Tindall won first prize in a graduate students poster competition!

Congratulations to Tindal Ouverson for winning first prize in the graduate students poster competition at the 2021 Montana State University LRES research colloquium!

Tindall is a master’s of science in Land Resources and Environmental Sciences at Montana State University, working with advisers Drs. Fabian Menalled and Tim Seipel. Tindall and I have been working closely over the past three-ish years on soil microbiomes, and she is preparing to defend her thesis this May.

Check out her recently published paper: Temporal soil bacterial community responses to cropping systems and crop identity in dryland agroecosystems of the Northern Great Plains. 

Tindall’s first paper was accepted!

I’m pleased to announce that master’s student Tindall Ouverson’s first manuscript was accepted for publication!

Photo of woman in front of mountains

Tindall is a Master’s of Science in the Department of Land Resources and Environmental Sciences at Montana State University. Her graduate advisers are Drs. Fabian Menalled and Tim Seipel. Her research focuses on the response of soil microbial communities to cropping systems and climate change in semiarid agriculture. 

I have been mentoring Tindall as a graduate committee member since she began in fall 2019, teaching her laboratory and analytical skills in microbial ecology, DNA sequencing, and bioinformatic analysis. We first met when she came to visit when I was working in Oregon, and since then have connected remotely. She has a flair for bioinformatics analysis, and a passion for sustainable agricultural development. She plans to defend her thesis in 2021, and then to further her career in sustainable agriculture in Montana.

Tindall Ouverson, Jed Eberly, Tim Seipel, Fabian D. Menalled, Suzanne L. Ishaq. 2021. Temporal soil bacterial community responses to cropping systems and crop identity in dryland agroecosystems of the Northern Great Plains.  Frontiers in Sustainable Food Systems.  Article. Invited submission to Plant Growth-Promoting Microorganisms for Sustainable Agricultural Production  special collection.


Industrialized agriculture results in simplified landscapes where many of the regulatory ecosystem functions driven by soil biological and physicochemical characteristics have been hampered or replaced with intensive, synthetic inputs. To restore long-term agricultural sustainability and soil health, soil should function as both a resource and a complex ecosystem. In this study, we examined how cropping systems impact soil bacterial community diversity and composition, important indicators of soil ecosystem health. Soils from a representative cropping system in the semi-arid Northern Great Plains were collected in June and August of 2017 from the final phase of a five-year crop rotation managed either with chemical inputs and no-tillage, as a USDA-certified organic tillage system, or as a USDA-certified organic sheep grazing system with reduced tillage intensity. DNA was extracted and sequenced for bacteria community analysis via 16S rRNA gene sequencing. Bacterial richness and diversity decreased in all farming systems from June to August and was lowest in the chemical no-tillage system, while evenness increased over the sampling period. Crop species identity did not affect bacterial richness, diversity, or evenness. Conventional no-till, organic tilled, and organic grazed management systems resulted in dissimilar microbial communities. Overall, cropping systems and seasonal changes had a greater effect on microbial community structure and diversity than crop identity. Future research should assess how the rhizobiome responds to the specific phases of a crop rotation, as differences in bulk soil microbial communities by crop identity were not detectable.

Paper published on soil microbes, climate change, and agriculture!

I’m pleased to announce that an article was published today on soil microbes, climate change, and agriculture! As local climates continue to shift, the dynamics of above- and below-ground associated bio-diversity will also shift, which will impact food production and the need for more sustainable practices. 

This publication is part of a series, from data collected from a long-term farming experiment in Bozeman, MT, led by researchers at Montana State University with whom I have published several times, including:

In this study, cropping system (such as organic or conventional), soil temperature, soil moisture, the diversity and biomass of weed communities, and treatment with Wheat streak mosaic virus were compared as related to the bacterial community in the soil associated with wheat plant roots.

This paper is open-access, which means anyone can read the full paper.

Dryland cropping systems, weed communities, and disease status modulate the effect of climate conditions on wheat soil bacterial communities.

Ishaq, S.L., Seipel, T., Yeoman, C.J., Menalled, F.D. 2020. mSphere DOI: 10.1128/mSphere.00340-20. Article.


Little knowledge exists on how soil bacteria in agricultural settings are impacted by management practices and environmental conditions under current and predicted climate scenarios.  We assessed the impact of soil moisture, soil temperature, weed communities, and disease status on soil bacterial communities between three cropping systems: conventional no-till (CNT) utilizing synthetic pesticides and herbicides, 2) USDA-certified tilled organic (OT), and 3) USDA-certified organic with sheep grazing (OG).  Sampling date within the growing season, and associated soil temperature and moisture, exerted the greatest effect on bacterial communities, followed by cropping system, Wheat streak mosaic virus (WSMV) infection status, and weed community. Soil temperature was negatively correlated with bacterial richness and evenness, while soil moisture was positively correlated with bacterial richness and evennessSoil temperature and soil moisture independently altered soil bacterial community similarity between treatments.  Inoculation of wheat with WSMV altered the associated soil bacteria, and there were interactions between disease status and cropping system, sampling date, and climate conditions, indicating the effect of multiple stressors on bacterial communities in soil.  .  In May and July, cropping system altered the effect of climate change on the bacterial community composition in hotter, and hotter and drier conditions as compared to ambient conditions, in samples not treated with WSMV.  Overall, this study indicates that predicted climate modifications as well as biological stressors play a fundamental role in the impact of cropping systems on soil bacterial communities.

Paper published on effect of farming systems on soil bacteria!

After several years of bouncing through internal and external review, I’m pleased to announce that the first microbes paper out of the Montana State University Fort Ellis project has been published in Geoderma! The Fort Ellis research has encompassed multiple labs, projects, and many personnel, as it was a large collaboration looking at the effect of different farming systems on biodiversity at the macro (plant), mini (insect), and micro (-be) levels. Spanning multiple years, this project has been a massive undertaking that I briefly participated in but anticipate getting four publications out of (two more are in preparation).

Winter wheat

I previously presented this work at the 2017 Ecological Society of America (ESA) conference (poster: Ishaq et al ESA 2017 poster). And this field soil was the “soil probiotic” that was used in the follow-up greenhouse trial that I ran which was also published this year.

Soil bacterial communities of wheat vary across the growing season and among dryland farming systems.

Ishaq, S.L., Seipel, T., Yeoman, C.J., Menalled, F.D. 2020. Geoderma 358:113989.


Despite knowledge that management practices, seasonality, and plant phenology impact soil microbiota; farming system effects on soil microbiota are not often evaluated across the growing season.  We assessed the bacterial diversity in soil around wheat roots through the spring and summer of 2016 in winter wheat (Triticum aestivium L.) in Montana, USA, from three contrasting farming systems: a chemically-managed no-tillage system, and two USDA-certified organic systems in their fourth year, one including tillage and one where sheep grazing partially offsets tillage frequency. Bacterial richness (range 605 – 1174 OTUs) and evenness (range 0.80 – 0.92) peaked in early June and dropped by late July (range 92 – 1190, 0.62-0.92, respectively), but was not different by farming systems.  Organic tilled plots contained more putative nitrogen-fixing bacterial genera than the other two systems.  Bacterial community similarities were significantly altered by sampling date, minimum and maximum temperature at sampling, bacterial abundance at date of sampling, total weed richness, and coverage of Taraxacum officinale, Lamium ampleuxicaule, and Thlaspi arvense.  This study highlights that weed diversity, season, and farming management system all influence soil microbial communities. Local environmental conditions will strongly condition any practical applications aimed at improving soil diversity, especially in semi-arid regions where abiotic stress and seasonal variability in temperature and water availability drive primary production. Thus, it is critical to incorporate or address seasonality in soil sampling for microbial diversity.

A collaborative paper on zinc and rumen bacteria in sheep got published!

Zinc is an important mineral in your diet; it’s required by many of your enzymes and having too much or too little can cause health problems. We know quite a bit about how important zinc is to sheep, in particular for their growth, immune system, and fertility.  We also know that organically- versus inorganically-sourced zinc differs in its bio-availability, or how easy it is for cells to access and use it.  Surprisingly, we know nothing about how different zinc formulations might affect gut microbiota, despite the knowledge that microorganisms may also need zinc.

This collaborative study was led by Dr. Whit Stewart and his then-graduate student, Chad Page, while they were at Montana State University (they are now both at the University of Wyoming).   Chad’s work focused on how different sources of zinc affected sheep growth and performance (previously presented, publication forthcoming), and I put together this  companion paper examining the effects on rumen bacteria.

The pre-print is available now for Journal of Animal Science members, and the finished proof should be available soon. JAS is the main publication for the American Society of Animal Science, and one of the flagship journals in the field.

Zinc amino acid supplementation alters yearling ram rumen bacterial communities but zinc sulfate supplementation does not.

Ishaq, S.L., Page, C.M., Yeoman, C.J., Murphy, T.W., Van Emon, M.L., Stewart, W.C. 2018. Journal of Animal Science. Accepted. Article.


Despite the body of research into Zn for human and animal health and productivity, very little work has been done to discern whether this benefit is exerted solely on the host organism, or whether there is some effect of dietary Zn upon the gastrointestinal microbiota, particularly in ruminants. We hypothesized that 1) supplementation with Zn would alter the rumen bacterial community in yearling rams, but that 2) supplementation with either inorganically-sourced ZnSO4, or a chelated Zn amino acid complex, which was more bioavailable, would affect the rumen bacterial community differently. Sixteen purebred Targhee yearling rams were utilized in an 84 d completely-randomized design, and allocated to one of three pelleted dietary treatments: control diet without fortified Zn (~1 x NRC), a diet fortified with a Zn amino acid complex (~2 x NRC), and a diet fortified with ZnSO4 (~2 x NRC). Rumen bacterial community was assessed using Illumina MiSeq of the V4-V6 region of the 16S rRNA gene. One hundred and eleven OTUs were found with > 1% abundance across all samples. The genera PrevotellaSolobacteriumRuminococcusButyrivibrioOlsenellaAtopobium, and the candidate genus Saccharimonas were abundant in all samples. Total rumen bacterial evenness and diversity in rams were reduced by supplementation with a Zn-amino-acid complex, but not in rams supplemented with an equal concentration of ZnSO4, likely due to differences in bioavailability between organic and inorganically-sourced supplement formulations. A number of bacterial genera were altered by Zn supplementation, but only the phylum Tenericutes was significantly reduced by ZnSO4 supplementation, suggesting that either Zn supplementation formulation could be utilized without causing a high-level shift in the rumen bacterial community which could have negative consequences for digestion and animal health.

Featured Image Source: Wikimedia Commons

USDA AFRI NIFA Agricultural Production Systems grant awarded to Menalled et al.

In 2016, I was a post-doc in the Menalled Lab, which studies plant and weed ecology in the context of agricultural production and sustainability.  There, I assessed soil bacterial communities under different farming management practices and climate scenarios.  I also helped to develop a grant proposal, which was just accepted by the USDA AFRI NIFA Agricultural Production Systems!  Leading this project is Dr. Fabian Menalled (as Principal Investigator, or PI), along with a number of other PIs; Dr. Amy Trowbridge, Dr. David Weaver, Dr. Tim Seipel, Dr. Maryse Bourgault, and Dr. Carl Yeoman, and collaborators Dr. Darrin Boss, Dr. Kate Fuller, Dr. Ylva Lekberg, and myself as a subaward PI.  I will again be providing microbial community analysis for this project, and collectively the project investigators will bring expertise in plant ecology, agronomy, economics, soil and plant chemistry, microbial ecology, agroecosystems, and more.

This research and extension project focuses on the needs of dryland agricultural stakeholders and it was designed in close collaboration with the NARC Advisory Board. While I was only able to attend one meeting, other team members regularly meet with Montana producers to discuss current issues and identify locally-sourced needs for agricultural research.  During this project, we will continue to meet with the NARC Advisory Board to share our results, evaluate implications, and better serve the producer community.

Diversifying cropping systems through cover crops and targeted grazing: impacts on plant-microbe-insect interactions, yield and economic returns.

Project summary

The semi-arid section of the Northern Great Plains is one of the
largest expanses of small grain agriculture and low-intensity livestock
production. However, extreme landscape simplification, excessive reliance on
off-farms inputs, and warmer and drier conditions hinder its agricultural
sustainability. This project evaluates the potential of diversifying this region
through the integration of cover crops and targeted grazing. We will complement
field and greenhouse studies to appraise the impact of system diversity,
temperature, and precipitation on key multi-trophic interactions, yields, and
economic outputs. Specifically, we will 1) Assess ecological drivers as well as
agronomic and economic consequences of integrating cover crops and livestock
grazing in semi-arid systems, 2) Evaluate how climate variability modify the
impacts of cover crops and livestock grazing on agricultural outputs. Specifically,
we will 2.1) Compare the effect of increased temperature and reduced moisture
on agronomic and economic performance of simplified and diversified systems,
2.2.) Assess the impact of climate and system diversity on associated biodiversity
(weeds, insect, and soil microbial communities) and above- and belowground
volatile organic (VOC) compound emissions, and 2.3) Evaluate how changes in
microbially induced VOCs influence multitrophic plant-insect interactions.


  1. Assess key ecological drivers as well as agronomic and economic consequences of integrating cover crops and livestock grazing in semi-arid production systems
    • Compare the agronomic and economic performance of simplified and diversified systems
    • Assess the impact of cover crops and livestock grazing on the associated biodiversity (weeds, insects, and the soil microbiota)
  2. Evaluate how climate conditions modify the impacts of cover crops and livestock grazing on semi-arid production systems
    • Compare the effect of temperature and soil moisture on agronomic and economic performance of simplified and diversified systems
    • Assess the impact of climate and system diversity on associated biodiversity and above- and belowground volatile organic compound (VOC) emissions
    • Evaluate how changes in VOCs emissions influence important multitrophic interactions such as resistance to wheat stem sawfly and natural enemy host location cues
  3. Integrate the knowledge generated into an outreach program aimed at improving producers’ adoption of sustainable diversified crop-livestock systems

Menalled lab at MSU seeking graduate students

The Menalled lab has MS and PhD opportunities in agroecology, “Diversifying cropping systems through cover crops and targeted grazing: impacts on plant-microbe-insect interactions, yield, and economic returns”.

Last year, I did a post-doc in Dr. Fabian Menalled’s weed ecology lab at MSU exploring the effect of farming system and climate change on bacteria in the wheat rhizosphere.  If you love friendly lab groups, early morning field work, and being outside, then working in the Menalled lab in Bozeman, Montana might be the place for you.

Of course, in Montana, it helps if you also love winter…

What is academic Outreach/Extension?

Service can be a vaguely defined expectation in academia, but it’s an expectation to give back to our community; this can be accomplished in different ways and is valued differently by institutions and departments.  Outreach is an easily neglected part of science, because so often it is considered non-essential to your research.  It can be difficult to measure the effectiveness or direct benefit of outreach as a deliverable, and when you are trying to hoard merit badges to make tenure and your time is dominated by other responsibilities, you often need to prioritize research, teaching, advising, or grant writing over extension and service activities.  Nevertheless, public outreach is a vital part to fulfilling our roles as researchers.  Academic work is supported by public funding in one way or another, and much of our research is determined by the needs of stakeholders, who in this sense are anyone who has a direct interest in the problem you are trying to solve.

Depending on your research field, you may work very closely with stakeholders (especially with applied research), or not at all (with theoretical or basic research).  If you are anywhere in agriculture, having a relationship with your community is vital.  More importantly, working closely with the public can bring your results directly to the people out in the real world who will benefit from it.

A common way to fulfill your outreach requirement is to give public presentations.  These can be general presentations that educate on a broad subject, or can be specifically to present your work.  Many departments have extension specialists, who might do some research or teaching but whose primary function is to connect researchers at the institution with members of the public.  In addition to presentations, extension agents generate newsletters or other short publications which summarize one or more studies on a specific subject.  They are also a great resource for networking if you are looking for resources or collaborations, for example if you are specifically looking for farms in Montana that grow wheat organically and are infested with field bindweed.

For my new job, I’m shifting gears from agricultural extension to building science and health extension.  In fact, the ESBL and BioBE teams at the University of Oregon have recently created a Health + Energy Research Consortium to bring university researchers and industry professionals together to foster collaborations and better disseminate information.  The goals of the group at large are to improve building sustainability for energy and materials, building design to serve human use better, and building microbiology and its impact on human health. I have a few public presentations coming up on my work, including one on campus at UO on Halloween, and one in February for the Oregon Museum of Science and Industry Science Pub series in February.  Be sure to check my events section in the side bar for details.

Even when outreach or extension is not specified in your job title, most academics have some level of engagement with the public.  Many use social media outlets to openly share their current work, what their day-to-day is like, and how often silly things go wrong in science.  Not only does this make us more approachable, but it’s humanizing.  As hard as scientists work to reach out to the public, we need you to reach back.  So go ahead, email us (please don’t call because the stereotype is true: we really do hate talking on the phone), tweet, post, ping, comment, and engage with us!!


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Fort Ellis inoculation day

Today was a big day out in the field at Fort Ellis: virus inoculation day for the project I’ve been part of, on how farming system can alter reactions to adverse growing conditions (like climate change, weed competition, and disease).  This is the second year of the project, and the fifth year of the larger crop rotation study, so a lot is riding on being able to keep to the schedule.

Spring has been cool and wet here in Montana, which has presented us from being able to do work in the muddy fields but hasn’t slowed down the wheat or the weeds.  If the wheat is too developed when the virus is sprayed, the infection won’t manifest well enough to measure.  Thanks to carefully prepared protocols, seasoned personnel, and a stretch of sunny, dry days, we treated our plots and went home early!

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Harvesting a feast of data

My greenhouse trial on the legacy effects of farming systems and climate change has concluded!  Over this past fall and winter, I maintained a total of 648 pots across three replicate trials (216 trials per).  In the past few weeks, we harvested the plants and took various measurements: all-day affairs that required the help of several dedicated undergraduate researchers.

In case you were wondering why research can be so time and labor intensive, over the course of the trials we hand-washed 648 pot tags twice, 648 plant pots twice, planted 7,776 wheat seeds across two conditioning phases, 1,944 wheat seeds and 1,944 pea seeds for the response phase.  We counted seedling emergence for those seeds every day for a week after each of the three planting dates in each of the three trials (9 plantings all together).  Of those 11,664 plants, we hand-plucked 7,776 seedlings and grew the other 3,888 until harvesting which required watering nearly every day for over four months.  At harvest, we counted wheat tillers or pea flowers, as well as weighed the biomass on those 3,888, and measured the height on 1,296 of them.  And this is only a side study to the larger field trial I am helping conduct!  All told, we have a massive amount of data to process, but we hope to have a manuscript ready by mid-summer – stay tuned!

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