Lost in the Corn: The Search for Lysimeters

Today’s guest blog post was provided by summer student intern Laura Lacquement. A native Iowan, Laura grew up south of Des Moines, and went to school at Martensdale-St. Mary’s. She started her college career at Valparaiso University, and later transferred to ISU, where she is now a senior studying Environmental Science.  


I enjoy travelling across the State of Iowa with Water Rocks! and Iowa Learning Farms. The location and events vary, while the field work remains consistent. One of the projects I’ve helped with all summer long is ILF’s cover crop mixtures project. Each week we travel to three of Iowa State University’s research farms to collect water samples from lysimeters located in plots of corn and soybeans.  Each block of plots contains 12 lysimeters placed between rows of corn or soybeans.

Lysimeters measure the movement or storage of water in the ground.  The lysimeters that the ILF team uses are composed of a tube two inches in diameter and two feet (24”) deep.  The bottom of the tube is composed of a porous ceramic cup that allows the movement of water into the lysimeter from the soil around it. Using a vacuum pump, we create suction inside the tube that pulls water inside.  Each week, we extract the water by using a flask that is connected to the vacuum pump on one side and a straw connected to its lid and inserted into the tube to its full depth.  Using the pump and flask, we pull water from the lysimeter into a small bottle, where it will later be analyzed for the amount of nitrates present. Each lysimeter tube is installed so it’s flush with the ground. To protect the lysimeter, a four inch PVC drainage pipe plug and small pipe is placed above it.

Most of our plots are located close to each other, with the exception of the plots at the ISU Northern Research and Demonstration Farm in Kanawha, Iowa. Finding the lysimeters there can be quite an adventure! At the start of the internship, all we could see of corn and soybeans in our plots were little sprouts an inch tall.  In just a couple weeks, the corn grew past our knees to over our heads.  I not only watched this growth, but experienced it firsthand by struggling to carry our devices and tools over and through the corn and soybeans to each lysimeter.

On Friday, June 30, I traveled to Kanawha, Iowa, with Elizabeth to extract water samples from lysimeters there. As I mentioned, the plots here are not located right next to each other, but in completely different fields separated by a grass driveway.  After we collected samples from the soybeans, we entered the corn in search of our small buried lysimeters in the shoulder-height corn.  We walked inside each row looking for our lysimeters … for an hour or so. Our ILF plots happen to be in the middle of a much larger field, and the challenge is that there’s no easy way to flag or label the plots once the corn is this tall! We eventually ventured a bit south of our current location, where we recognized our plots and finally spotted a lysimeter only a short distance away. Small victories!

Friday, July 7, I returned to Kanawha with Kaleb to collect more samples. This time, I knew exactly where to go to find the plot, but not the precise location of the lysimeters. In just one week, the corn had grown from the height of my shoulders to the height of me. I could no longer see over the corn.  As I finished extracting each water sample, Kaleb would move to the next lysimeter.  He may be the tallest of us interns, yet I still could not see him over the corn.  To find him and the next lysimeter, I followed the sound of corn rustling and looked for his bright red shirt through the corn.  If we do not wear bright colored shirts, a game of Marco Polo may be necessary!

After these experiences, I’m now very confident where ILF’s plots at Kanawha are located, plus how to find the other lysimeters and interns in corn taller than me. Each time I take samples from the lysimeters, I have learned a little more about corn and soybean cropping systems, as well as water quality issues in Iowa!

Laura Lacquement

Dirty Hands, Fertile Land: Late Spring Nitrate Testing

My name is Hannah Corey, and I am a sophomore in Agronomy at Iowa State. I was raised on a farm near Lake City, Iowa along with my brothers, some cattle, and a whole lot of corn and soybeans.

MeetTheInterns-HannahI am a soils nerd. I like to read about it, talk about it, and think about it, but most of all I like to get my hands dirty and work with the soil. Thankfully, as an intern for Water Rocks! and the Iowa Learning Farms, I get to do all four! I spent this past week traveling to the Iowa State University Research Farms and collecting soil samples for the Late Spring Nitrate Test. Here’s what I learned…

The Late Spring Nitrate Test is used to determine the amount of nitrate in the soil available to corn plants in late spring when the corn is 6-12 inches tall (we sampled statewide this past week, June 6-10). It’s a straightforward process designed so that farmers can do it in their own fields without much hassle.

The tools of the trade are simple: a soil probe, a clean bucket, and a bag to put the sample in.

Our plots on the research farms are no-till and alternate between single-species cover crop, mixed-species cover crop, and no cover crops. In each plot we pull eight different soil cores and mix them together to form one composite sample. Each core is a standard 12 inches deep and ¾ inch in diameter. We pull cores in a diagonal line across the plot to get a sample that accurately represents the area.


Added bonus: it’s also a great arm workout!

After the samples are bagged and labeled, they are sent to the lab to be analyzed for the nitrate content of the soil. The Iowa Learning Farms team uses this data for research, but with data from their own fields, farmers can also use the Late Spring Nitrate Test in their operations.


A composite sample from the Nashua Research Farm bagged, labeled, and ready to go!

A Late Spring Nitrate Test can tell a farmer how much nitrate is available to their corn, and whether or not they need to apply additional nitrogen fertilizer. If the soil is low on nitrate, farmers can help their corn by supplying the additional nitrogen it needs to grow. If the soil has adequate or high nitrate levels, they can save money and keep nitrates out of the water by refraining from adding excess fertilizer.

To me, the Late Spring Nitrate Test is a win-win-win situation. Proper use of the data collected can help boost corn growth, save money, and improve water quality.

HC-SoilSo dig in, get your hands dirty, and learn about your soil. The more we know about our soil, the more we can do to improve its fertility. After you’ve dug in and your hands are covered in soil, remember, “Dirty hands, fertile land!”

Follow our new #dirtyhandsfertileland series on Facebook and Twitter throughout the summer to learn more about what you can do to improve soil health and fertility!

Interested in learning more about the Late Spring Nitrate Test or having your soil tested? Click on these links to learn more…

Nitrogen Fertilizer Recommendations for Corn in Iowa
(free PDF download from ISU Extension Store)
ISU Extension Specialist Suggests Late Spring N Test For Corn
ISU Soil and Plant Analysis Laboratory

Hannah Corey


2016 Crop Advantage Series kicks off today


Today marks the start of the 2016 Iowa State University Extension and Outreach Crop Advantage Series — these workshops are offered across the state, delivering the latest research, knowledge, and expertise related to crop production.  Topics range from crop weather outlooks for 2016, to soil fertility management, to weed and pest management, conservation practices, and much more!

Several Iowa Learning Farms team members and collaborators will be presenting at select upcoming Crop Advantage Series meetings:

  • Economic benefits of cover crops – Jamie Benning and Liz Juchems
  • Reducing nitrate loss: Scale of practice implementation needed – Matt Helmers and Ann Staudt
  • Genetic selection and seeding rate considerations for tight margins – Mark Licht
  • Spray application strategies beyond glyphosate – Mark Hanna

This year, the Crop Advantage Series meetings are being offered at 14 different locations – 13 across the state of Iowa, plus one in Moline, IL. Check out the map to see which location(s) and date(s) work best for you!

CropAdvantageMapEach Crop Advantage workshop is approved for recertification for Iowa private pesticide applicators, as well as continuing education credits for Certified Crop Advisers (CCAs).

Full registration for each workshop is $60 at the door, with lunch and refreshments included. Many sites still have early registration available online, through the Ag & Natural Resources Extension online portal, for the discounted rate of $50. On the webpage, select the specific meeting location you’re interesting in for additional details and online registration.

Hope to see you there!

Ann Staudt

Food for Thought

As Christmas is now in the past and we turn our minds to 2016, here is a provocative article published in the Washington Post: 10 Things We Should Do to Fix our Broken Food System. Check out the screen shot below for a sneak peek; clicking on the screen shot will take you to the full Washington Post article.

“In this end-of-the-year wrap-up, Tamar Haspel, a food writer for The Washington Post, lays out her 10 things we should do to change a broken food system – 10 changes she says could have a ripple effect, changes that would beget others. She begins with what the government could do: Develop a best-practices standard that could be codified and certified, so farmers who use best practices could attract customers willing to pay more for foods grown that way; Move to crop neutral insurance; Overhaul the Supplemental Nutrition Assistance Program so that it ensures Americans have access to healthful foods; and, Teach food in schools. Next, Haspel addresses what she would like to see food manufacturers do, which is a lot, but she confines herself to two: Use source as a selling point; and, Label everything. As for consumers, she says to vote with your wallet, get closer to food, and cook. Lastly, Haspel looks to farmers, and in this case, looks for a way to give farmers the help they might need to make changes, such as creating a market for crops and animals raised with attention to the rights of farmworkers, the welfare of animals, and the impact on the planet. And create a standard that allows them to charge more for products raised according to higher standards. On the flip side, she says, stop creating incentives for farmers to grow a few commodity crops at a large-scale, and with little thought to environmental repercussions. Finally, everyone, she says, needs to come to the table and engage in a more inclusive, constructive conversation.” – Article Summary by Meridian Institute

Happy New Year!

Jacqueline Comito

An International Perspective on Water Issues

Today’s guest blogger is Iowa Learning Farms/Water Rocks! student intern Kayla Hasper. Growing up on a farm in southeast Iowa (Montrose), Kayla is beginning her senior year at Iowa State University, where she is pursuing a double major in Animal Ecology and Environmental Studies.

I had the opportunity of studying abroad for two weeks in the tropical country of Belize earlier this summer. While hiking through the jungle and snorkeling in the second largest coral reef system in the world, I started to consider the water quality compared to the water quality here in Iowa.

Kayla Hasper participating in an ISU study abroad program in Belize, June 2015

Intern Kayla Hasper participating in an ISU study abroad program in Belize, June 2015

The agriculture in Belize is mainly sugarcane and fruit production, which is less disrupting to the natural environment when compared to our crop production here in Iowa. Sugarcane is a perennial, therefore stabilizing the soil for the three year growth cycle. When the three years is up and new seeds need planted, it requires less tillage than crops in Iowa. Sugarcane also absorbs the necessary nutrients from the groundwater and is tolerant to insects and disease, so it requires little to no pesticides or fertilizers.


Field of sugarcane, one of the most abundant crops grown in Belize

The fruit orchards, which grow pineapple, coconut, plantains, waxy apples, guava, mangos, etc., are left with native plants growing all around the trees so that there is no soil left vulnerable to erosion.

Mangoes trees are a common site across the country of Belize

Mangoes trees are a common site in the country of Belize

While on the inland, I started noticing the ditches full of plastics, tires, and other garbage. I asked our tour guide about the trash that I was noticing. He explained to me that Belize does not have enough money, support, or governmental power to start a recycling program. Each household disposes of their trash on their own. There are designated areas around villages that you can dump your garbage, which are similar to our landfill sites. These, however, are unregulated and end up as piles of garbage right off the highways. The intense rains in the rainy season in Belize wash all of the loose, vulnerable garbage downhill in the watershed.


Designated garbage areas in Belize

He explained, though, that a lot of people in the county of Belize do care about conservation and do what they can to reduce and reuse their consumables. I also believe that the poverty in their culture forces them to become more creative with the little that they do have and to not waste much.

Out on the coast of Belize, the beaches were covered in garbage. The locals explained that the trash on the beaches was actually ocean trash from other countries. The garbage on the beaches also comes from ships that dump their trash loads in the middle of the ocean. (Side note – Water Rocks! has a great video called Isle of Plastic that addresses the challenge of ocean trash. While this song is focused on the Pacific Ocean’s garbage patch, the same principles apply!)

Hopkins, Belize beach filled with garbage that has been washed on shore

Hopkins, Belize beach filled with garbage that has been washed on shore

The second week of my trip, we were staying out on an island that was part of the Turneffe Atoll system. In the Turneffe Atoll, the water was crystal clear and there was no trash in the water or on the beaches. This is partially because the coral reef system is protected, which helps reduce the amount of pollution affecting the area. This is also because the island that we were on was surrounded by many other islands, so the trash couldn’t float directly up to it as easily.

The locals are very concerned, though, about the future impacts of a casino being built on one of the islands in the Turneffe Atoll. The land was purchased before it became a protected area, so the casino is legally allowed to be built. This will have increased environmental disturbance and damage in the area. There will be increased water pollution from the boat traffic, disturbance of aquatic wildlife from the speed and sound of the boats, destruction of wildlife habitat on the island, increased pollution from the trash generated at the casino, etc.

We were given the opportunity to meet some awesome local, as well as international, researchers and conservation advocates while on the atoll. There are many studies being researched and proposals being made about protecting certain delicate areas of the coral reef system. These are areas where there are large populations of dolphins, manatees, fish, etc. that could be negatively affected by the introduction of this casino in the area.

Overall, I could tell that the residents of Belize really care about soil and water conservation. They unfortunately do not have the resources to use the best practices for their lands, but are doing what they can to keep their beautiful country clean.

Based on the amount of funding, research, and support that our state has, I am disappointed in our actions after returning from Belize. The data shows that the amount of nutrients we are letting run downstream and the amount of excess tilling we are doing in Iowa is harmful to our environment, yet many of our farmers/landowners are not doing anything about it. There are great conservation practices that we can be implementing on our land while growing our crops. I also think that farmers/landowners should raise a larger diversity of crops and livestock on their land.

Kayla Hasper

Guest Blog: Behind the Scenes with Water Sampling, Part I

Today’s guest blogger is Iowa Learning Farms/Water Rocks! student intern Mikayla Edwards. Originally hailing from the Anamosa area, Mikayla is beginning her senior year at Iowa State University, pursuing a degree in Animal Ecology.

Three hours away, there is a faraway land that we like to call the Southeast Research Farm at Crawfordsville. In that faraway land our Iowa Learning Farms program has placed fancy tubes two feet into the ground. These tubes are called lysimeters. Lysimeters have a vacuum seal and collect the infiltrated water from the surrounding ground.

In Iowa, nitrates from agricultural lands are a hot topic regarding water quality. Nitrates are dangerous to infants, the ill, and the elderly when they reach drinking water in high quantities. Farmers are using various techniques to prevent nitrate loss to the water for many reasons. Crops need the nitrates, they cost a lot of money, and they are no good in the water, especially when they reach the Gulf of Mexico and cause a huge algal bloom in what’s commonly referred to as “The Dead Zone.”

As part of our National Conservation Innovation Grant cover crop mixtures project, our program is using these lysimeters to test the water’s nitrate levels in corn/soybean fields with different forms of cover: single species cover crop, cover crop mixture, and no cover. Water is collected biweekly from the Southeast Research Farm and four others around the state to see how the different levels of cover are affecting the nitrate levels in the water. Visually, the sites all look pretty similar other than the different covers. A couple areas in each plot still have cover crop remnants but the only thing in the other areas is this year’s crop, either corn or soybeans.

This is what a lysimeter looks  like from the surface.  Sometimes they are covered  completely or just partially  depending on what has  happened in the field lately.

This is what a lysimeter looks like from the surface – notice the white PVC cap protecting the lysimeter inside. Sometimes they are covered completely or just partially depending on what has happened in the field lately.

This is what the lysimeter looks like once the protective cap has been removed. The O ring holding the bend is removed and then a small tube from the collection flask is threaded through the top of the rubber opening at the top of the tube.

This is what the lysimeter looks like once the protective cap has been removed. The O ring holding the bend is removed and then a small tube from the collection flask is threaded through the top of the rubber opening at the top of the tube.

Collecting the water samples is not a difficult task. All that has to be done is open a small tube that has been bent to hold the vacuum seal, attach a vacuum pump to a collection container, feed an even smaller tube from the collection container into the lysimeter, give the vacuum a few pumps and wah-lah! Assuming there is a sample, water will quickly start flowing into the collection container.

Once the tube is all the way to  the bottom of the lysimeter and  a vacuum is applied, a sample  fills the collection flask!

Once the tube is all the way to the bottom of the lysimeter and a vacuum is applied, a sample fills the collection flask!

After the sample is collected, there are a few other steps to be completed. First, the sample must be emptied into a clean plastic bottle and labeled with the lysimeter number, location, date, and level of cover. Any leftover sample water is dumped a few feet away from the lysimeter to prevent it from going right back in. Next, deionized water is used to clean the collection container and tube. This is done by putting the tube into a bottle of the deionized water and giving the vacuum a few pumps so the water flows through the tube and is then swished around the collection container and also dumped a few feet away.

Once the sample is emptied into a bottle and labeled, the collection flask and tubing must be cleaned with deionized water, aka DI water, to prevent any contamination from one sample to the next.

Once the sample is emptied into a bottle and labeled, the collection flask and tubing must be cleaned with deionized water, aka DI water, to prevent any cross contamination from one sample to the next.

Lastly, the vacuum seal must be reapplied so that a new sample can be obtained over the next couple weeks. For this, the vacuum pump is attached directly to the lysimeter and 60 psi of pressure are applied. An O ring is then placed over a bend in the tubing so that the vacuum stays sealed in.

After everything is cleaned, the vacuum  is reapplied to the lysimeter so that a  sample will be collected over the next  two weeks for testing!

After everything is cleaned, the vacuum is reapplied to the lysimeter so that a sample will be collected over the next two weeks for testing!

So, that is the process for one lysimeter and there are 24 at each research farm. The whole process takes about two hours depending on how many samples there are, which is affected by the amount of rainfall there has been. Lately, we have had a lot of rain so we have been getting 20-24 samples from each farm! For comparison, when we started back in May, we were only getting around 15 because of the dryness.

So, that is how a lysimeter water sample is collected! But that’s not all we have to do! The three hour drive home must be repeated and then the data must be entered into the electronic database when we get back to campus. We record which lysimeters had samples and they are given a new sample ID number. Then the labels are taped on to prevent any damage and they are placed in a cooler until they can be sent to the lab for testing.

The whole process is actually pretty fun when you work with fun people; good conversations are always had with fellow interns. The tan lines though, they are pretty atrocious!

Mikayla Edwards