1. Organic
Grain
Cropping
Systems
Vijay Bhosekar
February 13, 2015

2. Introduction
 Agriculture- age of declining fossil fuels.
 Every calorie food produced – requires- average 10
calories fossil fuel inputs (Richard Heinberg
(American journalist and educator)
 Biodynamic farming challenges- scientists and
farmers.
 Merit- soil quality, ecological impact, economics vs
conventional systems – needs more research
studies- long term efficacy.

3. Organic Cropping System
Developing a cropping system in organic production includes:
 Crop rotations and cover crops- pest management and
nutrient cycling
 Improving crop quality and yield by selecting plant varieties:
(a) adapted to diversified landscapes and growing regions,
(b) disease and / or pest resistant/ tolerant
(c) competitive with weeds

4.  Soils: INM system: holistic management, crops, feeds,
livestock, manures and composts enhancing
sustainability- organic production system.
 Pest management- broad spectrum of practices
(a) Cultural(crop rotation, planting date, row/ plant
spacing)
(b) Biological (genetic resistance, biodiversity, beneficial
organisms)
(c) Mechanical (tillage, row covers, traps, mulches)
(d) Greater understanding of pest biology
(e) Weed management strategies

5.  Organic production systems impact greater weed
pressure to conventional systems- potentially
causing yield losses and increased weed seed
build up(initial years).
 Use of competitive crop cultivars- cultural
practice of increasing seeding rates- moderating
weed management constraints.
 Organic grain cropping systems - enhance
number of ecosystem services Vs conventional
tilled (CT) systems.

6. 3 year studies 2011-14 Guelph suggest:
(a)organic grain cropping systems- could increase
several ecosystem services Vs conventional no-till (NT)
cropping systems
(b) Soil C sequestration, soil N fertility (N mineralization
potential) >, while global warming potential (GWP)
lower in organic systems using animal manures, cover
crops Vs conventional NT systems.
(Trial in progress)

7. Intercropping
 Increased choices,more interest generated -
organic producers.
 Diversification: plowed down in soil- different
crops feeding soil layers/zones; legumes-
nitrogen; cereals- organic matter.
 Last 50 or more years – breeding crops for high
input systems- SHOULD TARGET Organic
production.

8. Mean Yield OC - Farm Survey
1991- 96 (Canada)
Crop type Av. yield ( Kg/Ha) Yield range (Kg/Ha) Farm Sites
Hard Spring Wheat 1701 672-2690 119
Spring Wheat 1641 1008-2017 11
Soft White Spring Wheat 2542 1345-4371 13
Durum Wheat 2084 739-4035 6
Oat 1844 776-3429 77
Alfalfa 1627 457-2667 13
Fall Rye 2014 1255-3766 49
Barley 2205 0-4842 27
Buckwheat 753 269-1479 32
(Entz et al; Can. J. Plant Sci. 81(2): 351-4)

9. Crop Rotation
 Essential to any sustainable cropping system – more
imp in Organic systems- where producers can’t hide
problems of monoculture with quick fixes.
 Increasing nutrient content in grain crops.
 Maintain soil fertility, manage weeds, diseases and
insects.
 Long term organic rotation studies – future of Organic
systems- spring wheat, barley.

10.  Crop rotations: include greater crop phenological diversity -
improving nutrient management- reducing tillage intensity,
frequency.
 More diverse crop rotations- perennial grasses- reduce
weed pressure, economic risk, soil erosion, N2O emissions,
animal manure inputs.
 Increasing grain yield - soil fertility.
 Side-dressing animal manures in organic systems may
increase grain NUE - minimize animal manure inputs.
 Management practices: reduce tillage intensity, frequency-
reduce soil erosion, labor, energy needs.
(Cavigelli et al (2013) Renewable Agriculture and Food Systems
(2013) 28: 145-159)

11. Green Manures
 Energy efficient N: simple and inexpensive fashion-
GM cover crops (hairy vetch) in spring residue
production or N contribution.
 Cornerstone of sustainable agriculture - should
always be included in sound organic crop rotation.
 In Crop Rotation: winter annual species – fall rye,
winter wheat, oat, barley, forage grasses build OM;
tillage: key tool – terminating and incorporating
green manure as well weed control.
 Organic producers – provide N, build soil organic
matter reduce weed pressure.

12.  Hairy Vetch and Cereal Rye: R- germinate, establish
effective root systems- lower soil N conc.
 HV- more nodulation, fix more N- when soil N low.
 Rye fibrous root web prevents frost- heaving damage to
over wintering HV; tall strong R stems- support V during
rapid spring growth.
 Biomass production, weed suppression best under
combination.
(Treadwell et al; 2010 Weed Res 50: 597- 605)

13. Cover crop diversity – Organic CS
 Organic grain CS - intensive mechanical cultivation-
weed control, manure, compost applications - meet
plant nutrient demands.
 Cover crops:weed suppression, improve soil fertility-
potentially increasing crop yield hence sustainability of
the system.
 Utility of individual cover crop species: well
documented agronomic benefits;diverse cover crop
mixtures- less attention bestowed.

14. Cover crop mixtures- diversity
 Sorghum – Cowpea: utilize more below- ground, above-
ground niches- nutrients like water and light.
 S: heavy N feeder tall upright growth habit.
 C: fixes N – dense canopy between S stalks.
 Allelopathic S: densely shading C, delivers one – two
punch on weeds.

15.  Cover crop mixtures: appealing option- farmers-
increasing species diversity, increase resource-use
efficiency,stability,resiliency, productivity- plant
communities.
 Growing interest in cover crop mixtures- little is
known - effect of increasing cover crop diversity on
cropping system performance.
 Moreover, organic farmers: questions - most
effective method for cover crop mixture
termination.
(Lindquist et al; 2013 Weed Science 61: 353-4)

16. Tillage
 Key tool: OMAFRA disc roller: turn down GM crops
leaving residues on surface- suppress weeds for
seeding next crop.
 Beneficial goals: weed control, seed bed
preparation. Spring tillage not desired- uses time,
energy and water, potential to reduce soil quality.

17. Sustainability of Organic Grain Cropping
System Review
 Cropping system comparisons: inherently challenging - since both
organic- conventional systems; characterized-range of management
practices which vary according to site-specific requirements: farmer
choice.
 Agronomic challenges: addressed; organic systems- effective weed
control, improved fertility management.
 More research is needed to ensure production sustainable for long-
term.
 Further research needed fully understand - impacts of long-term
organic management – available soil phosphorous to optimize
cropping systems and management standards accordingly.

18.  Importance of price premiums: ensure economic
viability of organic producers; preservation high-value
niche market-important; ongoing sustainable organic
production.
 Higher prices: organic crops - lower production costs;
organic system - higher per-acre net returns Vs
conventional operations.

19.  Organic systems:complex; great deal of
experience, expertise - managing organic
rotations, by research scientists and farm
managers.
 Where crop land is limited- organic crop
management is more attractive.
(Snyder and Spaner; Sustainability (2010) 2: 1016-34)

20. Organic in Canada
 2011: 3713 certified organic operations.
 accounting for 1.8% of total operations.
 Saskatchewan: largest number of organic operations followed by
Quebec.
 2001- 2011: total farms less by 17%, organic farms increase 66%.
 2012: organic market worth $ 3.7 billion- $ 3 billion spent on certified
organic foods.
 Organic foods: 1.7% of total food sales, 58% Canadians buy organic
products/ week.
(COTA, 2013)

21. Summary
 Non legume cover crops: grasses, small grains do not fix N-
but could be effective, recovering mineralized N from soil-
after crop harvest.
 Cereal Rye, Wheat- residues C: N ratio > 25:1- slow
decomposition rate- N more slowly released.
 Beneficial- planting mixtures: cover crops allelopathic
potential- supress weeds manage broader spectrum weed
control.
 Important grass cover crops: fit in Organic grain CS- Cereal
Rye, Annual Rye Grass, Japanese Millet, Wheat, Barley,
Oats.

22. Thanks very much for
Your
Time, Patience and Energy