3/5/2013. Performance of Organic Farming Systems and Implications on Climate Change

Transcription

1 3/5/213 Performance of Organic Farming Systems and Implications on Climate Change Erin Silva, University of Wisconsin March 5, Presenter: Erin Silva, University of Wisconsin Performance of Organic Farming Systems and Implications on Climate Change Erin Silva and Janet Hedtcke UW-Madison, CIAS and Agronomy Dept. 3 1

2 3/5/213 The Wisconsin Integrated Cropping Systems Trial Arlington site Fe 22, 213 Organic Farming Conference, La Crosse, WI 4 Wisconsin s organics tops the national ranks #1 for total organic livestock # 1 for field crop acreage #1 for total organic milk cows (22% of USA total) #2 in organic milk sales (64% of organic sales) #2 in organic farms (n=1159 farms) # 1 in vegetales Organic dairy and livestock farms drive market for organic feed Source: UW-Madison CIAS/DATCP 212 status report 5 WICST was orn in 1989 Two locations: Arlington (well drained silt loam soils) Lakeland (more-poorly drained silt loam soils) Over 2 years of data summarized: from 1992 to 212 Trends emerging Economics Soil caron Yield trends Weed seed WICST: Lakeland site 6 2

3 3/5/213 Cash-grain systems Continuous corn Strip-till corn-soyean Organic grain 7 Dairy (forage-ased) systems Conventional Alfalfa Organic forage Managed grazing 8 Effect of weed pressure on corn yield Conventional (min-till corn-soyean) Wet Springs (May + June >1 rain) Normal Springs ARS LAC ARS LAC u/a Organic (3-yr grain) Org:conv 72% 76% 96% 94% 9 3

4 Bu/acre 3/5/213 Effect of weed pressure on soyean yields Conventional (min-till corn-soyean) Wet Springs (May + June > 1 rain) Normal Springs ARS LAC ARS LAC u/a Organic (3-yr grain) Org:conv 79% 76% 95% 92% 1 3 rotary hoe or tine weeder can do ~ 3 acres/hr 11 Corn yields in extreme weather yrs 25 2 a a xy x y c z z cont. corn strip-till corn-s conv. dairy organic grain organic dairy 28 (flood) 212 (drought) 12 4

5 Yield, u/a 3/5/213 Rodale Corn in the legumeased (left) and conventional (right) plots six weeks after planting during the 1995 drought. The conventional corn is showing signs of water stress. 13 Rodale -Organic corn yields were 31% higher than conventional in years of drought Or Organic 14 Conventional vs. Organic Corn Yield Trends 25 2 Conventional Corn 15 1 Organic Corn-in 3-yr grain system Cycle 5

6 Yield, u/a Yield, u/a Yield, t dm/a 3/5/213 Conventional vs. Organic Corn Yield Trends 25 2 Conventional Corn 15 1 Organic Corn- in 3-yr forage system Cycle Conventional vs. Organic Soyeans Organic Conventional Cycle Conventional vs. Organic Alfalfa Organic 4. Conventional Cycle 6

7 $/acre $/acre 3/5/213 Base Gross Margins (GM) GM = Crop revenue variale costs Grain priced at harvest; hay priced in winter Gov t payments included Feed-grade organic premiums included Systems scaled up to farm size 12 acres for conventional grain farms 6 acres for organic grain farm 15 acres of conventional and organic forage farms 19 Historic GM of grain systems Conv. min-till corn-s a Organic grain (c-s-w) Conv. min-till Organic grain corn-s (c-s-w) ARL ( ) LAC ( ) x y Org premium Gov't payment Base GM 2 Historic GM of forage systems Convent. Forage a Organic forage x Convent. Forage y Organic forage Org premium Gov't payment Base GM ARL ( ) LAC (1992-2) 21 7

8 $/u $/acre $/u /5/213 Corn and soyean feed-price trends (at harvest) organic corn conv. corn 3 2 organic soy conv. soy $3 $25 $2 Fertilizer cost in corn phase at ARL ($/acre) $15 $1 $5 conventional (c-s) organic (c-s-w) PEPs corn grain $- 23 Corn seeding cost at ARL ($/acre) reseeded 6 4 conv organic PEPs, grain

9 $/acre $/acre $/acre 3/5/213 Soyean seeding cost at ARL ($/acre) conv organic 25 Total expense in grain systems (ARL) conv. grain organic grain Total expense in forage systems (ARL) conv. forage organic dairy

10 $/acre Tons C/a in 3 ft profile 3/5/213 Gross margins in 2 decade-arl f f f de ef c cd de a Era (E): p<.78 System (S): p<.1 E*S: p<.1 cont corn strip-till corn conv. dairy organic grain organic dairy Era 28 Soil Organic C changes over 2 yrs-arl cont corn no-till c-s org c-s-w conv alfalfa org alfalfa pasture c a Soil C inputs on WICST ARL ( 92-9) LAC ( 92-2) System ls C/acre -1 Cont. corn Min-till corn-s Org grain (c-s-w) Conv. Forage Organic Forage Pasture with managed grazing

11 Tons/acre 3/5/213 RUSLE2 Soil loss estimates (18-yr avg, ARL) assuming 4% slope, 15 ft run, contours cont corn no-till c-s org c-s-w conv alfalfa org alfalfa pasture N 2 O emissions/unit of N harvested-arl C and N changes in other Long-Term Studies LTAR (Iowa) - Total nitrogen increased y 33 percent in the organic plots higher concentrations of caron, potassium, phosphorous, magnesium and calcium results suggest that organic farming can foster greater efficiency in nutrient use and higher potential for sequestrating caron 33 11

12 3/5/213 Rodale FST - in oth organic and conventional systems, the highest overall GHG emissions were caused y soil processes fueled y nitrogen fertilizer, compost, and crop residues 34 Rodale FST Organic system uses 45% less energy mainly from not allowing conventional fertilizers 35 Demand for non-renewale energy resources of the farming systems in the DOC experiment ( ) per hectare and year (columns) and per kg dry matter (DM, line)(nemecek et al., 211) 36 12

13 3/5/213 LTRAS (California) 37 Conclusions Yields: Org:Conv >9% when weeds controlled Organic yields etter than continuous GM corn in extreme weather years Organic yields similar to rotated GM corn in extreme weather years Yield trends Corn increased at 2.5 u/a/yr (same for organic and conventional) Soyeans had slight gain at.2 u/a/yr (same for organic and conventional) Alfalfa no real trend yet 38 Conclusion (cont d) Profitaility: organic >conventional Gross margin higher in last 5 yrs. vs. previous 5 yr Large part of the profitaility is coming from strong and steady premiums (in this study feed premiums) Inputs (seed, fuel, and nutrients) are driving up expenses, often near to the cost of conventional inputs Ecosystem Services All systems losing caron other than pasture Expand rotation with alfalfa can reduce soil loss GHG lower under rotations ut not necessary due to organic management 39 13

14 3/5/213 Find the slides and recording of this presentation at Register for upcoming weinars and view recorded eorganic weinars at p:// Additional organic farming questions? Ask them at We need your feedack! Please fill out our follow-up survey! 14