 15 days in windrows C/N = 25-40

31 Pest Management: Solarization and Biofumigation

32 Pest management: Resistant varieties

33 Pest Management: Natural Enemies

34 Pest Management: Farmscaping

35 Pest Management: Botanicals Chemicals derived from plants Rotenone rat poison, very toxic to fish, linked to Parkinson s allowed under NOP; temporary ban in Europe Pyrethrum neurotoxin, quick knock-down chemistry inspired synthetic pyrethroids Neem inhibits moulting

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37 Pest Management: Microbials Bacteria e.g. Bacillus thuringiensis Fungi e.g. Coniothyrium minitans Nematodes e.g. Steinernema

38 Pest Management: Oils & Soaps Oils Petroleum / vegetable based kill through suffocation most widely used insecticide, by weight Soaps kill through desiccation (penetrate protective waxy covering) mainly kill soft-bodied insect No resistance observed to these modes of action