Introduction to Agricultural and Food Systems
Introduction to Agricultural and Food Systems AFS 101
Popular in Course
Popular in Agricultural And Food Systems
This 56 page Class Notes was uploaded by Nat Goldner on Thursday September 17, 2015. The Class Notes belongs to AFS 101 at Washington State University taught by Staff in Fall. Since its upload, it has received 62 views. For similar materials see /class/205990/afs-101-washington-state-university in Agricultural And Food Systems at Washington State University.
Reviews for Introduction to Agricultural and Food Systems
Report this Material
What is Karma?
Karma is the currency of StudySoup.
You can buy or earn more Karma at anytime and redeem it for class notes, study guides, flashcards, and more!
Date Created: 09/17/15
Chemical Weed Control Ian Burke WSU Weed Science Methods of Weed Management Preventative Cultural Mechanical Biological Chemical Topics What s a herbicide How are herbicides registered How are herbicides classi ed How are herbicides used Where do they go Topics What s a herbicide How are herbicides registered How are herbicides classi ed How are herbicides used Where do they go Herbicide use patterns are directly related to the discovery and registration process What s a herbicide Herbicide has been de ned as any chemical substance or cultured biological organism used to control or suppress plant growth What s a herbicide Herbicide has been de ned as any chemical substance or cultured biological organism used to control or suppress plant growt If there is any claim of activity then it is classi ed as a herbicide and must be registered for use Herbicides as Tools Selective chemical weed control Mechanically powered implements introduced Row crop cultivation with animal power I POGFIIB 1 Brian 2 my Eg IP l l United States Only 33 people 16 mph B FIme 75 people mom ac loot B I n aim Crop output per farmer SQUAD Team 193nm 1590 AD E Less than 930 Herbicide Use in Soybean and the Impact of GM Soybean on Herbicide Use Numm o of soybean area 30 Number of herbicide treatments 80 Pounds per acre 01 active ingredient 70 60 50 Glyphosate 4O 30 HT seed 1996 97 98 99 2000 1991 93 95 97 99 2001 Herbicide Use in Soybeans 2008 Soybeans Percent of Acres Treated and Total App lied Percent 000 lbs El Percent Treated 0 Total Applied 90000 80000 70000 5 O 60 000 50 000 40000 30000 55 50 45 40 35 30 25 0 20000 10000 0 Glyphosate isoe salt 24D 2EHE Lambda Chlomyn39fos Glyphosate cyh alolhrin Active Ingredienl mew of mm mm BY EPh I39HIEETO MM mmu 0N HMLTH AND mmu BilIE Why Do Companies Develop Herbicides Give Shareholders a Good Return on Their Investment What is a Good Investment I A product that Will fit any one of the big five markets Cereals Corn Cotton Rice Soybeans and can competitively fulfill a need in the market place equal to or better than the best registered CPC in that market I Investment return must exceed the cost of development amp marketing amp yield a good profit I A product that is environmentally friendly Investment amp Return 300 200 100 100 200 Year Year Year Year Year Year Year Year Year Year Year YearYear YearYear Yea rYear 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 Discovery Scientists looking for new chemistry with crop protection activity by 1 Searching literature for new ideas 2 Modeling promising structures 3 Purchasing new chemistry from commercial producers Often new herbicides are structurally similar to previously discovered herbicides Discovery Should a product be developed Ef cacy Crop tolerance Toxicology Effect on nontarget species Ease of synthesis amp cost to produce Availability of intermediaries Resistance 999 WNH Screening One in 20000 may be registered Screening Organisms are placed in cells and treated with the new product New technology makes evaluation more efficient Primary screening for fungicidal herbicidal insecticidal and nematicidal activity Secondary screens expand the number of crops and pests checked for tolerance Early toxicology mutaginicity and reproductive studies are conducted HOW Are Herbicides Registered I Residue I Development I Registration I Labeling I Stewardship Some toxicological data required for herbicide registration Mammals Fish and Wildlife Acute Fish and Aquatic Organisms gral ED301350 Acute 90 hr LCSO errn Primary dermal irritation trom Primary eye irritation Inhalation LCSO 39 mm Shrirnp oysters crabs Subacute Chronic LCSO on fathead minnow Dermal Reproduction in Daphnia Dermal sensitization Oral feeding 90 days Birds Teratology Acute LDSO Neurotoxrcrty Subacute dietary LCSO Imam Mallard duck Chronic Feeding and Oncogenicity BOWInt qua 24 month feeding on two or more species 39 RePTOdHCUOH 1 mallard duCkS Reproduction three generations in rats Mutagenicity Bacteria Somatic cells Living organisms Dia ostic rst grid palliative and antidotal information mus be provrde Mutagenic capable of causing genetic changes Oncogenic capable of producing or inducing tumors in animals either benign non cancerous or malignant cancerous Field testing amp environmental studies I Studies to identify markets develop marketing amp development plans are initiated by steering committee I Field testing begins in the US amp various locations throughout the world utilizing company Dev Reps University Researchers amp Private Contractors I Prior to registration experimental use permits are obtained for large scale testing Residue Development I Residue studies are conducted on all crops being considered for registration to establish tolerances amp set preharvest intervals I May take 2 3 years with completion scheduled for 2 years prior to labeling I Trials are established with GLP cooperators or conducted internally I Cost per trial ranges from 5000 to 25000 Need a minimum of 5 per crop or crop grouping Registration I Field testing determines crops pests use rates amp application timings I Residue data determines preharvest intervals I Toxicology data determines precautions for application reentry amp worker safety I Submit package to EPA at a cost of 250000 and wait 2 years Registration EPA will issue questions amp may request more studies eventually tolerances are set and labels granted Each product is assessed and tolerances determined by residues detected and relationship to dietary risk cup EPA allows each company a limited number of slots each year for submission of registration packages for both new amp established products Companies select slots on the basis of market potential Labeling The Ticket to Market I Section 5 EUP I Section 3 EPA label I Section 18 I Special Local Needs or 24C I Supplemental label Section 5 Label A FIFRA Section 5 registration is generally called an Experimental Use Permit EUP A herbicide manufacturer may apply to the EPA for an EUP for a herbicide before it is granted full registration The purpose of the EUP is to provide a mechanism by which the applicant can accumulate herbicide performance information under fielduser conditions and provide supplemental data required for registration The EUP is typically requested near the end of the registration process usually 1 to 2 years before full registration is anticipated Section 3 Label I Package label contains Safety precautions Directions for use Crops registered on Pests controlled and suggested use rates Signal words Caution Warning Danger Section 3 Label Once registration is granted the label becomes a legal document that gives the manufacturer the right to sell the product Under the law any person misusing or recommending use of a pesticide contrary to label instructions is liable to prosecution and possible nes a jail sentence or both Some exibility is allowed 5300335410 Canlams sen gums per mg m 55 pnunds per us gallon 0H IB acme ingredient glyphosale in LIISIOIIII oI its pmssiimi saIt Equivalent In 541 gums pei Iner oi M pounds FBI 8 gaIlon Uitie acid gig39le Sil is product IS maimed IJj US Patent Nu s 5558015 RE 37356 JIIII 6365551 en imam pending Nu Iioensa granted undei any nunU 5 pounds Tli ox 0 IMPORTANT PHONE NUMBERS 1 FOR PRODUCT INFORMATION OR ASSISTANCE IN USING THIS PRODUCT CALL TO LF EE 18003323111 1 IN CASE OF AN EMERGENCY INVOLVING THIS HEPBICIDE PI39IODIJCK OI FOP MEDICALASSISTANCE CALL COLLECT DAV 0R NIGHE 314 44000 t8 10 PRECAUTIDNARY STATEMENTS 1 Hazards to Humans and Domestic Animals 55755ch Keep out of reach of children CAUTION CAUSES MODERATE EYE IRRITATION H RNFUL IF INHALED m 39Specially formulated for Roundup Ready39crops Complete Directions for Use EPA in No 5247537 AWILI UDIITACI DP NERBICIDE VIITN FLILIIBE GREEN STENS BIFEISED NONWOOIIN ROUTS DR FRUIT OF DROPS iEXEEPT A3 SPEEIFIED FUR INDIVIDUAL RGIINDUP READY39 CROPS DESIIMELE PLANTS AND TREESI BECAUSE SEVERE INJUW 0R DESTRUCTION MAT RESULT Hsrnicide for Roundup Ready Emps Selective broadspectuim weed EMIth m Roundup Ready crap I39Iuniseleci i3939e hmadAspechum weed normal for manyagricuhural systems and mum cnIIecl day a night IN EUUFL NotaII muducts iecomniended on this Iqbal ave registered I0 use III CaIiIumia Check XI regiuimtian mm acli pin m in alifoinia heme using Read the mile IaheI hafnre using Ihis pmduct Us only amending m Iahd Instimions Read the quotLIMITOE MRMNI V MID LIABILITYquot smlavlem at the end if Ihe Iobd befnie a pmbie val 1 Wm u v L if mm nrhnnquot cattgm seIealon chart MIXGIS Luaders ULher Handlers and upplivaloni when IIaIIdIITIg this cminenuala Tml39sr39 grm39ggtig03303mswgrgsignmq MENU MD W W piaduci OVIIS ainplicaiiun soluiinns at 30 paicsiii cancammlon or gream l llllSl 39 3 wear lungslanted shin and hug panlzi sine sacks 3le DIIEmImII shm gem REEISTEREEJI FIOR IREOIMUMWN SEE INDIVIDUAL CONTAINER UBEL FOR madeaianywatamoolmaieriaIswimsobetmieueumbnimidiluiida NE NCIWSI L LIIINTO S nnn mmr V I IS Fm NET DE 655 quotWEE WEHE 07143249 5 III J DlIg WINS S 86 an 0 INGREDIENTS II39 II I I d h dl h I FLIInw mamrIadurer s instrumons fm cleaningmaimlmng PFE Parsonal imam fem LNGREDIENF Equipmnu If nn siwll insinlc nns m woshables Ilse demeem and hat mm Heep GlitmvIsme NivleviwomalRWW 88 mm m wamel mm m n m 3 oassulmsa 5 mHEEMREmENTPX WW u n u I mum cabsoawaitinamannermimeis mm me requirements mm m Walker Prdmion mm m Io giicquIIaI pis cdes a PULL HERE TO OPEN FL RESTRICTED USE PESTICIDE DUE TO ACUTE TOXICITY FOR RETAIL SALE TO AND USE ONLY BY CERTIFIED APPLICATORS OR PERSONS UNDER THEIR DIRECT SUPERVISION AND ONLY FOR THOSE USES COVERED BY THE CERTIFIEDAPPLICA TOR S CERTIFICATION GPA MDXONIEW INTEDN A Weed Grass and Harvest Aid DesiccantDefoiiant Herbicide Active IngredI e T NEVER PUT INTO FOOD DRINK OR OTHER Paraquat dich ldE 1139Edimethr44 v CONTAINERS bipyridinium dichloride V V V V V V V V V o 3019 IFSWALLOWED TAKE IMMEDIATEACTIONAS other Ingredients 699 PRESCRIBED IN FIRSTAID STATEMENT SYMPTOMS Totaf 100W ARE PROLONGEDAND PAINFUL Contains 20 pounds paraquaz can39on per gaifon as 2762 39 DO NOTUSE OR STORE IN OR AROUND THE HOME pounds salt per gaIIon Contains alerting agent a dear 39 DO NOT REMO V5 CONTENTS EXCEPT FOR emetic dye and Inteon TechnoD IMMEDIATE USE DY KEEP our OF REA CH OF CHILDREN 39 E I g k g i swi i g a NOT FROM MMOUAT DA NG E R PE LI GRO Si usted no entiende Ia etiquefa basque a aIg39uI39en para que se Ia expIque a usted en detaIIe I l f you do not understand the IabeI find someane f0 epraI39n It to you in detaI39I EPA Reg No 1001217 EPA Est IOUTXOOI SCP 1217AL1A 0206 25 gallons Net Contents syng39enta Section 18 I Used in emergency situation new problem threatening agriculture amp no way to control it I A temporary tolerance granted amp a restricted use rate and time frame for use I Request must be made by the state Section 18 1 Speci c exemption this authorizes use of an unregistered pesticide in an emergency to prevent a signi cant economic loss or a signi cant risk to endangered or threatened species bene cial organisms or the environment 2 Quarantine exemption this may be authorized to control the introduction or spread of any pest not known to be widely prevalent or distributed in the United States 3 Public health exemption this authorizes use of the pesticide to control a pest that poses a signi cant risk to human health 4 Crisis exemption this may be utilized in an emergency condition when there is an urgent immediate need for the pesticide upon discovery of the emergency and time does not allow for the authorization of a speci c quarantine or public health exemption Section 24C Special Local Needs I Issued by state subject to EPA approval I Meets special local need I No current product will work amp it is a localized need I Must have an EPA tolerance for that use I Is reviewed by states every 3 years Supplemental Labels I Issued by EPA can be used to add a crop or weed species or new usage I Is faster way of labeling an established product without having to review the whole label I Some states require it in hand when product package label can t be rapidly changed Good Stewardship I Register products that can be used safely amp live up to the label I Write labels that will enable the customer to use the product successfully I Warn consumers of precautions that need to be followed I Help customer use product in a prudent manner Current status Toxicology and environmental testing requirements established by the EPA have become more extensive in recent years and many herbicides registered in the 1960s and 197 Os were granted registration before the more stringent requirements were established In addition to requiring that pesticides be classi ed as either general or restricteduse pesticides the 1972 F EPCA amendment to F IFRA requires that older products be reregistered Current status The 1988 version of FIFRA requires pesticide manufacturers to ll in 39data gaps39 for older products by 1997 to determine Whether they should be reregistered Since the reregistration requirement was enacted several products and certain uses for products have been voluntarily discontinued by manufacturers because of the time and cost requirements for reregistration are too high to justify the costs of lling in the 39data gaps39 required for reregistration The Future I Industry is constantly looking for new modes of action I New modes of action are needed To develop safer products Control speci c pests Resistance Herbicide Classi cation Herbicides can be classified several different ways Toxicity general vs restricted use Selectivity selective vs nonselective Method of Application preemergence vs postemergence applied Period of Residual Activity residual vs nonresidual Chemistry Mechanism of action Herbicide Classi cation General and Restricted Use The Federal Environmental Pesticide Control Act FEPCA was enacted in 1972 as an amendment to FIFRA and requires that all pesticides be classi ed as either generaluse or restricteduse pesticides A second component of FEPCA requires that anyone applying restricteduse pesticides be certified by the state in which he or she lives or intends to make the application A herbicide is a generaluse pesticide if the registration data provided by the manufacturer to the EPA indicate that it poses no unreasonable risk to the environment and is safe for use Mechanism of Action Photosynthesis Inhibitors Pigment Inhibitors Cell Membrane Disruptors and Inhibitors Cell Growth Disruptors and Inhibitors Cellulose Biosynthesis Inhibitors Lipid Biosynthesis Inhibitors Amino Acid Synthesis Inhibitors Unknown Chemistry 39 F OPS and DIMS Aryoxyphenoxy propionates and cyclohexanediones IMIs and SUs Imidazolinones and sulfonylureas s triazines Herbicide Selection Herbicide Use Herbicide 3 Control Application Evaluation Herbicide Selection There is no Silver Bullet Is the herbicide economical to use Control provided must exceed the cost of leaving the weeds alone Individual practitioners set thresholds according to need Are there environmental dangers from the herbicide use Herbicide Selection Will the herbicide adequately control the weed species present Is the crop suf ciently tolerant of the herbicide What are the rotational plans What is the danger to nontarget plants Is the soil suited for the herbicide choice Timing of postemergence herbicide application In Boo hardl red spring wheat durum and barleyquot Final 1339 3 la 4 Lani 5 Lea 113 line 240 39 My v HERA r Bmmuxynil my 24 E Mlv w 24339 8amper Iumter MCF A 013mm lama31 24 D rrter quot D EarrueL39SGF A3331 avenge Earnel39SGF A iniCF39A Bana ell39SGF a Evil Emmox39 nil Br moxynll MEPA Camas v WCF A or Bmmnx anil Clams 2quot D CEI NEIS 2 L BarrMJSG39F Cheyenne Bung Dakota E1 WP nr Emmmxynil EIDTESo 24 Expr MD Sam Flngssa MCF Am Bromuxynll Finesse 240 Finfe 2 d D Ea Harmorrf Extra MCPA Enzmoacynii Han nm rp Exlra MD IIarrrm39 Exlra 231D SawgSG Hoa n Hogan Brnmuxwil PDI 4 Ag V Ma 49quot m LHQHJ Crop removal Topsoilt 1 39 39 39 r HBHB B 39 Adsorptlo K N a DGHB HB Subsoil Parent material Water table Herbicide Fate in the Environment Atrazine Samples Above Allowable Level Danville IL 88 Ft Wayne IN 36 Bowling Green OH 38 Columbus OH 43 Kansas City KS 44 A Decatur IL 63 vmmg III the Topeka KS 38 m quot Indianapolis IN 50 quotquot quotmums Omaha NE 31 of Balms Richmond IN 13 Battleten Lawrence KS 22 Egg JE erson City MO 14 trommrazinein Springfield IL 15 IanWaier New Orleans LA 25 In summary Herbicides offer considerable labor reductions and much greater efficacy over other methods In the past 30 years the EPA has made great strides in increasing the safety of herbicides We should not be solely reliant on herbicides Cultural biological and mechanical methods should be incorporated whenever possible in an integrated control strategy Renewable Agriculture and Food Systems 222 80 85 doilOrlOl7Sl742170507001871 Preface Renewable Agriculture and Food Systems is a multi disciplinary journal which focuses on the science that underpins economically environmentally and socially susminable approaches to agriculture and food production The journal publishes original research and review articles on the economic ecological and environmental impacts of agriculture the effective use of renewable resources and quot in an and sociological implications of sustainable food systems It also contains an open discussion Forum which presents lively discussions on new and provocative topics However the opinions of the Forum and responses are solely those of the authors and do not necessarily re ect the opinions of Renewable Agriculture and Food Systems or Cambridge University Press John Wt Doran EditorinChief RAFS Can organic agriculture feed the world Catherine Badgley and Ivette Perfecto Forum The prospect that organic agriculture has the potential to feed the world is welcome news in light of the contra dictions of modern agriculturelr These include the massive productivity of greenrevolution agriculture yet the stub born persistence of hunger and malnutrition the loss of small farms even though they are more productive and contribute more to local economies than do large farmsz and the pervasive environmental destruction by agricultural biocides and synthetic fertilizers even as more and more ecological services of agricultural landscapes are being recognized r Organic agriculture per se cannot resolve all of these contradictions but its potential to provide enough food to feed the entire world opens the door to the creation of a new kind of food system based on agroecological production principles We Badgley et all in this issue have demonstrated two critical points The rst is that the relative yields of organic versus nonorganic methods greenrevolution methods in the developed world low intensive methods in the developing world suf ce to provide enough calories to support the whole human population eating as it does today This conclusion is based on a global dataset of 293 yield ratios for plant and animal production The second point concerns nitrogen fertilityr Data from 77 published studies suggest that nitrogen xing legumes used as green manures can provide enough biologically xed nitrogen to replace the entire amount of synthetic nitrogen fertilizer currently in user Thus the principal arguments from critics of organic agriculture are invalid These results are controversial partly from prejudice and vested interests in the current agricultural system and partly from disputed aspects of the analysis While this study claims that organic yields and nitrogen fertility methods could feed the world it does not forecast yields for any particular crop or region nor does it claim that a global organic food system would necessarily increase food security anywhere Food security depends on policies and prices as much as on yields Our study is not the only one to reach this conclusion In 1990 Stanhill4 came to a similar conclusion about organic production based on a compilation of data from North America and Europe Gris average yield ratio was the same as ours for the developed world More recently Halberg et all5 modeled scenarios of conversion to organic agriculture in Europe North America and subSaharan Africa using a globalized market model They concluded that largescale conversion to organic agriculture would not severely diminish either the global food supply or food security in developing regions They noted that food policies favoring local food availability rather than export crops would enhance the impact of conversion to organic farming and increase food security in subSaharan Africa Reviewers raised issues that merit dialogue beyond the context of the article The rst issue concerns the differences in cropromtion patterns between organic and conventional grain agriculture The second concerns the reliability of different kinds of sources ire peerreviewed versus gray literature for agronomic datar Rotation effect Organic grain production frequently uses a different rotation cycle than conventional product ion This difference complicates the comparison of yields 2007 Cambridge University Press Forum between organic and conventional systems without some nd of time adjustment for grain that must be grown in a longer rotation cycle by organic methods Corn wheat and rice the world s staple grains are grown in approxi mately equal quantities in megagrams on a global basis6397l In the US corn and wheat are usually grown in rotationgl Corn is typically grown in a longer romtion under organic than conventional methods For wheat it is not clear that organic and conventional rotations differ in length Most rice is grown in irrigated elds so tailored to rice production that other plant crops are not usually included although green manures and animals can be included organic and conventional methods for rice do not require different rotations Thus corn is the main crop for which the rotation effect is an issue A survey of cornother crop romtions from the sources of yield dam cited in Badgley et all1 this issue reveals that conventional corn was grown 25 60 of the time in rotations of 2 6 years and organic corn was grown 25 50 of the time in romtions of 2 4 years For the sake of a quantitative example we can determine the yield adjustment for two widely used rotations of corn a 2year rotation of corn soybeans under conventional management and a 3year rotation of corn soybeans wheatcover crop under organic management All other things being equal the organic system would produce only 67 as much corn as the 2 ear conventional system would If we multiply all of the individual yield ratios for corn in our dataset for the developed world by 067 and then recalculate the average yield ratio for grains the result is 084 instead of 093 The reduction in caloric output from the lower average yield ratio for grains in the developed world results in a change from 2641 to 2523 total kcal person 1day 1 in Model 1 based on yield ratios from developed countries and from 4381 to 4358 total kcal person 1day in Model 2 based on yield ratios from developed and developing countries Even with this time adjusted correction for corn both models generate enough calories ire gt2500kcal person 1 day 1 to feed the current population These calculations are conservative since many conventional rotations feature corn less than 50 of the timer Organic rotations are capable of sustained production of grains rotated with other crops as demon strated by the Rodale Farm Systems Trial A more thorough evaluation of rotation effects requires quantitative comparison of the plottoplot yield differences between organic and conventional production and the rate of change in both organic and conventional production methods as a function of the rotation sequencer Thus the necessity for different rotation schedules would decrease the production of corn But since over production of corn has depressed the price of corn for many years this change could actually bene t farmers economicallyl Gray literature A reviewer raised the concern that our quantitative results were suspect because a number of our yield ratios come from the gray literature Actually 81 74 of the studies included in our analysis are from peerreviewed journals For a study of this sort which makes a globalscale analysis it is impormnt to include as many studies as possible from as many regions as pos sible We included studies of three kinds controlled experiments of two or more management methods pairedfarm comparisons in regions with the same soils and climate and comparisons on the same farm before and after a change in management practices All three kinds of studies could be found in both peerreviewed and grayliterature sources It is worth noting that some grayliterature sources are quite reliable such as the tech nical reports of respected agricultural experiment stations the Henry Wallace Experiment Station Maryland Kel logg Biological Station s LongTerm Ecological Research Site Michigan the Organic Farming Research Found ation California Three published works that we con sulted for dam also cited a mixture of peerreviewed publications gray literature and personal communications Stanhill s4 compilation is largely supportive of organic farming while McDonald et all10 which focuses just on the system of rice intensi cation was skeptical The third source was the book by Lampkin and Padel which cites a similar range of sources for yield information The point is that our compilation is not unusual in the kinds of sources used for analysis The most problematic source from the reviewer s smndpoint was the report by Pretty and Hine12 based on survey data from 52 developing countries Yields were compared before and after farmers adopted speci c agroecological practices An analysis based on dam from this report was subsequently published in Agriculture Ecosystems and Environment l T e main reason for including many of the quantitative comparisons in this report is that relatively few published studies are available from farms in the developing world In order to evaluate whether the survey dam biased our results for the developing world we performed a signi cance test on the survey data compared to data from experiments and paired farms The test failed to reject the null hypothesis that the means in yield ratios do not differ signi cantly This test is explained in detail in Appendix 1 of Badgley et all We concluded that the use of survey data from the report of Pret and Hine12 did not unduly bias our results for the developing world We note however the need for more quantitative experimental comparisons in developing countries One controversial management practice is the system of rice intensi cation SRI in developing countries Its proponents claim that it boosts yields substantially while its critics argue that bestmanagement conventional pract ices perform just as well A reviewer commented that our cited publications on SRI did not provide the minimum information about soil and environmental conditions for the sites where the studies were performed This criticism applied to some of the studies cited on both sides of the debate We tried to avoid bias by using data from both 82 proponents and critics in the debate Furthermore global estimates by de nition involve generalities Detaile information about soils climatic conditions and speci c management practices was not given for all the studies regardless of publication source In principle these unmeasured variables would favor yields in the conven tional system in some instances while in others they would favor the organic system There is no reason to think that the lack of information about these variables would bias our study in any particular direction In general we recognize that the high yield ratios from developing countries likely result from the fact that many existing farming practices do not involve optimal amounts of synthetic fertilizer and may not be managed optimally in numerous other ways The adoption of organic methods in these settings is a huge improvement However our aim is not to demonstrate the superiority of organic farming over conventional agriculture Our aim is simply to investigate whether organic agriculture can produce enough foo to feed the world s population ours is a suf ciency argu ment It is appropriate to use yields from suboptimal existing systems in developing countries because these systems are representative of much of the developing world and most of the world s farmers Going forward Readers of this journal are well aware of the achievements of alternative agricultural systems both agronomically and economically These achieve ments would multiply with additional research on locally suitable cropping systems fertility methods and pest man agement for different agricultural regionsi Changes in agricultural policy are essential and could foster changes in farming and marketing practices within a few years As an example the Cuban food system underwent mas sive reorganization of farming and marketing methods after the fall of the Soviet Union in 1990141 After a few years of crisis exacerbated by the US economic blockade Cuba now has one of the most progressive food systems in the world A global food system based on agroecologi cal principles is possible and there are urgent reasons to move in this direction References 1 Badgley C Moghtader J Quintero E Zakem E Chappell MJ Aviles Vazquez K Samulon A and Perfecto I 2007 Organic agriculture and the global food supply Renewable Agriculture and Food Systems 22286 108 2 Rosset P 1999 The multiple functions and bene ts of small farm agriculture in the context of global trade negotiations Food First Policy Brief No 4 Forum 3 Daily GC Alexander SE Ehrlich PR Goulder LH Lubchenco J Matson PA Mooney HA Postel S Schneider SH Tilman D and Woodwell GM 1997 Ecosystem services bene ts supplied to human societies by natural ecosystems Issues in Ecology 21 18 i1 9 The comparative productivity of organic Agriculture 4 agriculture Ecosystems and Environment 5 Halberg N Alroe HF Knudsen MT and Kristensen ES eds 2005 Global Development of Organic Agriculture Challenges and Promises CAB International Wallingford UK Clay J 2004 World Agriculture and the Environment Island Press Washington DC Food and Agricultural Organization of the United Nations 2003 FAO Statistical Database Available at httpfaostat faoorg Vesterby M and Krupa KS 1997 Major land uses in the United States Economic Research Service US Department of Agriculture Statistical Bulletin No 973 Pimentel D Hepperly P Hanson J Douds D and Seidel R 2005 Environmental energetic and economic comparisons of organic and conventional farming systems BioScience 55573 582 McDonald AJ Hobbs PR and Riha SJ 2005 Does the system of rice intensi cation outperform conventional best mana ement A synopsis of the empirical record Field Crops Research 9631 36 Lampkin NH and Padel S eds 1994 The Economics of Organic Farming An International Perspective CAB Inter national Wallingford UK Pretty J and Hine R 2001 Reducing Food Poverty with Sustainable Agriculture A Summary of New Evidence Final report from the SAFE World Research Project University of Essex Available at httpwww2essexacuk htm CR 1 00 o H O H H H to accessed 22 February 2007 Pretty JN Morison J IL and Hine RE 2003 Reducing food poverty by increasing agricultural sustainability in developing countries Agriculture Ecosystems and Environ ment 95217 234 World Resources Institute 2000 World Resources 2000 2001 World Resources Institute Washington DC H L H 4 Catherine Badgley is a research scientist with the Department of Geological Sciences and the Museum of Paleontology at the University ofMichigan Ann Arbor MI Ivette Perfecto is a Professor in the School of Natural Resources and Environment at the University of Michigan Ann Arbor MI USA Note Catherine Badgley and Ivette Perfecto have not had an opportunity to respond to the following comments by Kenneth Cassman and Jim Hendrixi Forum Editorial response by Kenneth Cassman can organic agriculture feed the world science to the rescue During the past 30 years there has been a steady decrease in nding allocated to agricultural research in both developed and developing countries because of the widespread view that food insecurity is primarily caused by poverty and a lack of purchasing power rather than the inability to produce enough foodll However these views are being challenged by three global megatrends l a steady decrease in arable land area suitable for intensive food crop production as a result of farmland conversion to urban industrial and recreational uses 2 a steady reduction in the relative rate of yield gain for the major cereal crops yield gains that are falling below the projected rate of increase in cereal demand and 3 a recent acceleration in the expansion of biofuel production from cereal sugar and oilseed crops that will divert signi cant amounts of these crops from the human food supply l Given these trends the question of whether organic agriculture can meet current and future food demand at national and global levels is serious business especially if the answer in uences funding priorities for agricultural research4395l Unfortunately the paper by Badgley et all6 and the associated forum paper by Badgley and Perfecto both in this issue of RAFS Volt 22 Not 2 do not answer this question because their analyses do not meet the minimum scienti c requirements for comparing food production capacity in different crop production systems Scienti c progress depends on published research in peerreviewed journals journals that require detailed speci cation of materials and methods used in the study to allow other scientists to challenge the conclusions and if necessary repeat the A For L of cropping systems with different management strategies the following speci cations and dam are required 1 De nition of the systems to be compared For example is the goal to compare or anic and conventional systems when both utilize the best available technologies and crop rotations for a given eld and region In this case researchers must strive to identify best management practices that optimize performance of each system separately with regard to input levels and timing of all crop and soil management operations for the speci c soil and climatic conditions at the research site In contrast most comparisons of organic and systems utilize a relatively customized set of practices for the organic system and standard recommended practices for the conventional system or practices thought to represent average practices used by conventional crop producers in the region The problem is that most conventional crop producers also customize crop and soil management practices to their production environment which can vary subsmntially from eld to eld Hence a bias exists unless both systems receive the same degree of concern for optimization of all crop and soil management practices for a given site within the general guidelines of practices allowed for organic versus conventional systems i Speci cation of performance parameters as the basis of comparison The most relevant parameter to address the question of food security is food output per unit area time The time dimension is critical because organic systems often require rotations that include nonfood crops such as legume cover crops or loweryielding legume crops to provide nitrogen input from symbiotic nitrogen xation While yield of the same crop species grown in organic and conventional systems may be similar total food output of the cropping system may differ depending on the rotation Further speci cation of human edible calorie andor protein yield per unit area time is also helpfull Quantifying nutrient input levels and equalizing them as required Organic systems typically rely on manure or compost to satisfy crop nutrient demand and to maintain soil fertility But release of organically bound nitrogen N phosphorus P and sulfur S in manure depends on biological processes controlled by temperature moisture and microbial activity In fact only a portion of the applied nutrients contained in manure are released during the growing season in which the manure was applied Likewise the total amount of nutrients applied in manure is usually much greater than toml nutrients applied in conventional systems receiving recommended rates of commercial fertilizer Over time the indigenous soil nutrient supply in organic systems often increases compared to that of conventional systems receiving 39 39 fertilizer ratesl Moreover manure con mins all essential plant nutrients in addition to N P and K which are the primary nutrients applied in conven tional systems As a result researchers comparing conventional and organic systems must carefully monitor crop nutrient status to ensure that the conven tional system is not de cient in one or more essential nutrient because these de ciencies are easily corrected by application of the appropriate commercial fertilizer Such measurements are especially important when organic versus conventional comparisons are conducted on soils that do not have high indigenous fertility levelsl N E 5 pp p 39 r 39 39 design and treatment replica tion Modern statistical methods were initially develop ed in the rst half of the 20th century by agricultural scientists who recognized the challenge of making scienti cally sound conclusions based on results from eld experiments Spatial and temporal variation in soil properties and climate require use of statistical theory in experimental design treatment layout and replication Results from eld studies that do not adhere to accepted statistical norms are not reliable The above speci cations and data represent a minimum smndard for making reliable comparisons of different 84 cropping systems In my opinion many of the studies cited by Badgley et all6 fail to meet these standards Therefore it is not possible to make sweeping conclusions about the potential for organic systems to feed the world by simply comparing yields between organic and conventional systems Likewise even more stringent and comprehensive speci cations and data would be required for valid comparisons of the environmental impact of organic versus conventional systems including the impact on soil quality water quality as affected by nutrient losses and greenhouse gas emissions One cannot simply assume that organic systems are more environmentally sound because they do not use commercial fertilizers and pesticides In fairness to those who conducted most of the studies cited by Badgley et alts the conduct of scienti c studies of publishable quality does not appear to be their primary goal Many seem to be demonstrations and informal trials While such trials may have educational value they are not an appropriate basis for scienti c inquiry In conclusion the question of whether organic systems can feed the world remains unanswered Given the need to produce 60 more food by 2050 to meet demand from growth in both population and income and to do so with less land and water for irrigation there is an urgent need for a process of ecological intensi cation of crop production systems7r A focus on existing conven tional and emerging organic systems limits the possibilities Instead the emphasis should be on developing cropping systems that best contribute to a set of wellde ned performance parameters that ensure adequate food supply farm family income and protection of environmental quality and natural resources If a system meets these criteria it should not matter whether it complies with rules prescribed for organic production systems or any other arbitrary set of prescriptions for crop and soil management Forum The trend of decreasing funds for agricultural research in the public sector dicmtes a more ef cient approach one that focuses on outputs G3road sense including environ mental impact from agricultural systems rather than on the type or source of inputs References l Dreze J and Sen A eds 1989 Hunger and Public Action Clarendon Press Oxford UK Cassman KG Dobermann AD and Walters DT 2002 Agroecosystems N use ef ciency and N management AMBIO 31132 140 to L Council for Agricultural Science and Technology CAST 2006 Convergence of Agriculture and Energy Implications for Research and Policy CAST Commentary QTA 2006 3 CAST Arnes IA Cassman KG 2001 Crop science research to assure food security In J Nosberger HH Geiger and RC Struik eds Crop Science Progress and Prospects CAB International Wallingford UK p 33 51 Tilman D Cassman KG Matson PA Naylor R and Polasky S 2002 Agricultural sustainability and intensive production practices Nature 418671 677 Badgley C Moghtader J Quintero E Zakem E Chappell MJ Aviles Vazquez K Sarnulon A and Perfecto I 2007 Organic agriculture and the global food supply Renewable Agriculture and Food Systems 22286 108 Cassman KG 1999 Ecological intensi cation of cereal production systems yield potential soil quality and precision agriculture Proceedings of the National Academy of Sciences USA 965952 5959 4 Ln CR 1 Kenneth G Cassman is the Director of the Nebraska Center for Energy Sciences Research and the B Keith and Norma F Heuermann Professor ongronomy at the University of Nebraska Lincoln NE USA Editorial response by Jim Hendrix Farming looks mighty ears when your plow is a pencil and you re a thousand miles from the corn eld Dwight D Eisenhower When Eisenhower made the above observation in 1954 our nation was one to two generations removed from the realities of farming In the intervening 53 years certain segments of our society have come to idealize agriculture with a desire to connect to smallscale organic familyoperated farms and to demonize largescale com mercial farms Organic agriculture and the global food supply by Badgley et all exempli es the perspective of some scientists in the academic world who favor organic practices without having a grounded knowledge of the economics and drivers of food production I am a largescale crop producer in the high plains region of Colorado Kansas Nebraska and Texas We utilize center pivot irrigation on coarse sands practice integrated pest management and are early and consistent adaptors of technology to substitute capiml for laborr We operate several farms utilizing conventional inorganic fertilizers pesticides crop romtion and minimal tillage to produce corn edible beans and alfalfar I am also involved with a largescale organic farm and dairyfeeding operation in which we grow grain and alfalfa to produce organic milk This combination of production practices employing both organic and inorganic farming techniques gives me insight into production costs and problems associated with both systems The Badgley et al article misses the mark in several critical areas In production agriculture farmers respond to market signals and nitrogen is just one considerationr Organic fertilizer bene ts are measured based upon N content and in some cases the content of other nutrients Forum However these nutrient additions are worth only the sum of their parts organic nutrients convey no magical proper ties Because economics drive production all sources of nitrogen will be used in the production of food and combinations of organic and inorganic nitrogen are often used on the same farmt Likewise the decision to include legumes in a crop rotation is made to maximize economic return and is based upon longterm fertility current pro tability availability of labor and management market ing opportunities and a host of other factors I question the validity of the statement that production per unit area is greater on small farms than on large farms Large farms generally maximize land labor machinery and management to lower the unit cost of the commodity being produced Over time commodities always trade at the average cost of production leaving little room for producers who are high cost due to low volume It is elitist to condemn people to the drudgery of hand labor required on small organic farms only those who have never done such work believe it is an employment solution Throughout history farm producers have sought product ivity gains by substituting animal for human labor designing and employing simple machines and most recently using information technology remote monitoring and sophisticated machineryt It is unreasonable to believe that agriculture will return to hand labor to reduce unemployment or underemploymentt The nal fallacy in the Badgley et al article is the insinuation that organic farming is an advanced method of crop production that always leads to better soil tilth less erosion and superior nutrition In our experience organic corn requires soil tillage prior to planting and cultivation during the growing season to control emerging seedling weeds These operations destroy organic matter reduce the waterholding capacity of our light sands and increase soil susceptibility to wind erosion In contrast our transgenic corn is planted into winter cover crops which are killed with herbicides after planting Later developing weeds are controlled with additional herbicides instead of mechanical cultivation These conventional farming practices allow us to maintain a protective residue cover on the soil surface and increase soil organic matter inputs As a largescale producer of organic and conventional food products I would like to share a few insights into the crops that we produce Generally speaking as we move into more specialized crops and end products organic farming becomes more dif cult and expensive For example there is little difference in the cost of production or yield between organic and inorganic alfalfa Insect and weed pressures are generally controlled with an early harvest although this may change with new transgenic alfalfas that offer a longer smnd life On the other hand dry edible beans are dif cult to grow organicallyt They do not compete well with weeds 85 and are subject to bacterial fungal and rust infections and insect infesmtions which can cause considerable loss in both quantity and quality Furthermore organic bean yields are typically less than half of those for conventionally grown beans The primary consumers of dry edible beans are generally unwilling to pay for the higher cost of organic production Production issues for organic corn fall somewhere between those for alfalfa and dry edible beans Producers can access the highest yielding nontransgenic hybrids In organic corn production our limiting factor has not been nitrogen or other crop nutrients even though total fertility costs are about 40 higher when compared to inorganic forms of fertilizers Rather soil insect pressure during stand establishment and the effective control of insects during the growing season have reduced organic corn yields to 80 85 of conventional Overall our cost per unit of production has been approximately 30 higher for organic compared to conventional cornt In our operations the economic driver for organic corn has been the production of a feed source for organic milk Additional costs associated with organic production have been borne to date by the marketplace where wholesale organic milk is currently over twice the price of conven tional Consumers of organic milk believe there is economic and nutritional value in their purchase Yet using the latest advances in laboratory testing we have been unable to demonstrate any difference in the nutrient content between our organic and conventionally produced milkt By purchasing organic milk and other organic products I also believe that consumers feel they are supporting the idealized image of a smallscale organic familyoperated business This is rarely the case Although economics will dictate how long we produce organic milk we question the morality and sustainability of organic production Given its inherently higher cost are families purchasing less milk to the detriment of young children Would these children be better served with larger quantities of nutritionally equivalent conventional milk The same questions can be asked with regard to organic fruits and vegetables In e developed world of agriculture producers respond to market incentives Given suf cient net returns to attract adequate capital and management producers will industrialize the production of organic food We are not driven by ideological concepts political correctness or environmental persuasions we are driven by the market place Farmers always respond to incentives in the market and will produce suf cient food using combinations of conventional and organic methods to maximize their individual net returns Jim Hendrix is a farmer and President of Progressive Ag Management Inc Wray CO USA
Are you sure you want to buy this material for
You're already Subscribed!
Looks like you've already subscribed to StudySoup, you won't need to purchase another subscription to get this material. To access this material simply click 'View Full Document'