Peer-Reviewed Journal Articles

*BS, MS or Ph.D. student supervised by Heaton
† Corresponding author

Chang H., Snow A., Mariti M., Evans M., Heaton E.A. (2018) Extent of pollen-mediated gene flow and seed longevity in swtichgrass (Panicum virgatum L.): Implications for biosafety procedures. Biomass Bioenergy. 109: 114-124. doi: 10.1016/j.biombioe.2017.12.016. Abstract.

This paper highlights important knoledge gaps in our understanding of switchgrass pollen movement and associated gene flow. While gene flow is not as likely in switchgrass as in some specias, it poses real risk with wide-spread production of improved switchgrass.
Lee D.K., Aberle E., Anderson E.K., Anderson W., Baldwin B.S., Baltensperger D., Barrett M., Blumenthal J., Bonos S., Bouton J., Bransby D.I., Brummer C., Burks P.S., Chen C., Daly C., Egenolf J., Farris R.L., Fike J.H., Gaussoin R., Gill J.R., Gravois K., Halbleib M.D., Hale A., Hanna W., Harmoney K., Heaton E.A., Heiniger R.W., Hoffman L., Hong C.O., Kakani G., Kallenbach R., Macoon B., Medley J.C., Missaoui A., Mitchell R., Moore K.J., Morrison J.I., Odvody G.N., Richwine J.D., Osgoshi R., Parrish J.R., Quinn L., Richard E., Rooney W.L., Rushing J.B., Schnell R., Sousek M., Staggenborg S.A., Tew T., Uehara G., Viands D.R., Voight T., Williams D., Williams L., Wilson L.T., Wycislo A., Yang L. & Owens V. (2018) Biomass production of herbaceous energy crops in the United States: field trial results and yield potential maps from the multiyear regional feedstock partnership. GCBB 10: 698-716. doi: 10.1111/gcbb.12493. Abstract.

The Regional Feedstock Partnership was the first and largest network of energy crop research trials in the US to date. This paper provides seminal summary information from rigorous field trials that have since been used to guide research, funding, and policy by providing the foundation for the Dept. of Energy Billion Ton Assessment.
Brandes E.*, McNunn G.S., Schulte L.A., Muth D.J., VAnloocke A. & Heaton E.A. (2018) Targeted subfield switchgrass integration could improve the farm economy, water quality, and bioenergy feedstock production. GCBB 10: 199-212. doi: 10.1111/gcbb.12481. Abstract.

This novel analysis coupled publically-available, spatially-explicit land use and profitability information (developed in Brandes et al. 2016) with mechanistic biogeochemical model (DNDC) to show that planting switchgrass only on parts of cropland that were unprofitable 2012-2015 could reduce N loss from those field by 38%, getting Iowa near its Nutrient Reduction Strategy goals while simultaneously improving the farm economy.
Tejera M.* & Heaton E.A.(2017) Description and codification of Miscanthus x giganteus morphological development for phenological assessment. Front. Plant Sci 8: 1726.doi: 10.3389/fpls.2017.01726. Abstract.

This paper describes the first phenological scale for M.x giganteus, providing a tool that practitioners and academics alike can use to describe and manage M.x giganteus according to growth stage rather than arbitrary calendar or weather dates, as had been done previously.
Miriti M., Ibrahim T., Palik D., Bonin C.L., Heaton E.A., Mutegi E. & Snow A. (2017) Growth and fucundity of fertile Miscanthus x giganteus ('PowerCane') compared to feral and ornamental Miscanthus sinensis in a common garden experiment: implications for invasion. Ecology and Evolution. 7:5703-5712. Abstract.

This was the first to compare improved fertile miscanthus with both feral and ornamental lines in multiple locations. The improved variety 'Power Cane' has growth and survival characteristics that make it reasonably likely to be invasive if widely cultivated under current management practices.
Fike J., Pease J., Owens V., Farris R., Hansen J., Heaton E.A., Hong C., Mayton H., Mitchell R., & Viands, D. (2017) Switchgrass nitrogen response and cost of production on diverse sites. GCBB. doi: 10.1111/gcbb.12444. Abstract.
Burke R.H.*, Moore K.J., Shipitalo M.J., Miguez F.E. & Heaton E.A.† (2017). All washed out? Foliar nutrient resorption and leaching in senescing swtichgrass. BioEnergy Res. 10 (2): 305-316. Abstract.

This study evaluated switchgrass foliar nutrient leaching during the growing season.
Roby M., Salas-Fernandaez M., Heaton E.A., Miguez F.E. & VanLoocke A. (accepted) Biomass sorghum and maize have similiar water-use-efficiency under non-drought conditions in the rain-fed MidWest US. Agriculture and Forest Meteorology.
Yost M., Randall B.K., Kitchen N.R., Heaton E.A., & Myers R.L.(2016) Yield potential and nitrogen requirements of Miscanthus x giganteus on eroded soil. Agronomy J. 109: 684-695. Abstract.
Bonin C.L.*, Mutegi E., Snow A., Miriti M., Chang H. & Heaton E.A. (2016) Improved feedstock option or invasive risk? Comparing establishment and yields of fertile Miscanthus x giganteus with Miscanthus sinensis biotypes. Bioenergy Res.doi:10.1007/s12155-016-9808-1.Abstract.

This is the first study comparing fertile bioenergy, ornamental, and feral genotypes of M. x giganteus, finding that fertile bioenergy genotypes have greater potential to be invasive than ornamental or feral genotypes in the Midwest. Findings are best used to shape best practice recommendations.
Huang S., Hu G., Chennault C., Su L., Brandes E., Heaton E.A., Schulte L.A., Wang L. & Tyndall J.(2016) An agent-based simulation model of farmer decision making on bioenergy crop adoption. Energy 115:1188-1201.Abstract.

This paper uses a novel modeling technique to assess socioeconomic drivers and impacts of bioenergy in Iowa from a farmer's perspective.
Mutegi E., Bonin C.L., Heaton E.A., Chang C., Gernes C., Palik D., Miriti M. & Snow A. (2016) Population genetics and seed set in feral, ornamental Miscanthus sacchariflorus. Invasive Plant Science and Management. 9: 214-228. Abstract.

This paper is the first to examine the genetics and fecundity of feral M. sacchariflorus, a parent species of M. × giganteus that is found throughout the upper Midwest and could become invasive. We found that seed set is currently pollen-limited, but could change as populations expand.
Palik D., Snow A., Stottlemeyer A.L., Miriti M. & Heaton E.A. (2016) Relative performance of non-local cultivars and local, wild populations of switchgrass (Panicum virgatum) in competition experiements. PLOS1. doi:10.5061/dryad. 7b191. Abstract.

This paper is one of the few investigating the comparative invasive potential of improved and wild switchgrass, finding that there is some cause for concern that agronomically improved switchgrass is also more invasive than wildtype.
Brandes E., McNunn G.S., Schulte L.A., Bonner I.J., Muth D.J., Babcock B.A., Sharma B., & Heaton E.A. (2016) Subfield profitability analysis reveals an economic case for cropland diversification. Environmental Research Letters.doi:10.1088/1748-9326/11/1/014009. Abstract.

This paper is the first showing differential senescence in perennial grasses with plant age, i.e., plants ‘learn’ how to senesce with age, with basic and applied science implications.
Zaib M.A., Moore K.J., Archontoulis S.V., Heaton E.A., Lenssen A.W. & Fei S. (2016) Compositional differences among upland and lowland switchgrass ecoptypes grown as bioenergy feedstock. Biomass & Bioenergy. 87: 169-177.Abstract.

This paper is a solid contribution to understanding of compositional differences between upland and lowland switchgrass ecotypes.
Randall B.K.,Yost M., Kitchen N.R., Heaton E.A., Stelzer H.E. & Thompson A.L. (2016) Impact of rhizome quality on Miscanthus establishment in claypan soil landscape. Industrial Crops & Products. 85:331-340.Abstract.

This paper demonstrated that Miscanthus can effectively establish under soil conditions that severely limit maize production, even within a range of rhizome quality.
Wilson D.M.*, Gunther T.P., Schulte L.A., Moore K.J., & Heaton E.A.† (2016) Variety interacts with space and time to influence switchgrass quality. Crop Sci.. 56: 773-785. Abstract.

This is one of the few papers to tie landscape position to biofuel quality, and the first to show that plant mineral composition is most affected by spatial factors, while plant structural composition is most affected by temporal factors, thus enabling precision management for improved biofuel quality and ecosystem function.
Sharma B., Brandes E.*, Khanchi A., Heaton E.A., & Miguez F.E. (2015) Evaluation of microalgae biofuel production potential and cultivation sites using geographic information systems: A review. Bioenergy Res.. 8:1714-1734. Abstract.

This paper is the first showing differential senescence in perennial grasses with plant age, i.e., plants ‘learn’ how to senesce with age, with basic and applied science implications.
Boersma N.N.*, Dohleman F.G., Miguez F.E., & Heaton E.A.† (2015) Autumnal leaf senescence in Miscanthus × giganteus and leaf [N] differ by stand age. J Experimental Botany. DOI: 10.1093/jxb/erv129. Abstract.

This study evaluated poor first winter survial in Miscanthus × giganteus through an assesment of paired fist-year stands with older stands in a side-by-side trial to separate the effect of weather from stand age.
Bonin, C.L.*, Heaton E.A., Cogdill T.J., & Moore K.J. (2015) Management of sweet sorghum for biomass production. Sugar Tech. DOI: 10.1007/s12355-015-0377-y. Abstract.

This study explored sweet sorghum planting and seeding rates, row-widths, and fertilizer rates to maximize yields, carbohydrates, and theoretical ethanol yields in central Iowa.
Salas Fernandez M.G., Strand K., Hamblin M., Westgate M., Heaton E.A. & Kresovich S. (2014) Genetic analysis and phenotypic characterization of leaf photosynthesis capacity in sorghum (Sorghum spp.) diversity panel. Genetic Resourses and Crop Evolution. 62:939-950.Abstract.

One of the first efforts to use photosynthetic capacity as a trait to breed for stress tolerance in sorghum.
Hong C.O., Owens V.N., Bransby D., Farris R., Fike J., Heaton E.A., Kim S., Mayton H., Mitchell R., & Viands D. (2014) Switchgrass response to nitrogen fertilizer across diverse environments in the USA: a regional feedstock partnership report. Bioenergy Research. 7:777-788. Abstract.

This is the second paper from the US Sun Grant Initiative Regional Feedstock Partnership project on switchgrass, a transcontinental experiment informing switchgrass growth and production at a commercially relevant scale across diverse environments (Sun Grant Partnership).
Boersma N.N.* & Heaton E.A. †. (2014) Propagation method affect Miscanthus x giganteus developmental morphology. Part 1 of a 2 part series on the effects of Miscanthus x giganteus propagation method on growth and productivity. Industrial Crops and Products. 57: 59-68. Abstract.

This study reports morphological similarities and differences between stem propagated plants and rhizome propagated plants.
Boersma N.N.* & Heaton E.A. †. (2014) Does propagation method affect yield and survival? The potential of Miscanthus x giganteus in Iowa, USA. Part 2 of a 2 part series on the effects of Miscanthus x giganteus propagation method on growth and productivity. Industrial Crops and Products. 57: 43-51. Abstract.

This study is the first to report Miscanthus x giganteus yields in Iowa
Wilson D.M.*, Heaton E.A. †, Schulte L.A., Gunther T.P., Shea M.E., Hall R.B., Headlee W.L., Moore K.J., & Boersma N.N. (2014) Establishment and short-term productivity of annual and perennial bioenergy crops across a landscape gradient. BioEnergy Research. 7:885-898. Abstract.

This study is the first of short-term biomass yields and perennnial establishment across a landscape gradient from the Landscape Biomass Project. Findings help explain why landscape is often disregarded in Midwestern crop management.
Bonin. C.L.*, Heaton E.A. †, & Barb, J.(2014) Miscanthus sacchariflorus- biofuel parent or new weed? Global Change Biology Bioenergy. 6:629-636. Abstract.

This review outlines the origin, uses, distribution, and invasive potential of M.sacchariflorus.
Owens V.N., Viands D.R., Mayton H.S., Fike J.H., Farris R., Heaton E.A., Bransby D.I.& Hong C.O. (2013) Nitrogen use in switchgrass grown for bioenergy across the USA Biomass and Bioenergy. 58: 286-293. Abstract.

This is the first paper from the US Sun Grant Initiative Regional Feedstock Partnership project on switchgrass, a transcontinental experiment informing switchgrass growth and production at a commercially relevant scale across diverse environments (Sun Grant Partnership).
Heaton E.A. †, Schulte L.A., Berti M., Langeveld H., Zegada-Lizarazu W., Parrish D., & Monti A. (2013) Managing a second-generation crop portfolio through sustainable intensification: Examples from the USA and EU. Biofpr. 7: 702-714. Abstract.

This review described three primary strategies of agricultural intensification - conventional, spatial, and temporal.
Coulman B., Dalai A., Heaton E.A., Lefsrud M., Levin D., Lemaux P.G., Neale D., Shoemaker S.P., Singh J., Smith D.L. & Whalen J.K. (2013) Developments in crops and management systems to improve lignocellulosic feedstock production BioFPR. 7:582-601. Abstract.

This paper provides a holistic view of woody and herbaceous feedstocks in North America.
Cole D.P., Smith E.A., Dalluge D., Wilson D.M. *, Heaton E.A., Brown R.C., & Young J.L. (2013) Molecular characterization of nitrogen-containing species in switchgrass bio-oils at various harvest times. Fuel. 111: 718-726 Abstract.

This study demonstrated nitrogen species, especially N2 compounds, dominate the bio-oil spectra in early summer, but decrease significantly in later harvest times.
Waramit N., Moore K.J., & Heaton E.A. (2014) Nitrogen and harvest date affect developmental morphology and biomass yield of warm-season grasses. Global Change Biology Bioenergy. 6: 534-543. Abstract.

This study demonstrated that warm-season grasses develop differently depending on management, with implications for modelled projections of biomass production and resource use.
Wilson D.M.*, Heaton E.A. †, Liebman M. & Moore K.J. (2013) Intra-seasonal changes in switchgrass nitrogen distribution compared to corn. Agronomy Journal. 105: 285-294. Abstract

Considerable evidence suggests switchgrass cycles N from above-ground tissues, but there are few papers tracking the movement of N to below-ground tissues. This paper provides a comprehensive inventory of both above- and below-ground inventories of N in switchgrass, allowing farmers to better assess plant nutrient demands and management strategies.
Arundale R., Dohleman F., Heaton E.A., McGrath J. Voigt, T. & Long S.P. (2014) Yields of Miscanthus x giganteus and Panicum virgatum decline with stand age in the Midwestern USA. Global Change Biology Bioenergy. 6: 1-13. Abstract.

This is the first report of longer-term yields of Miscanthus in the US. It shows a decline after 8 years that may prove significant for models of biomass availability in the nation.
Wilson D.M.*, Dalluge D.L., Rover M., Heaton E.A. †, Brown R.C. (2013) Crop management impacts biofuel quality: influence of switchgrass harvest time on yield, nitrogen, and ash of fast pyrolysis products. Bioenergy Research. 6: 103-113. Abstract.

Nitrogen (N) is contaminant in the process of upgrading bio-oil to useful fuel. This paper was the first to determine a predictive relationship between feedstock nitrogen concentration and that of resultant pyrolysis products. Not only did we find a robust relationship, thus providing the industry with a rapid and cost-effective means of assessing feedstock quality for pyrolysis, but we also found that bio-oil quality can improved simply by managing the harvest time of switchgrass feedstock.
Mannat R.K., Hallam A., Schulte L.A., Heaton E.A., Gunther T., Hall R.B., & Moore K.J. (2013) Farm-scale costs and returns for second generation bioenergy cropping systems in the US Corn Belt. Environmental Research Letters. 8: 1-13. Abstract.

This study evaluated the profitability of 2G cropping systems compared to the grain-based biofuel crops.
Boersma N.N.* & Heaton E.A. † (2012) Effects of temperature, illumination and node position on stem propagation of Miscanthus × giganteus. Global Change Biology Bioenergy. 4: 680-687. Abstract.

A major limitation to farmer adoption of Miscanthus is the cost of planting material. Here we identified optimum conditions for a novel propagation system using M. × giganteus stem cuttings that was as effective as traditional rhizome propagation, but that has potential to be at least 15 fold faster and cheaper.
Dohleman F.G., Heaton E.A., Arundale R.A. & Long, S.P. (2012) Seasonal dynamics of above- and below-ground biomass and nitrogen partitioning in Miscanthus x giganteus and Panicum virgatum across three growing seasons. Global Change Biology Bioenergy. 4: 534-544. Abstract.

This paper demonstrates seasonal cycling of N and biomass between above- and below-ground structures of Miscanthus and switchgrass over multiple years and locations. The robust data set is useful to modelers and other researchers in estimating the C and N budgets that can be expected from these crops in the central US.
Rogovska N., Laird D., Cruse R.M., Trabue S. & Heaton E.A. (2012) Germination tests for assessing biochar quality. Journal of Environmental Quality. 41: 1014-1022. Abstract.

Biochar has received considerable attention as a panacea for soil improvement and crop health, but conflicting data indicated can either help or harm plant growth. This paper provides methods for determining if a given biochar is likely to be useful as a soil amendment, thus shaping the future of biochar research.
Prasifka J., Buhay J.E., Sappinton T.W., Heaton E.A., Bradshaw J.D., & Gray, M.E. (2011) Stem-boring caterpillars of switchgrass in the Midwestern United States. Annals of the Entomological Society of America. 104: 507-514. Abstract

Switchgrass could be planted on millions of acres in the US as energy crop productions increases, but very little is known about its pests. This paper is the first to identify new stem boring caterpillars found in field trials across the Midwest.
Heaton E.A. †, Dohleman F.G., Miguez F., Juvik J.A., Lozovaya V., Widholm J. , Zabotina O.A., McIsaac G.F., David M.B., Voigt T.B., Boersma N.N., & Long S.P. (2010) Miscanthus: a promising biomass crop. In: Advances in Botanical Research (ed. Jean-Claude K. & Michel D.). vol. 56: 75-137. Academic Press.

Miscanthus is currently the subject of much active research, but synthesis of new information is lacking. This review is the most recent and comprehensive review of Miscanthus in the peer-reviewed literature today.
Goff B.M., Moore K.J., Fales S.L., & Heaton E.A. (2010) Double-cropping sorghum for biomass. Agronomy Journal. 102: 1586-1592. Abstract.

Sorghum is a traditional arable crop with great potential as a bioenergy feedstock, but very little data exists on its productivity in this capacity. This paper is one of few presenting biomass and energy production potential from sorghum grown in the Midwestern US.
Heaton E.A. †, Dohleman F.G. & Long S.P. (2009) Seasonal nitrogen dynamics of Miscanthus x giganteus and Panicum virgatum. Global Change Biology Bioenergy, 1, 297-307. Abstract.

This paper was the first to present nitrogen cycling information for Miscanthus × giganteus in the US, indicating the crop can produce high biomass yields with little external nitrogen application if managed properly, thus reducing excess nitrogen in the agro-ecosystem and improving crop sustainability. The article is the 3rd most highly cited in the journal, which has an Impact Factor of 2.4.
Dohleman F.G., Heaton E.A., Leakey A.D.B. & Long S.P. (2009) Does greater leaf-level photosynthesis contribute to greater solar energy conversion efficiency in Miscanthus when compared to switchgrass? Plant Cell and Environment, 32, 1525-1537. Abstract.

Understanding what limits biomass production of terrestrial plants will be important to meeting human energy demands in a bioenergy economy. In this paper we show mechanisms that enable Miscanthus to produce more than the "model" bioenergy crop, switchgrass.
Heaton E.A. †, Flavell R.B., Mascia P.N., Thomas S.R., Dohleman F.G. & Long S.P. (2008a) Herbaceous energy crop development: recent progress and future prospects. Current Opinion in Biotechnology, 19, 202-209. Abstract.

Energy crop development is a nascent and rapidly changing area of science. This article framed key, recent advances in research and policy related to energy crops in a context targeted to those in biotechnology.
Heaton E.A., Dohleman F.G. & Long S.P†. (2008b) Meeting US biofuel goals with less land: the potential of Miscanthus. Global Change Biology, 14, 2000-2014. Abstract.

This article was the first to present biomass yields of Miscanthus × giganteus in the US, showing it could produce enough renewable feedstock to meet US biofuel mandates on only the land currently used for corn ethanol production., thus helping launch US interest in Miscanthus. The article is in the top 3% of those cited from the journal, which has an Impact Factor of 6.3 and is ranked by ISI ScienceWatch as the most cited journal in Climate Change Research behind Science and Nature.
Rogers A., Allen D.J., Davey P.A., Morgan P.B., Ainsworth E.A., Bernacchi C.J., Cornic G., Dermody O., Dohleman F.G., Heaton E.A., Mahoney J., Zhu X.G., Delucia E.H., Ort D.R. & Long S.P. (2004) Leaf photosynthesis and carbohydrate dynamics of soybeans grown throughout their life-cycle under Free-Air Carbon dioxide Enrichment. Plant Cell and Environment, 27, 449-458. Abstract.

Carbohydrate dynamics determine the magnitude of photosynthetic response to elevated CO2 concentrations in soybean. This paper demonstrated that the photosynthetic increase of plants grown in the field is significantly less than previously demonstrated by growth chamber studies and contributed to revision of global estimates of plant productivity under projected climate change.
Heaton E.A., Clifton-Brown J., Voigt T.B., Jones M.B. & Long S.P. † (2004a) Miscanthus for Renewable Energy Generation: European Union Experience and Projections for Illinois.Mitigation and Adaption Strategies for Global Change. 9, 433-451. Abstract.

Miscanthus had never been grown in the US for biomass, despite a long history in the EU. Here we presented the case for Miscanthus, along with modeled predictions of biomass yield, which indicated Miscanthus could produce twice as much biomass as switchgrass, the leading biomass crop in the US at the time.
Heaton E.A., Voigt T. & Long S.P. † (2004b) A quantitative review comparing the yields of two candidate C-4 perennial biomass crops in relation to nitrogen, temperature and water. Biomass & Bioenergy, 27, 21-30. Abstract.

Miscanthus and switchgrass are leading energy crops in the EU and US respectively, but had not been compared on the same continent. This quantitative review compared published yields and concluded Miscanthus should produce about twice as much biomass than switchgrass per unit of water, heat or nitrogen fertilizer.
Ainsworth E.A., Davey P.A., Bernacchi C.J., Dermody O.C., Heaton E.A., Moore D.J., Morgan P.B., Naidu S.L., Ra H.S.Y., Zhu X.G., Curtis P.S. & Long S.P. (2002) A meta-analysis of elevated [CO2] effects on soybean (Glycine max) physiology, growth and yield. Global Change Biology, 8, 695-709. Abstract.

A plethora of studies had investigated the effects of elevated CO2 concentrations on soybeans, with no clear consensus of results. This meta-analysis revealed statistically significant treatment effects as well as artifacts of measurement conditions, thus leading to changes in accepted research methodology.