Iowa Crop Variety Yield Testing: a History and Annotated Bibliography Lorraine J

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6-16-2017 Iowa Crop Variety Yield Testing: A History and Annotated Bibliography Lorraine J. Pellack Iowa State University, [email protected]

Douglas L. Karlen United States Department of Agriculture, [email protected]

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Abstract Variety testing by U.S. agricultural universities, often in cooperation with experiment stations, and professional crop associations is recognized as an independent, unbiased validation of the viability of commercial crop varieties. In Iowa, variety testing has also been conducted by many private agricultural companies and individual farmers. Records for crop variety evaluations within the state can be traced back to 1871, well before the creation of the Iowa Agricultural Experiment Station in 1888. The oI wa Corn Yield Test (ICYT) is undeniably the most famous of the Iowa variety yield trials; however, corn (Zea mays L.) varieties were being tested long before that program was initiated. Furthermore, Iowa researchers have been conducting variety yield tests on many other field crops. Knowledge of how Iowa variety tests have been organized and published could be helpful to researchers looking for similar, long-term evaluations from other states and around the world. Variety tests from the past also have the potential to help guide new research efforts and may provide an important untapped resource for unique varietal data. As crop scientists and agronomists look to find new sources for biofuels, bio-products, and other industrial uses for various crops, data from historical varieties could be useful. The bjo ective for this review is to provide an historic account with sections on varietal testing in Iowa. It is presented in chronological order followed by sections devoted to specific crops. A Supplemental Information file containing a detailed annotated bibliography is also provided.

Keywords ICYT, Iowa Corn Yield Test

Disciplines Agriculture | Library and Information Science

Comments This article is published as Pellack, Lorraine J. and Douglas L. Karlen. “Iowa Crop Variety Yield Testing: A History and Annotated Bibliography.” Crop Science, 57, no. 4 (2017): 1-15. doi:10.2135/cropsci2017.01.0009. Supplemental Information file containing a detailed annotated bibliography is also provided. See link at the bottom of this page.

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This article is available at Iowa State University Digital Repository: http://lib.dr.iastate.edu/refinst_pubs/69 Published online August 28, 2017

REVIEW & INTERPRETATION

Iowa Crop Variety Yield Testing: A History and Annotated Bibliography

Lorraine J. Pellack* and Douglas L. Karlen

L.J. Pellack, Science & Technology Dep., Iowa State Univ. Library, ABSTRACT 150 Parks Library, Ames, IA 50011-2140; D.L. Karlen, Research Variety testing by U.S. agricultural universities, Soil Scientist, USDA-Agricultural Research Service, National Lab. often in cooperation with experiment stations, for Agriculture and the Environment (NLAE), 1015 N University and professional crop associations is recognized Boulevard, Ames, IA 50011-3166. The U.S. Department of Agriculture as an independent, unbiased validation of the (USDA) prohibits discrimination in all its programs and activities on the viability of commercial crop varieties. In Iowa, basis of race, color, national origin, age, disability, and where applicable, variety testing has also been conducted by many sex, marital status, familial status, parental status, religion, sexual private agricultural companies and individual orientation, genetic information, political beliefs, reprisal, or because farmers. Records for crop variety evaluations all or part of an individual’s income is derived from any public assistance within the state can be traced back to 1871, program. (Not all prohibited bases apply to all programs.) Persons well before the creation of the Iowa Agricultural with disabilities who require alternative means for communication Experiment Station in 1888. The Iowa Corn Yield of program information (Braille, large print, audiotape, etc.) should Test (ICYT) is undeniably the most famous of contact USDA’s TARGET Center at (202) 720-2600 (voice and TDD). the Iowa variety yield trials; however, corn (Zea To file a complaint of discrimination, write to USDA, Director, Office mays L.) varieties were being tested long before of Civil Rights, 1400 Independence Avenue, S.W., Washington, DC. that program was initiated. Furthermore, Iowa 20250-9410, or call (800) 795-3272 (voice) or (202) 720-6382 (TDD). researchers have been conducting variety yield USDA is an equal opportunity provider and employer. Received 5 Jan. tests on many other field crops. Knowledge of 2017. Accepted 16 Apr. 2017. *Corresponding author (pellack@iastate. how Iowa variety tests have been organized edu). Assigned to Associate Editor Stella Kantartzi. and published could be helpful to researchers Abbreviations: ICYT, Iowa Corn Yield Test. looking for similar, long-term evaluations from other states and around the world. Variety tests from the past also have the potential to help his review project started with a simple question: Where were guide new research efforts and may provide an TIowa corn variety yield test reports published, particularly for important untapped resource for unique varietal the years prior to what is available online? In the process of delv- data. As crop scientists and agronomists look ing into the history of Iowa crop experimentation and publication to find new sources for biofuels, bio-products, practices, test results for many other crops were discovered and and other industrial uses for various crops, the project expanded to include all Iowa crop variety tests. It also data from historical varieties could be useful. became apparent that difficulties in locating older variety test reports The objective for this review is to provide an were not unique to Iowa. The purpose of this review is to provide historic account with sections on varietal testing a history of field crop testing in Iowa and to identify publications in Iowa. It is presented in chronological order followed by sections devoted to specific crops. and other sources of information that may contain useful yield test A Supplemental Information file containing a results for individual crop varieties. Crop variety trials have been detailed annotated bibliography is also provided. Published in Crop Sci. 57:1984–1998 (2017). doi: 10.2135/cropsci2017.01.0009

© Crop Science Society of America | 5585 Guilford Rd., Madison, WI 53711 USA This is an open access article distributed under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

1984 www.crops.org crop science, vol. 57, july–august 2017 conducted and results have been recorded and published in farmers make better-informed decisions that would ulti- Iowa for nearly 150 years. However, locating varietal yield mately lead to higher profitability. In later years, chemical information is often complicated by several factors includ- composition in addition to crop yield was quantified to ing: different types of yield reports; different types of tests or help increase industrial market demand for specific crops. contests; similar terminology with very different meanings; “Variety trials range from the initial studies involv- published reports disseminated in a somewhat scattershot ing small plots (single plants or single rows) to replicated fashion through Experiment Station, Extension, or USDA yield trials involving fairly large plots” (Petersen, 1994, p.2). publications; results in unpublished theses/dissertations or Petersen provides introductory information on the pros and university library archives; and, private company yield testing cons of specific types of variety trial experiment designs results which are generally proprietary and rarely distributed and devotes the remaining chapters to special problems in outside of the company. Current practice in most U.S. states trials such as perennial crop trials, on-station vs. off-station is to provide performance trial reports online each year. Typ- trials, pasture trials, and intercropping research. ically, websites only provide reports for the most recent years While there are many reasons for differences in crop and the most popular crops. yields, even those grown under nearly identical condi- In the last 80 years, the literature of crop science has tions, early experiment designs eliminated as many vari- focused almost exclusively on breeding hybrid varieties, pri- ables as possible. From the very beginning, accuracy marily to increase crop yields and profitability for farmers. and repetition were considered to be “absolutely neces- Agronomists conduct crop experiments, record detailed data sary” and essential as well as making allowances for error in field notebooks, and then summarize results as part of (Convention of Friends of Agricultural Education, 1967, published journal articles. Unfortunately, the detailed exper- p.36–37). For information on the history of experimental iment results from individual studies have been relegated to design, replication and statistical analysis in varietal testing the filing cabinet and/or published in reports with limited the reader is referred to LeClerg et al. (1962, p. 105–136). distribution. The raw data also occasionally forms the basis Variety yield test publications vary in the level of detail of graduate student theses and dissertations (again, limited provided on experimental methods. They were often a distribution and not included in indexes to agronomy lit- simple summary; however, some researchers also supplied erature). As researchers retired, their files were discarded or in-depth plot design, replication, and harvesting informa- left behind for the next researcher to use. On occasion, the tion. Hitchcock (1921) summarized experimental meth- files were donated to a university archive. Historic accounts ods used at the Iowa Agricultural Experiment Station for traditionally give an overview rather than details of specific small grains and corn and then also compared Iowa meth- crop experiments. The two main publications summarizing ods to those in use at other U.S. stations at the time. U.S. field crop variety experiments (Fehr, 1984; Smith et al., It should be noted that not all crop yield publications 2014) focused exclusively on the impact of genetic improve- contain varietal information. One example is farm valua- ments. Only a few of the chapters included information on tion studies which depend primarily on soil productivity varieties prior to hybrid development and performance trial and crop yield. Traditionally, soil productivity evaluations reports were rarely included in the chapter references. In were based on yield estimates that were fairly subjective and addition, since their goal was to summarize yield develop- varied widely, thus resulting in land appraisals that were ments for specific crops, very little information was provided very inconsistent. Starting in the mid-1930s, data from crop on experiments at individual localities. yield tests began to be used as a measure of soil productivity (Huddleston, 1984, p. 301–305), but for those studies, What are Crop Variety Trials? the specific crop variety was neither tested nor considered Within this article, the phrase “variety yield tests” refers relevant. Instead, yield tests used for farm valuations looked to field experiments where different crop varieties were closely at soil types, depth of topsoil, and slope. grown and evaluated primarily for yield, but sometimes for many other important characteristics (e.g., disease What Initiated Individual Variety Testing resistance, lodging resistance, emergence characteristics, in the United States? growth and development rates, etc.). The test results were Varietal experiments were a large part of discussions pre- generally used to alert local farmers to best management dating the Hatch Experiment Station Act of 1887. The practices for growing specific crops and recommended Convention of Friends of Agricultural Education, held in varieties within specific geographic areas or on specific Chicago on 24–25 Aug. 1871, focused on three themes. types of soil. In addition to genetic differences, some of The first theme, which took up almost half of the meet- the historical tests also quantified the impact of other fac- ing transcript, and was clearly quite contentious, dealt with tors such as tillage, type of fertilizer, soil, or crop rotation experimental methods in agriculture (Convention of Friends on yields. In general, the original intent for developing of Agricultural Education, 1967). One of the Convention crop variety trials was to increase yield and thus help outcomes was Report of the Committee on Experiments, which

crop science, vol. 57, july–august 2017 www.crops.org 1985 outlined experiments they felt colleges should conduct. It 1937 they were clearly on the rise due to the increased use included “Experiments in special culture with different vari- of hybrid varieties (USDA, 1962, p. 19). eties of grasses, grains, roots, plants, trees, etc.” (Convention of Friends of Agricultural Education, 1967, p. 108). In the Iowa Varietal Testing early 1900s, as part of early meetings of the American Society Since the inception of organized crop variety testing, Iowa of Agronomy, there were numerous discussions of experi- Agricultural Experiment Station researchers, like their mental design and Wiancko (1907–1909, p. 29) asserted that counterparts in other U.S. states, have been continually “the all-around best variety of any crop can only be found developing and testing new crop varieties in each area and after repeated tests of all the varieties available.” Given the on different soil types within their states before recom- number of available varieties, this was no small task. mending or discouraging specific varieties to farmers. Iowa Using corn as an example, E.G. Montgomery speculated crop variety trials initially included experiments on all types that, there were “probably” about 1000 named varieties of of field crops being grown in the state. The ultimate goal corn and estimated that about three-quarters of them had was to increase farm profitability through a combination been developed since 1840 (Montgomery, 1913, p. 78–79). of higher crop yields, lower production costs and educa- Granted, many of these corn varieties were developed for tion opportunities for farmers so they could develop more specific geographic areas, climates, and/or soils around the successful soil and crop management practices and thus world; however, it illustrates the massive number of seed achieve greater crop yields. Over time, the focus shifted to choices available to farmers. There were 23 varieties of Dent experiments on the most profitable crops–primarily corn, corn principally grown in the Corn Belt (Bowman and oat (Avena sativa L.), and soybean [Glycine max (L.) merr.]; Crossley, 1908, p. 424–446). Reid’s Yellow Dent was one of however, Experiment Station researchers also continued to the most widely grown varieties, but even that variety had evaluate other field crops knowing that information would many strains developed and distributed by individual farm- also be useful for other agronomists and Iowa farmers. In ers. It did not take long for farmers to recognize that indi- the 1930s, hybrid oat production was a very time intensive vidual varieties had multiple characteristics that influenced process so efforts to significantly improve that crop were not not only yield but also composition and quality of the grain, sustained (Thompson, 1940). Corn and soybean became the and ease of harvesting. Therefore, as modern variety test- two main focal points for variety testing by Iowa research- ing programs evolved, valuable report information included ers. This was easily justified because they were the most planting and maturity dates, emergence characteristics, plant profitable for Iowa farmers to produce, and with the excep- growth, development and height, disease and insect resis- tion of a few periods when supply outstripped demand, tance, nutrient use efficiencies, lodging characteristics, grain markets for both have been fairly consistent. moisture content at harvest, and chemical composition. The Information on field crops produced in Iowa from 1866 composition measurements gradually led to further research to 1938 is available from Iowa Crop and Livestock Report- to quantify seed characteristics including protein, oil quan- ing Service (1938). Lists of specific crop varieties planted tity and quality, nutritional value, and other characteristics in Iowa from 1910 to 1929 are available in New Crop Vari- that could potentially influence other industrial uses. For an eties on Iowa Farms (Robinson, circa 1929). This provides example of how these ancillary studies make use of Agricul- yields and varieties for oat, wheat, barley (Hordeum vulgare tural Experiment Station variety trials, the reader is referred L.), corn, sorghum [Sorghum bicolor (L.) Moench], soybean, to Schwarte et al. (2006) and Weiss (1950). sudan grass [Sorghum sudanense (Piper) Stapf], hubam clover The success of individual varieties changed consid- [a unique varietal mixture of Melilotus officinalis and M. erably within every geographic region due to variations alba] and dalea [Dalea greggii]. Recommended crop variet- in soil types and climate zones. Any variety can produce ies distributed to Iowa farmers from 1912 to 1963 for oat, high yields within a specific area if growing conditions wheat, barley, soybean, corn, sorghum and forage crops and management practices are optimum, but even with are provided in The Story of the Iowa Crop Improvement Asso- the same management practices, yields can be much lower ciation and Its Predecessors (Robinson and Knott, 1963, p. in a different area of the county, state, or region. The suc- 130–131). As hybrid varieties were developed, and spread cess of a variety also depended on seed quality and crop out among a large number of seed developers, good sum- management practices. During the early 20th century, maries of available varieties became somewhat tricky to improved farming practices (primarily adding lime, P, and locate; however, additional varietal information can be K) increased productivity (i.e., yield per 0.41 ha [1acre]) gleaned from the Seed Directory published annually by the to a certain point for each type of soil, but after that, the Iowa Crop Improvement Association since 1909. emphasis shifted to crop breeding with a focus on achiev- ing greater yields by producing high-yielding varieties. As Results from Early Iowa Experiments a result, from 1910 to 1932, crop yields per 0.41 ha [1 acre]) The earliest record of Iowa crop variety experiments is across the entire nation remained virtually constant but by from 1871, pre-dating creation of the Iowa Agricultural

1986 www.crops.org crop science, vol. 57, july–august 2017 Experiment Station in 1888 by almost two decades. The researchers published journal articles with detailed methods Ninth Biennial Report for Iowa State Agricultural College and results from various crop experiments. includes information on 1.2 ha (3 acres) devoted to crop experiments. These were hardiness tests for specific variet- Corn Testing in Iowa ies. Crops included spring and winter wheat, rye, winter Early in the 20th century, plant breeders focused their oat, potato (Solanum tuberosum L.), and barley. It provides attention on corn as it was rapidly becoming the most prof- information on specific varieties planted and yields for each itable crop for Iowa farmers. Early corn varietal testing in (Roberts, 1872). Biennial Reports exist for earlier years, but the state focused on the importance of good quality seed, this was the first one to specifically include experimen- especially proper storage to prevent moisture in the seed tal information for field crops. The report also includes (Holden, 1905; Mosher, 1911). Later publications compared information from Charles E. Bessey (in the botany and test results on the optimum number of kernels planted per horticulture department), who tested varieties of potato, hill for maximum yield per 0.41 ha (1 acre) (Mosher, 1962a, tomato (Lycopersicon esculentum Mill.), cabbage (Brassica olera- p. 23–28), fertilizer types and rates, and planting dates. cea), beet (Beta vulgaris L.), and sweet corn. See True (1937) Perry Holden was hired by the Iowa State Agricultural for information on early experiments in other U.S. states. College in the fall of 1902. He had previously worked at In 1894, C.F. Curtiss began incorporating “Experi- Funk Brothers Seed Company in Illinois and was deter- mental Crop Notes” into the Bulletin–Iowa Agricultural mined to show farmers how to improve the quality of their Experiment Station each year. The report covered winter seed. Holden had conducted experiments to prove that poor wheat and root crops for stock. The 1895 report included corn yields were mainly due to bad seed. At a Sioux County winter wheat, oat, and corn. The 1896 report included Farmers’ Institute meeting (in northwestern Iowa) in Feb- those crops plus alfalfa (Medicago sativa L.) and potato. ruary 1903, farmers criticized Holden’s results as being not Information varied for each crop but included the number applicable to them because his tests were conducted in only of hectares planted, planting and harvesting dates, and one location, 200 miles away in central Iowa (Bliss, 1960, p. yields for each variety. 34). It was well-known that northern Iowa farmers needed In 1904, The Iowa Agriculturist published an article, aimed to plant an early maturing variety of corn due to the ear- at farmers, summarizing crop experiments being done by lier onset of cold weather. The result was the creation of the Iowa Agricultural Experiment Station (Anonymous, the Sioux County farm experimental plan (in cooperation 1904). The article describes experiments with corn breeding, with a group of farmers that attended the Farmers’ Institute) reducing oat smut (along with a recommended cure–forma- which was supported by County appropriations and land lin), a variety test with fall wheat, cowpea [Vigna unguiculata for the testing. The crop evaluations, conducted in coop- (L.) Walp.] varieties, and forage experiments including three eration with Iowa State College and the USDA, became the varieties of sorghum, five varieties of millet Pennisetum[ glau- first County Cooperative Extension work conducted in the cum (L.)] and 48 varieties of native and foreign grasses. Over- United States. These cooperative “Demonstration Farms” all, the information provided was very generic, but it did expanded rapidly to other areas of Iowa: 5 counties in 1904, include detailed information about eight varieties of cowpea 8 counties in 1905, and 10 in 1906 (Bliss, 1960, p. 36). being tested to determine which were best adapted to feed Holden became famous for establishing the Iowa Corn and which were better as fertilizing agents. Trains (also referred to as the Seed Corn Specials or the The examples given above are fairly typical examples Iowa Corn Gospel Trains) and organizing the first U.S. state of crop variety reports published during the early 1900s. extension service in 1906. All of these activities were initi- Most reports were aimed at Iowa farmers although others ated well before the passing of the Smith–Lever Act which were written for agronomists and researchers outside of established the Cooperative Extension Service in 1914. As Iowa. The name of a specific crop was rarely included in with the Farmers’ Institute presentations, Holden’s focus for the article or report title, because they summarized experi- the corn train demonstrations was on producing good seed ments for several different crops. Additional examples of corn (Bliss, 1960, p. 37–38; Holden, 1906, p. 20–21). The various crop experimental reports are presented in the Sup- Rock Island Railroad offered to run a special train with a plemental Information file for this article. Unfortunately, lecture car if Holden would give the talks. Common practice specific details regarding methods and results from those at the time was for farmers to save their best ears of corn, experiments are difficult, if not impossible, to locate. Some dry it, and store it to use as the following years’ seed; how- data may be found in early field notebooks contained in ever, sometimes there was still moisture within the kernels. the Iowa State University Library, Special Collections & The moisture froze in the winter and damaged some of the Archives Department (Allee, 1905–1908; Iowa Agriculture seed. This caused poor germination rates when planted in and Home Economics Experiment Station, 1931–ongo- the spring. Holden provided visible proof of this to farmers ing; Iowa Crop Improvement Association, 1902–ongoing; and taught them how to prevent damaged seed corn and how Mosher, 1899–1979). In later years, Experiment Station to test the seed. “The corn trains brought the work of the

crop science, vol. 57, july–august 2017 www.crops.org 1987 college before masses of farmers in a very effective manner” Corn Shows and Growers’ Contests (Bliss, 1960, p. 37–41). Instead of just lecturing to the farm- Growers’ contests are exactly what they sound like (i.e., ers, he brought charts and seed boxes and other illustrative organized events where farmers entered samples of their materials to visibly make his point. Prior to Perry Holden’s crops in contests with each other). There were many dif- corn trains in 1904 and 1905, farmers were “inclined to treat ferent types of contests over the years. The first in Iowa advice from the agricultural colleges with more or less con- were the “corn shows”, which were popular from around tempt.” The special railroad car method and demonstrations 1890 to 1920. Farmers entered their corn into contests used to educate farmers were “adopted by other states with that were designed to give a prize to the sample that “gave marked success” (Trigg, 1905). For more information on indications of having the greatest yielding power” (Wal- Perry Holden and the Corn Trains see “P.G. Holden and lace and Bressman, 1923, p. 199). Winning ears were the Corn Gospel Trains” (Sizer and Silag, 1981). In 1906, those which judges felt would produce the largest number after the Iowa Legislature enacted the Agricultural Exten- of shelled kernels, but they were judged based only on a sion Act making funds available for demonstration projects, visual examination of the ears. Wallace obliquely referred Martin Mosher (who was a student under Holden and served to corn show contests as beauty contests. as one of the lecturers on the corn trains in 1905) was put in In 1914, H.D. Hughes and Joe L. Robinson began a charge of conducting corn yield tests at various county farms systematic comparison of the yielding power of different in Iowa for Holden. Mosher went on to become the first strains of Reid’s Yellow Dent entered in the corn shows. county extension agent in Iowa (in Clinton County) in 1912. Unlike the corn shows, Hughes and Robinson grew the After leaving Iowa for a job in Illinois, Mosher established strains for 3 years under uniform conditions. They found corn yield tests in Woodford County, Illinois, in 1919 and yield differences of 1.2 Mg ha–1 (20 bushels to the acre) then campaigned to have these tests initiated by the USDA in among the various strains. This study was very striking many other Corn Belt states (Mosher, circa 1922). in that the results definitely showed that corn-show win- The first year ofstate-wide corn yield testing took place nings were not related to yielding capacity (Hughes and in Iowa in 1920 (Mosher, circa 1921, p. 1) with the establish- Robinson, 1929). Consequently, more and more emphasis ment of the Iowa Corn Yield Contest. “In the early years came to be placed on field performance tests rather than the test provided a means of locating high yielding variet- on physical appearance of the corn ears. ies and strains of open-pollinated corn. Later it served as a In spite of this shifting emphasis on performance tests, very excellent vehicle to demonstrate the advantages of good farmers continued to enter crop contests and the contests hybrids over open- pollinated varieties, and then to calling flourished for many years. Prize money could amount to as attention to the best hybrids” (Robinson and Knott, 1963, much as US$1500 a year and winning strains tended to result p. 64). Professor H.D. Hughes and Henry A. Wallace are in increased seed sales for those farmers. One such contest credited by many as being “largely responsible for starting for corn was the Iowa Master Corn Grower’s Contests (a.k.a. the Iowa Corn Yield Test in 1920” (Robinson and Knott, Ten Acre Corn Yield Contest–which was reduced to a 2.1 ha 1963, p. 64–65; Sprague and Cunningham, 1946, p. 36–37). [5 acre] contest in 1955). This was started by the Iowa Crop Hughes was in charge of the Experiment Farm Crops Station Improvement Association in 1938. These were locally spon- work and Wallace was active in the development of hybrid sored events (e.g., by local Farm Bureau offices) in which the corn and the promotion of good farming practices. Hughes winning entries were submitted to the district-level contest became famous for inventing the rag-doll seed tester and the and then to the state level. They originated as an attempt clover-seed scarifier, he discovered annual white sweetclo- to establish uniform requirements for local and county con- ver (Melilotus alba Medik.), and found a way to dry corn in tests on a state-wide basis. A problem had arisen due to each the crib. Rather than patenting any of these things, he chose group developing their own regulations. “As a result vari- to give them to America’s farmers (Gregg, 1922). Henry A. ous claims were made for the highest yield, but generally Wallace1 published numerous articles and editorials in his the requirements under which they were produced varied to family’s newspaper, Wallace’s Farmer, which was widely dis- such an extent that yields between groups were not compa- tributed and read throughout the Midwest. He also devel- rable” (Robinson and Knott, 1963, p. 48). Variety informa- oped a high-yielding hybrid in 1924 that was the first hybrid tion was inconsistently recorded in the early years and was to win a gold medal at the Iowa Corn Yield Contest. Real- later dropped from the entry form altogether. Two attempts izing there was no place for farmers to buy hybrid seed, Wal- were made to study the contest data and try to determine the lace founded the first hybrid corn company in Iowa in 1926. causes for the highest yields, but there was too much inaccu- This became the largest hybrid seed company in the world, racy and not enough detail to draw conclusions (Robinson now known as Pioneer Hi-bred Corn Company. and Knott, 1963, p. 56–57). Raw data from these contests are available in the Iowa State University Library, Special Col- 1 Henry A. was the third Henry Wallace in his family. He was the most lections and University Archives Department (Iowa Crop famous of the three. Both Henry A. and his father (Henry C.) served as U.S. Secretary of Agriculture. Improvement Association, 1902–ongoing).

1988 www.crops.org crop science, vol. 57, july–august 2017 Demonstration Farms and Variety Tests Farmers’ Variety Tests before 1910 Farmers’ Variety Tests for 1910 to 1916 can be found in As mentioned earlier, the first demonstration farm in Iowa Demonstration Farm Reports (Iowa State University Coopera- was established in 1903 in Sioux County, to test seed quality tive Extension Service, 1910–1916). These demonstrations and replicate Perry Holden’s seed corn experiments under took place on farms in about a third of Iowa’s 99 counties local conditions. The first demonstrations undertaken in (Mosher, 1962a, p. 31) and were almost exclusively corn Sioux County were what later came to be known as the variety tests. The 1913 Allamakee County report (Demon- Farmers’ Variety Test. They were planned as demonstrations stration Farm Report no. 45, published in 1914) was the first rather than experiments. In keeping with Holden’s farmer to cover oat (and only oat). Other atypical Demonstration education theme, each farm provided “field days” with orga- Farm Reports were: No. 51, Scott County–covered corn, nized programs for the public in the early fall of each year. potato, and alfalfa; No. 56, Blackhawk County–covered This gave farmers the opportunity to visit the plots, learn only oat; No. 59, Hardin County– covered corn and oat; about the experiments and ask questions (Mosher, 1962a, p. No.62, Clinton County–covered corn and oat. 16, 20–21). Corn variety testing was also being conducted at Demonstration Farm Reports included: Farmers’ Vari- the Iowa State Agricultural College before 1910. According ety Tests, Introduced Variety Tests, Thickness of Planting to a Bulletin published by P.G. Holden and widely circulated Tests, and Single Ear Tests. Other tests included in later to Iowa farmers in December 1905: years were: Depth of Planting Tests; Butt, Middle, and Tip Kernel Tests; and, Individual Ear Germination Tests. “Last Spring, the Agricultural Department secured Demonstration Farm Report no. 2 gives this description of seed from more than ninety different sources. The the Farmer’s Variety Test: corn was all collected from farmers living within a radius of 10 miles from Ames. To secure samples “This test was made to determine the relative of corn actually planted, the farmers were visited yields obtained from different men’s seed corn and the corn taken either directly from the planter when grown under uniform conditions. Samples boxes in the field or from the sacks which the seed of seed corn were obtained from 80 farmers in the corn was being planted” (Holden, 1905, p. 172–173). following manner. Men were sent throughout the county at planting time with instructions to obtain This sample collecting technique is nearly identical a sample of seed corn from every man whom they to that of the Farmers’ Variety Test procedures found in saw planting corn. It was also ordered that the sam- the Demonstration Farm Reports (see Farmers’ Variety Test ples be taken from the planter box or sack which section below). Holden does not provide any details as to contained the seed in the field, so that they would which varieties were tested, but summarizes the results accurately represent the seed planted by the farm- saying that the only real differences in the yields appeared ers in their own field. These 80 samples were taken to be due to difference in vitality of the seed, not the vari- to the county farm, planted in the same field, and ety. Holden also states in the “Condition of Seed Corn” treated nearly alike as possible.” section (Holden, 1905, p. 170) that: This process of collecting samples is nearly identical to “Last winter and spring more than 3300 samples of that of the ICYT and was clearly a predecessor to it; how- seed corn were sent to the Experiment Station at ever, none of the tests involving uniform planting condi- Ames to be tested. These samples came from every tions were conducted on a state-wide basis until the Iowa section of the state and were made up in each case Corn Yield Test was initiated in 1920. of 200 kernels taken from 100 ears, this giving a representative of each man’s seed. These samples Iowa Corn Yield Test were given a careful germination test.” Iowa Corn Yield Tests have been sought after by research- On pages 171–172, Holden provided details of the ger- ers (within the state as well as beyond Iowa borders) since mination test. Other tests he mentioned included: record Iowa was the first state in which this sort of yield testing of individual ears, corn planter test, and shrinkage experi- took place. They are the most complete tests and the vari- ments from 1898 to 1905. He also provided a table with ety results became even more important as hybrids were nine varieties and the rates of shrinkage for each variety developed. These concepts are touched on in multiple (p. 180). Again, these were very similar to what is avail- sources (Jenkins, 1936, p. 479, 481–482; Robinson and able from the Demonstration Farm Reports starting in 1910. Knott, 1963, p. 65; Sutch, 2008, p.7). Data from corn experiments during 1904 to 1911 are in Even though corn variety yield tests were being con- unpublished manuscripts (Mosher, 1962a). ducted in Iowa as early as 1883 most historical accounts and current publications point to 1920 as the first year of the ICYT. For example, 2015 was the 96th consecutive year of the Iowa corn tests according to the introduction of crop science, vol. 57, july–august 2017 www.crops.org 1989 2015 Iowa Crop Performance Tests–Corn. Confusion regard- • 1923–1934 were published as separate reports named Iowa ing the official “start date” is likely due to several slight Corn Yield Test Results for [year]. Short summaries of the wording changes in test reports and similarity with other corn variety test results for 1930/1931– 1933/1934 were tests at the time. The earlier corn tests were conducted also included in the Report on Agricultural Research from the at the Iowa State Agricultural College or only in a few Iowa Agricultural Experiment Station in those years. counties, they were not state-wide. In 1920, announce- • 1935–1938 in Bulletin/Experiment Station, Iowa State ments and results referred to the yield test as the Corn College of Agriculture and Mechanic Arts. Yield Contest sponsored by the Iowa Corn and Small Grain • 1939–1958 in Bulletin P/Agricultural Experiment Station, Growers’ Association. By 1923, the name was changed Iowa State College. to the Iowa Corn Yield Test (rather than Contest) to avoid • 1959–1968 in Bulletin P/Agricultural and Home Econom- confusion with other ongoing corn growing contests ics Experiment Station, Iowa State University around the state. According to the first page of the 1920 of Science and Technology. Corn Yield Contest report, the Iowa Corn and Small Grain • 1969 issued solely within the Pamphlet a.k.a. Pm series Association began the contest “to determine the highest as Pm-449. yielding corn in each section of Iowa.” The Association • 1970–1985 were co-published as part of the Miscellaneous did not intend to “replace or duplicate individual farm Bulletin series as well as Pm-481, 494, 523, 548, 580, and county tests by these state wide trials, but rather… 603, and 660. aid and supplement them” (Iowa Corn and Small Grain • 1986–1998 were published only within the Pamphlet series Growers Association et al., 1920–1967, p. 3). Like other as Pm-660. contests with farmer-supplied entries of crop samples: the • 1999–2005 were co-published in the Pamphlet series as Iowa Corn Growers Association (ICGA) charged an entry Pm-660 and also as a supplement to the Iowa Farmer Today. fee to each competitor; awarded premiums, ribbons, and • 2006-present are online at: http://www.croptesting.iastate. ribbons to the top yielders; and a trophy for the highest- edu/Corn/Reports.aspx producing corn in the state (Robinson and Knott, 1963, p. 64, 68). The difference between the ICYT and corn Most of the reports give a summary of recent year’s growers contests is that the ICYT seed was obtained from results, so even if the publication for a specific year is missing farmers, but grown under “absolutely uniform conditions or unavailable, the results can still be found by looking in a of soil, cultivation and other factors” (Iowa Corn and slightly newer test report. In addition to the published ICYT Small Grain Growers Association et al., 1920–1967). A reports, the raw data from 1920 to 1951 tests are available very detailed description of the fields, plots, planting and for use in the Special Collections and University Archives harvesting processes, including transportation difficulties Department, Iowa State University Library (Allee, 1901– to/from the fields by railroad for the Experiment Station 1969, Iowa Crop Improvement Association, 1902–ongoing; staff, their equipment, and the entrant seeds is included in Mosher, 1899–1979). These files give much more detail than The Story of the Iowa Crop Improvement Association (Robin- the annual test reports provide, but many are handwritten in son and Knott, 1963, p. 74–83). Robinson also describes pencil and have fold-out tables that are not amenable to scan- changes that occurred over the years in test policies as ning/digitizing. The raw data also provides lists of farmers, well as processes. Another, more detailed, description of their county, and varieties. The amount of detail available the corn yield test technique is available from Corn and varies for each year. A chart listing the types of information Corn Growing (Wallace and Bressman, 1923, p. 205) and that was recorded for each year of the ICYT from 1920 to includes a discussion of benefits and difficulties. 1962 is available in Robinson and Knott (1963, p. 88–89). Published reports of individual corn variety tests in As mentioned earlier, Pioneer Hi-bred has also been Iowa are available for 1892 to present with some gaps and heavily involved in corn hybrid development in Iowa. overlap. This includes: Their breeding program has been actively testing hybrid performance since 1924. Industry reports are often locked • 1892, 1895, and 1896: Bulletin (Iowa Agricultural Experi- up in proprietary company files, however, Pioneer Hi- ment Station), No. 16, 19, 32, 34. bred test results are available from two sources. Donald • 1904–1911– see Martin L. Mosher, 1962a and 1962b. Duvick, a long-time employee and plant breeder for Pio- • 1909–1915– see Demonstration Farm Reports. neer Hi-bred, published a series of comprehensive, detailed • 1920, 1921, 1922– Iowa Corn Yield Contest (published as articles cumulating results from corn performance trials of separate reports). The results of the 1920 and 1921 contest hybrids released by Pioneer Hi-bred from 1930 to 2000 were also reported in a thesis: (Duvick et al., 2004). A later publication by several other Foiles, L.E. 1922. A Study of Strains of Corn Entered in Pioneer researchers included information and data from the Iowa Corn Yield Contest. M.S. thesis. Iowa State Uni- 1930 to 2011 (Smith et al., 2014). versity, Ames.

1990 www.crops.org crop science, vol. 57, july–august 2017 Oat 181). The first pages of each Leaflet“ F.C.” report of these Varietal testing in Iowa was very different for oats than trials provide a detailed description of the process. “These for corn–both in the testing process and the participating trials (were) conducted through a cooperation…between organizations. The Iowa Agricultural Experiment Sta- the Agronomy Section of the Agricultural Experiment tion, and L.C. Burnett in particular, played a key role in Station, the Agricultural Extension Service and the vari- the development and testing of oat varieties in the early ous Farm Bureaus in the counties where the trials (were) years. According to H.D. Hughes, the Experiment Station conducted.” The SCGT were conducted in nine counties was experimenting with oat in 1889 and reported that year that “corresponded roughly to the principle soil areas in the on the performance of 15 varieties (Hughes, 1946, p. 45). state.” They covered oat and wheat. There were usually 30 “The job of getting out new varieties, especially adapted to to 50 trials in most years (Hughes, 1945, p. 34). For the full the weather and soil conditions of Iowa and the Corn Belt reports of each trial, see Burnett and Dyas (1940–1943). generally, was not begun in an extensive way until 1907” Burnett extensively tested each variety for multiple years (Hughes, 1945, p. 27). Hughes’ report, which summarizes before sending it out to be used in the trials. “To begin with, oat production and variety development in Iowa pre-1945, each is planted in rows five feet long. Those that show enough includes considerable details for each oat variety in Iowa. He stuff are planted again the next year in rows a rod long. Then also highlights the work of L.C. Burnett who began Iowa if they continue to look good, they are moved up to 10-row oat variety testing in 1908 and published numerous bulle- plots, next to the special ‘elite’ nursery, and finally to the tins and articles on the topic. Burnett has been described as one-twentieth-acre plots, and the standard community grain “one of the most successful breeders of improved varieties trials out in the state” (Thompson, 1940, p. 14). of oat by the “pure-line” selection method in the United The Quaker Oats Company sponsored an Oats States” (Stanton, 1936, p. 357). Stanton also provided details Improvement Program (starting in 1964) in Iowa and then on the oat varieties Burnett helped to improve. later expanded it to include the top oat producing states: “In 1909, the work in Illinois having been discontinued, Minnesota, North Dakota, South Dakota, and Wisconsin. the Iowa station was made the headquarters for the testing of The goal was to teach high school students “the principles the oat selections (in the U.S.).” At that time, the most exten- of growing milling quality oat through participation in a sive tests were being conducted at the Iowa and Cornell Uni- yield contest” and the results “provided practical, on-farm versity experiment stations (Warburton et al. (1914), p. 2). “In evidence that oat yields in Iowa and the United States could 1912 (the Iowa Agricultural Experiment Station) reported on be substantially higher with careful management.” Students 48 varieties and in 1918 summarized 22 varieties that had selected a cultivar from a list of those acceptable for their been studied for 6 years and 17 varieties that had been studied state but “no other management variables were specified.” for 10 years” (Hughes, 1946, p. 45). Hughes does not refer- The student project yields were 47% higher than aver- ence any specific documents; however, the dates match those age Iowa farm yields (Marshall et al. (1992), p. 193–194). of various Iowa Agricultural Experiment Station bulletins. Unfortunately, yield data that Marshall provided was from For a detailed listing of these publications, see the Supple- unpublished reports supplied by a Quaker Oats Company mental Information file associated with this article. employee (A. Bruce Roskens) in 1990 and Marshall did Seven years after L.C. Burnett began the Iowa oat not include any variety-specific information. The program improvement program, the first hybrid variety went out ended in 2000 when PepsiCo bought Quaker Oats and the to farmers–the Iowa 103 in 1913 (Hughes, 1945, p. 43). original yield data has disappeared within company walls. When the first of the new oat varieties was available, farm- Published reports of oat variety tests in Iowa are ers throughout the state were invited to test this variety on available for 1889 to present with some gaps and overlap. their own farms in cooperation with the Station, by plant- This includes: ing a measured 0.41 ha (1 acre) in comparison with the • 1871, see Roberts (1872). variety they were growing. This method of distributing • 1889, 1891, 1898–1934, Bulletin (Iowa Agricultural and testing the new Station varieties was continued from Experiment Station), No. 6, 15, 96, 128, 175, 227, 344 1913 until 1938 (Hughes, 1945, p. 33–34). However, there • 1909–1912, see also USDA Department Bulletin, No. 99 were difficulties in threshing a small plot of grain and • 1910–1923, see also USDA Department Bulletin, No. 1343 keeping it free from mixture with other varieties. This led to changes in the testing process and the establishment of • 1916–1938, see Thurman (1940). the Standard Community Grain Trials. • 1938–1942, Farm Science Reporter, vol. 4, no. 1, January Standard Community Grain Trials (SCGT) were a series 1943, p. 6–7. of varietal experiments from 1938 to 1943 but very little • 1940–1943, see Burnett and Dyas, 1940–1943, Leaflet FC, information about them still exists. “Burnett initiated the No.11, 13, 15–16 Standard Community Grain Trials in 1938 to obtain more • 1941–1951, Annual Report of Cereal Breeding Projects data and to show newer varieties locally” (Troyer, 2004, p.

crop science, vol. 57, july–august 2017 www.crops.org 1991 • 1950–1963, Agronomy series No. 204, 225, 251, 284, 319, soybean work was taken over by Charles R. Weber and 385, 413, 449, 478, 507, 647 then Robert R. Kalton when Weber was also called into • 1960–1993, AG series as AG-10-* military duty. In 1937, “[t]he field soybean variety yield tests • 1995–2007, Pamphlet or Pm series as Pm-1645 conducted at Ames consisted of four sub-projects, namely, • 1977–2015, see also Annual Progress Report for Northeast Soybean Variety Test, Soybean Rod 2-Row Test, Rod Row Research and Demonstration Farm Test, and Soybean Hay Variety Test” (Burnett and Reddy, 1937). Descriptions and results of these are available on p. • 2009–2014, http://fpr.extension.iastate.edu/ListArticles. aspx?Field=Farm&Value=3 54 to 107 of the Soybean Investigations Annual Report for 1937. The types of tests conducted varied slightly each year. • 2010–2016, “Oat Variety Trials” in Farm Progress Reports Unlike other Iowa field crops, research on soybean For complete details on these publications, see the became organized and disseminated as part of regional Supplemental Information file for this article. efforts in 1936 with the organization of the Regional Soy- Oat variety testing is still taking place at the ISU bean Industrial Products Laboratory. This was a joint ven- Research and Demonstration Farms each year but the ture between the U.S. Department of Agriculture and the results are neither widely distributed nor as readily findable Agricultural Experiment Stations of the 12 states in the as those for corn and soybean. The URL changes slightly north-central region. Regional variety tests were orga- each year but 2009 to 2014 are available from the North- nized and implemented by this Laboratory (Weiss, 1949, east Research and Demonstration Farm reports website and p. 150). Soybean varietal test results for each state were from 2010 onward they are available on the Digital Reposi- included within one of two series-Results of the Cooperative tory at ISU at: http://lib.dr.iastate.edu/farms_reports/. Uniform Soybean Tests (1941–1965) and Uniform Soybean Tests (1966-present). Each series was divided into two separate Soybean publications, one for northern states and one for south- Soybean evaluations at the Iowa Agricultural Experiment ern states. The title of the North region varied over time Station can be traced as far back as 1898, but the first year including North Central States, North Central Region, that soybean hectares were mentioned in agricultural statis- and Northern Region. Results for northern states (which tics reports as being harvested for the bean (rather than hay) includes Iowa) for 2003 to present are online at: https:// was in 1923. It was not until the 1930s that the soybean crop ag.purdue.edu/btny/Extension/Pages/extpubs.aspx began to have a real impact on Iowa agriculture (Hughes, Soybean was often called soy beans or soya beans and 1941/1942, p. 19–25). Hughes provides an excellent his- spelled as two separate words rather than one. Since they tory of soybean experiments in Iowa from 1910 to 1940. were originally grown as a forage crop, and also sown in Although he does not provide information on yields for spe- with other crops (such as corn) as a companion crop, it can cific varieties, he does summarize which were recommended be challenging to locate yield results. Published reports of for specific time periods and lists individual researchers and soybean variety tests in Iowa are generally available for key Iowa State College publications during this time period. 1900 to present, although there are a few gaps and some A surprisingly large number of soybean varieties were overlap. This includes: being tested in Iowa in the early 1900s. “One hundred and • 1900–1901, Bulletin (Iowa Agricultural Experiment fifty-seven varieties of soybean have been under observa- Station), No. 45 and 55 tion at Ames” (Hughes and Wilkins, 1925). “Soybeans for • 1910–1929, New Crop Varieties on Iowa Farms (by Joe Iowa” is one of the best sources of information on early Robinson at 1929) soybean variety testing in Iowa. This Bulletin reported the • 1913–1921, see Knobbs (1922). results of variety tests covering 6- to 10-year averages and most of the cultural studies were 5 to 8 years in length. It • 1915–1924, Bulletin (Iowa Agricultural Experiment Station), No. 288 provides information on the varieties and yields from 1915 to 1924 and has very comprehensive, detailed informa- • 1916–1938, see Thurman (1940). tion on cultural methods. Although Wilkins was listed as • 1937, 1939–1941, 1944–1946, Soybean Investigations: the second author on many Iowa soybean publications, he Annual Report was the leader of the soybean project at Iowa State Col- • 1939–1946, Agronomy series no. 41 and 59 lege until his death in 1936 (Anonymous, 1944) and he • 1943–1948, RSLM No. 195 co-authored many other articles on soybean varieties and • 1958–1962, Agronomy series no. 591 production with H.D. Hughes. • 1960–1996, AG series, No. 18-* (the rest of the report In 1937, Martin G. Weiss took over the leadership of number changed each year to include the last digit of the soybean projects at Iowa State College and began something year the report was issued–e.g., AG-18–5 was used for officially called Soybean Variety Tests in Iowa. Weiss was called trials for 1965, 1975, 1985, 1995, etc.) to active military duty in January 1942 (World War II) and • 1997–2010, AG series, no. 18 (rev.)

1992 www.crops.org crop science, vol. 57, july–august 2017 • 2006–present, on the Iowa Crop Performance Testing better management by the producers” (Whigham, 2002). website (click on Soybeans/Reports to access the older ones) Soybean is still a major crop today and is one of the two remaining high-profile crop performance tests being con- For complete details on these publications, see the ducted every year by Agricultural Experiment Station Supplemental Information file for this article. staff at Iowa State University. Soybean variety yield information is also available from the Iowa Soybean Yield Contest results. This was a growers’ Other Iowa Crop Performance Tests contest (a.k.a. Five Acre Soybean Yield Contest) and was Alfalfa created at the request of the Iowa Soybean Processors in Alfalfa is one of the most common forage crops. Unlike corn 1941 (Robinson and Knott, 1963, p. 58). The Iowa Corn and soybean, “a planting of alfalfa is exposed to 3 or more years and Small Grain Growers’ Association conducted the soy- of summer and winter climatic stresses, at least 10 harvests, bean contests and modelled them after the Master Corn and numerous pest insects, diseases, and nematodes. The crop Grower’s Contests as locally sponsored events (e.g., by is harvested numerous times in one season, produces several local Farm Bureau offices) in which the winning entries regrowths, goes through a dormancy period, and fixes nitro- were submitted to the district-level contest and then to the gen each year. Several years of multiple annual harvests are state level. Iowa State University Library Archives records needed to collect yield and adaptation data” (Barnes, 1988, p. for these contests from 1938 to 1943 contain only lists of 18). Alfalfa is high in protein and has proven useful in a myriad entrants, winners, and county name. Variety yield informa- of ways including, restoring N to soil, breaking down fertil- tion was included for the Iowa Soybean Yield Contest from izers and other contaminants in soil and water, as a food source 1944 to 1967 (Iowa Crop Improvement Association, 1902– high in antioxidants, and the stems can be gasified and burned ongoing). For many years, the results of the Master Soybean to produce electricity (Russelle, 2001). It is one of many crops Growers’ Contest were also reprinted and made available as being tested for use in biomass production. part of the Iowa Corn and Small Grain Growers Associa- Alfalfa production in Iowa gradually increased from tion annual report in the Iowa Year Book of Agriculture. 1909 up through 1914 and then experienced a major surge Strayer Seed Farms (in Hudson, IA) saw the usefulness in 1915. From 1930 to 1939, alfalfa hay was being har- of growing soybean for human foods and, in 1936, were vested on 305,860 ha (746,000 acres) in Iowa and from the first to produce specialty soybean in Iowa. George M. 1940 to 1949 it was harvested on 368,590 ha (899,000 Strayer, through his company Agricultural Exports Inc., was acres) (Bolton, 1962, p. 38). Bolton’s Alfalfa book is one of instrumental in increasing the export market for soybean in the few publications to provide individual U.S. state statis- the mid-1950s. Strayer was the first to export a specific vari- tics for alfalfa production separate from other types of hay. ety of soybean (Jade) useful for food processing companies. Early publications related to Iowa field crops usually He succeeded in proving there was a market for them and lumped alfalfa in with other hay crops; however, in later soon other big U.S. grain companies began offering the high years, as alfalfa became known as the “Queen of Forages,” quality, high oil soybean to export markets (Bernard, 1978). it became easier to locate alfalfa-specific variety and yield For more details on the growth of U.S. soybean production information. Published reports of alfalfa variety experiments and soybean marketing efforts see Strayer (1962). The first- in Iowa are available for 1897 to 2007 with some gaps and ever report specific to specialty soybean was the 1993Iowa overlap. For a detailed listing of these publications, see the Specialty Soybean Test Report. At the time, 50% of all soybean Supplemental Information file associated with this article. grown in the state were specialty soybean (Heck, 1994). The 1994 and 1995 versions were called Iowa Gold Specialty Soy- Barley bean Test Report. All three of these publications were pub- “Barley varieties are classified as either six-row or two- lished within the AG series from the Iowa State University row depending on the physical arrangement of the kernels Extension and were issued as inserts in the February 1994, on the plant. Six-row barley is grown primarily in North 1995, and 1996 issues of Iowa Soybean Review. These publica- Dakota, Minnesota, South Dakota, and Idaho. Two-row tions were partially funded using Soybean Checkoff Program barley is grown in Montana, Idaho, Colorado, Wyoming, funding. Specialty soybean test results for 2000 to 2004 are Washington, Oregon, and California” (Taylor et al., 2016). available as part of Iowa State Research Farm Progress Reports. As demonstrated in this quote, Iowa is rarely mentioned as Iowa State University researchers also began a soybean a state that produces barley and yet records for agricultural cyst nematode resistant variety trial program in 1990. A statistics in the United States show barley was being grown 2005 summary of the program provides a nice history and on Iowa farms in 1866, albeit only 27,060 ha (66,000 acres) overview (Tylka, 2006). were harvested that year. Barley was at its peak in 1899 and “Yield averages per decade indicate that the [soybean] then steadily decreased until 1927–1938 when it resurged for yields increased from 14 bushels per acre in the 1920s to 43 a short time (Iowa Crop and Livestock Reporting Service, bushels per acre in the 1990s, a threefold increase. Yields 1938, p. 432). This pattern is typical of many barley-producing have made steady progress due to improved varieties and crop science, vol. 57, july–august 2017 www.crops.org 1993 areas in the early years. Barley was susceptible to disease that and Demonstration Farm Reports for 2004. Published came with corn production. As corn production increased in reports of flax experiments at the Iowa Agricultural Exper- an area, barley production shifted West and North to areas iment Station are available for 1921 to 1972. For a detailed where there was no corn. In the 1930s the grain industry listing of these publications, see the Supplemental Informa- began paying premiums “for high grades of certain [barley] tion file associated with this article. varieties which stimulated considerable interest in the crop.” This encouraged farmers to grow specific varieties more suit- Sorghum able for use in malting industries (Burnett and Reddy, 1937). Sorghum was popular among pioneer farmers and is Barley production in the United States is once again mainly grown in drought regions. Although it did not on the rise due to an increase in microbreweries or craft make the historical crops list in the 1938 Iowa Year Book of breweries starting in the 1980s and the promotion of Agriculture (Iowa Crop and Livestock Reporting Service, whole grain health benefits. This includes not only the 1938), sorghum was being grown in Iowa in the 1800s. In fiber content but also research investigations that tie it to 1869, there was a push from the Iowa State Agricultural lower cholesterol and blood glucose levels (Ullrich, 2011, Society for farmers to produce more sorghum syrup as p. 3). Currently, barley is used for livestock feed, human it provided a much higher value per .41 ha (1 acre) than food, and malt production. “Each of these uses is best other crops. Sorghum was estimated to generate $71.94 met with specific barley varieties. About three-quarters per .41 ha (1 acre) while wheat was only $20.07 and corn of barley production is used for food/malt purposes, and only $15.82 per 0.41 ha (1 acre) (Schaffer, 1870, p. 16–18). the remainder is used as animal feed” (Taylor et al., 2016). Relatively little has been published about sorghum Published reports of barley variety experiments in Iowa variety testing in Iowa. There was a very brief mention of are available for 1892 to 2007 with some gaps and over- Iowa Experiment Station work on sorghum varieties in a lap. Results of early field crop experiments in Iowa were 1936 article on “Sorghum Improvement”: published annually and the list of included crops changed each year. In 1892 it included corn, barley, and ensilage “Other selected strains of the Black Amber type (Kent, 1892). The next issue that included barley was in of sorgo have been developed, including the Ames 1900 (Atkinson, 1901). Information on other Iowa reports Amber by the Iowa Agricultural Experiment Sta- that include barley variety test results is available in the tion. Selected natural hybrids of the variety have Supplemental Information file associated with this article. resulted in the isolation of such varieties as Folger, Colman, and possibly Red Amber. Folger was Flax selected by a farmer of that name, living near Flax has had a rocky history as a field crop. In pioneer days, Shenandoah, Iowa, during the eighties. Waconia it was considered to be a crop that was only suitable for Orange, selected and distributed by the Waconia planting on “new ground.” Once a field had been planted Sorghum Mills, Cedar Rapids, Iowa, is a new, dis- to flax, the following year’s crops exhibited significantly tinct strain of Orange sorgo” (Martin, 1936, p. 547). poorer yields and were prone to disease. With the intro- The Iowa Sorghum Performance Test was created in 1958 duction of disease-resistant varieties, it became profitable and led by R.E. Atkins, J.G. Wheat, and C.D. Hutchcroft to grow on Iowa farms. “In states leading in flax produc- (Robinson and Knott, 1963, p. 115–117) to test combine tion from 1925 to 1934, flax has given higher acre returns type grain sorghum variety yields. Also referred to as than spring wheat, barley, or oats” (Reddy and Burnett, Sorghum Performance Trials, these tests were conducted as 1936, p. 4). Some of this value was due to it fitting into part of the Iowa Crop Improvement Association research in crop rotations the same as oat and other small grains (it cooperation with Iowa State University. “[T]o help defray was the ideal crop to follow corn) and it was harvested and the expenses of the test, an entry fee of $20 was charged for threshed with the same equipment. The only difference each entry tested in each field. The entrant had the option was the cost of the seed. In Iowa, flax was primarily grown of entering any hybrid in one or more fields.” Robinson in northwestern counties (Burnett and Johnson, 1944). and Knott provide details of planting arrangements According to data from the National Agricultural Sta- and harvesting for the first years of these tests. The tests tistics Service, production of flax in Iowa started dwindling continued in Iowa up through 1989 and results were in the 1950s and has not been grown commercially in Iowa published with the AG series as AG-16 each year. since 1971. Iowa State University researchers began flax Starting in 2008, Dr. Salas Fernandez initiated a experiments again in 2004. For example, variety test results sorghum breeding program for biofuel production at from experiments in 2005 are mentioned in an Iowa State Iowa State University (using sweet sorghum). The main University (ISU) thesis from 2010 (Gailans, 2010, p. 1), in goal of the program is to conduct research that leads to several ISU Extension publications within the PM series– and supports the development of sorghum germplasm for No. 2020 and 2058, and in the ISU Northwest Research biofuel production adapted to Iowa (Fernandez, n.d.).

1994 www.crops.org crop science, vol. 57, july–august 2017 Outside of Iowa, there is a National Sorghum Producers members of these associations. Some research records reside Yield Contest sponsored by the National Sorghum with the organizations and others have been transferred to Producers. This contest provides farmers the opportunity university archives. The largest group was the Iowa Crop to compete with farmers across the U.S. Sorghum Belt. Improvement Association. Raw data and records from this One of their webpages has a list of the U.S. sorghum hybrid group are on file in the Iowa State University Library, Spe- trial results that are available online for each U.S. state. cial Collections and University Archives Department. Harder to find, but just as interesting, are crop variety Wheat (Spring and Winter) and Triticale yield tests conducted by individual farmers. In Iowa, one Like sorghum, wheat is another crop that was primarily of the more famous was the Dennis Gustafson Plot Tests, grown in Iowa during the mid-to-late 1800s. Unlike sor- in Crawford County. Gustafson began conducting variety ghum, record high wheat prices in the mid-2000s resulted tests in 1963 for his own information but his fame grew in a resurgence of interest in spring wheat production in as he increased the number of varieties being tested and Iowa (Gibson, 2008). seed companies began including this information in their During the Civil War, Iowa ranked second nation- advertisements. For example, a 12 Jan. 1969 ad in the Des ally in wheat production (Schwieder, 1996, p. 134). It Moines Register for Crow’s Hybrid Corn “won Dennis Gus- remained a profitable crop in Iowa until 1870 (Speer, tafson plot tests!” In 1967, he tested 55 varieties and in 1968 1889, p. 199). Even though Iowa agronomists encouraged increased it to 165 varieties, with a lot of help from volunteers farmers to move away from wheat in favor of corn, farm- in the area. He was inundated with requests for a booklet ers continued to grow wheat. “In 1875 Iowa wheat pro- outlining results of his tests each year (Anonymous, 1968). duction reached its peak. It took a disaster in the form Experiment Station staff were also happy to educate farmers of grasshopper plagues to finally drive farmers away from wanting to test varieties on their own farms. They provided producing wheat. They switched to corn, which they fed fairly detailed instructions on how to lay out the plots, keep to livestock” (Schwieder, n.d.). records, harvest, and interpret the results (Wallize, 1968). Wheat variety tests are somewhat different from other Iowa crops in that some reports covered all types of wheat, YIELD TESTING PUBLICATIONS others were specific to winter wheat or spring wheat, and IN OTHER U.S. STATES additional reports covered wheat and triticale. As a cross Agricultural Experiment Stations in a large number of U.S. between wheat and rye, triticale (× Triticosecale) has shown states have been testing crop varieties for many years. A promise as: a forage crop; a replacement for corn in animal Ph.D. dissertation by Ludwig Auer (Auer, 1963) provides feed; a viable option in biofuel production; and, if different an appendix listing field crop variety yield reports from varieties are developed more fully, as a food grain (Hansen many U.S. states up through 1963. Although he includes and Tyler, 2012). Research on triticale varieties in Iowa is an impressive list of references for each crop, it should only likely to expand even more in the near future. Published be considered a starting point for locating test results. reports of wheat and triticale variety experiments in Iowa Founders of state agricultural experiment stations recog- are available for 1889 to 2008 with some gaps and overlap. nized the need for publications from the very beginning and For a detailed listing of these publications, see the Supple- established recommendations for core publications (Knob- mental Information file associated with this article. lauch et al. (1962), p. 143–157) but the actual practices varied somewhat at each station. Over time, publications became Other Field Crop Testing in Iowa divided into two main types–those aimed at the general Many other less formal crop experiments have taken public and those with detailed research results. Publications place at the Iowa Agricultural Experiment Station over aimed at the general public were often issued by state coop- the years. This includes crops such as sugar beet, cowpea, erative extension offices while the more technical research potato, clover, and many forage grasses. Results from publications were issued by Experiment Stations. Beyond these were often summarized and included in articles this, it was also standard practice to produce in-house (often aimed at farmers in magazines such as Iowa Farm Science mimeographed) research reports for station staff, some of or educational leaflets in the Circular series issued by Iowa which were also shared externally on request by interested State University Extension. For a listing of these, see the farmers, USDA scientists, and researchers in private indus- Supplemental Information file for this article. try. Variety yield test results were often partially reprinted or Tests for specific crops were often co-sponsored or co- summarized in journal articles authored by primary inves- conducted with professional crop associations (e.g., the Iowa tigators, specialized professional association newsletters, or Crop Improvement Association, the American Soybean used as the basis for graduate student theses. The small two to Association, the National Oat Conference, etc.), USDA four page mimeographed reports were not widely distributed research centers (such as the U.S. Regional Soybean Labora- and were usually only kept in researcher office files. Some of tory) and agricultural companies or specific grain industries. these have been donated to university library archives over Researchers from the Experiment Station were often active crop science, vol. 57, july–august 2017 www.crops.org 1995 Table 1. Summary of known Iowa field crop variety yield test- Station tests were considered to be more impartial due to their ing results. Gap years may (or may not) have actually been published. In some years, weather conditions destroyed anonymized testing processes. Each year, variety test results experiments or made yield test results impossible to compare. were used to help farmers make informed decisions about profitable varieties and improve production processes. Results Crop Years covered in known publications also informed crop breeding efforts to increase yields per acre Alfalfa 1882–1883, 1885–1886, 1896, 1910–2007 and stave off food shortages due to weather catastrophes and an Barley 1871, 1892, 1900, 1911–1943, 1946–2008 Corn 1892, 1895–1896, 1904–present ever-increasing world population. The most successful varieties Flax 1921–1972 were those which were higher profit for farmers and also had Forages 1880–1950, 1952–1957, 1961–1974, 2010–2013 a plethora of industrial uses. In Iowa, corn variety test records Oat 1871, 1889, 1891, 1898–present are easier to locate than those of other crops and, surprisingly, Potato 1882–1883, 1886, 1871, 1889–1891, 1896, 1910–1912, these tests were taking place well before the founding of the 1915, 1964 Iowa Corn Yield Test in 1920; however, a lot of confusion Rye 1871, 1882–1883 exists between results from corn shows, corn contests and corn Sorghum 1913–1938, 1958–1989 variety tests as well as growers’ tests and those of the Iowa State Soybean 1900–1901, 1910–1948, 1958–present Agricultural Experiment Station. Each field crop developed its Sugar beet 1888–1894, 1897, 2008–2009 own unique pattern of research and publication practice and Triticale 2002–2008 Wheat 1871, 1889–1942, 1947–2008 results for some crop variety tests were distributed wider than those of other crops. the years. Results for some U.S. states may be stored in a There are many untapped sources for varietal data, men- private company archive or in association files rather than in tioned above and included in the Supplemental Information a publicly accessible research library. file for this article. The majority of which are not avail- Agricultural experiment station publications have been able online. Agronomists should be encouraged to check digitized in some U.S. states (most notably those from Texas with their nearest land grant university library archives for A&M, Colorado State University, Kansas State University, historic agricultural experiment station publications, crop Cornell University, and the State University Libraries of association records, master’s theses, field notebooks, and/ Florida); however, there are many, many more that have not or manuscript records of individual local crop researcher yet been digitized. This is due to a lack of available funding, records. Investigating crop experiment history in a specific incomplete collections, and (to be honest) a lack of knowledge U.S. state and identifying the leading researchers for that about their existence in libraries or archives due to staffing crop can aid in locating data on crop experiment results, turnovers and the ephemeral nature of some publication series. whether from performance trial results or other written HathiTrust Digital Library (https://www.hathitrust. accounts authored by the primary researchers. org/) contains some U.S. agricultural experiment station Variety tests from the past have the potential to inform new publications but can be extremely confusing to search research efforts today. A recent Nature Plants editorial asserts through given the somewhat generic nature of publica- that heritage varieties are vital to future crop breeding efforts tion titles such as Bulletin or Circular and numerous publi- and to counter problems of future food security (Anonymous, cation title changes over the years. Only those published 2016). This concern is echoed by others such as Noldin et al., prior to 1923 are likely to be available in full-text through who maintain that “commercial varieties have reduced genetic HathiTrust due to copyright restrictions. variability compared with the diversity of the cultivated species The National Agriculture Library in Beltsville, MD, because elite materials are used recurrently in breeding pro- also maintains a large collection of state agricultural grams. Such a situation constitutes a bottleneck that challenges experiment station publications. Although many are not future response to selection” (Noldin et al. (2017), p. 660). As individually cataloged, and only sporadically included in agronomists look to find new sources for biofuels and other AGRICOLA, they can be perused on site. industrial uses for various crops, data from previously grown varieties could be useful. The results of earlier tests can be used SUMMARY AND CONCLUSIONS in longitudinal studies or serve as the basis for additional types Iowa researchers have been conducting crop variety tests with of previously untested characteristics. For example, Specht and a wide range of crops in formal and informal testing envi- Williams (1978) examined soybean cultivars released to pro- ronments for almost 150 years (Table 1). What started as a ducers from 1902 to 1977 to screen them for heat tolerance and hodgepodge of grower contests, student projects, and individ- correlate that to yields. Since heat tolerance was not one of the ual farmer testing efforts gradually became a unified, statewide factors included in early trials, they obtained historic cultivars program of variety testing by the Iowa Crop Improvement from the Regional Soybean Research Laboratory in Illinois, Association and the Iowa Agricultural Experiment Station planted the varieties and measured the results from 1977 to under uniform growing conditions. Private seed companies 1979. Re-testing heritage varieties utilizing modern produc- also conducted their own variety tests but the Experiment tion methods could also improve yield results or prove viable

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