Schwinning Lab

Plant Ecology

Yang Tse


Corn and Bean

The mixture of corn and bean is a classic intercrop combination

Intercropping is an ancient farming practice in which crops are going together in a field rather than separately in monocultures. Increased trait diversity and facilitative interactions between species combine to produce higher and/or more stable crop yields over time. Modern agriculture, as practiced in the industrialized nations using industrial fertilizer, insecticides and herbicides, made intercropping all but obsolete. However, the resurgence of low input and organic agriculture has recently rekindled the interest in intercropping in Europe and the USA. Combinations of nitrogen fixing legumes (e.g. beans) and C4 cereals (e.g., corn, millet, sorghum), sometimes in combination with squash ("The Three Sisters") are particularly common.

The productivity of intercropping systems depends not only on the species selection, but also on the densities, planting arrangements and the timing of planting. Graduate student Sarah Eisenmenger is currently investigating the consequences of varying the timing of bean relative to corn establishment. She is testing the hypothesis that small variation in planting order affects intercrop performance and that there may be an optimal planting order for bean and corn intercrops. This project is hosted by "My Father's Farm", an cerified organic farm in Seguin, Texas.




Lab News

Recent student presentations

Nathan Custer presented on his research at the Ecological Society of America Meeting in Portland. The title of his presentation was "Effect of transplant size on early survivorship". The paper was presented in a session on "Multiple Common Garden Experiments for Meeting Restoration Challenges: Difficulties and Potential Pitfalls" organized by Susanne Schwinning and Lesley DeFalco.

Highlighted publications

Schwinning, S., Meckel, H., Reichmann, L.G., Polley, H.W., Fay, P.A. 2017. Accelerated development in Johnsongrass seedlings (Sorghum halepense) suppresses the growth of native grasses through size-asymmetric competition. PLOS ONE 12, 20176042 pdf

Dammeyer, H.C., Schwinning, S., Schwartz, B., Moore, G. 2016. Effects of juniper removal and rainfall variation on tree transpiration in a semi-arid karst: Evidence of complex water storage dynamics. Hydrological Processes 30: 4568-4581. pdf

Other lab news

The lab welcomes two new graduate students:

Kayla Sustaita will examine the effects of adaptive rotational grazing on soil characteristics.

Logan Maxwell will investigate best restoration practices for abandoned oil and gas exploration fields in Utah.

The lab was awarded two federal grants in 2015:

NSF proposal : DEB-1557176: "Collaborative Research: Hydrological tipping points and desertification of semi-arid woodlands".

The DOD Legacy Award HQ0034-16-2-0006: "Characterizing Mojave Desert shrub ecotypes to establish seed transfer zones for military range restoration".

In the media

In August 2016, Susan was interviewed by Salwa Khan for the Wimberley Valley Radio show "Mothering Earth" Listen to the podcast here.

In September 2013, Susan was interviewed by Alan Knapp on a paper published in Functional Ecology. Listen to the podcast here.

Contact information
Susan Schwinning
601 University Drive
312 Supple Science Bldg
Texas State University
San Marcos, TX 78666, USA
Phone: (512) 245-3753
Fax: (512) 245-8713

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Biology Department
Texas State University

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