Category: Data Nugget | Data Nuggets

6.13.25

What grows when the forest goes?

Area of the H.J. Andrews Experimental Forest in Oregon, a few years after a fire.

The activities are as follows:

The H.J. Andrews Experimental Forest, or Andrews for short, is a long-term ecological research site in the Cascade Mountains of Oregon. The forest is a temperate old-growth rainforest. It is known for its lush and green understory of flowering plants, ferns, mosses and a towering canopy of Douglas fir, Western hemlock, Red cedar, and other trees. Scientists have spent decades studying how plants, animals, land use, and climate are all connected in this ecosystem.

Matt is a biology teacher who has spent two summers in the field working with scientists at the Andrews. These experiences have been valuable ways to bring real data and research back to his students! Matt works closely with Joe, a scientist who studies the impact of disturbances on plants, such as fires.

Historically, large, severe fires have been a part of the ecology of forests in Oregon. They typically occur every 200-500 years. Many of the plants at the Andrews Forest are those that can deal with fire. Fires clear out dead plants, return nutrients to the soil, and promote new growth of understory and canopy plants. With climate change impacting temperature and rainfall across the globe, forests in Oregon are increasingly experiencing longer periods of dry and hot weather. These changes are causing an increase in the frequency and severity of wildfires.

On Matt’s last day at the Andrews in 2023, a lightning strike started a wildfire in a far corner of the forest. With hundreds of firefighters on the ground and several helicopters in the air, the “Lookout Fire” burned for several months, consuming about 70% of the Andrews forest!

Plots in 2023 being surveyed for native and invasive plants to calculate the proportion that are invasive after a burn.

When Matt returned in the summer of 2024, it looked nothing like the forest he had left. The fire completely changed the course of his research experience. When he saw the scorched forest, he began to wonder how it would recover. He also observed that the fire had not burned at the same intensity throughout the forest. Some areas of Andrews were burned more, and in some spots, the fire had been less intense.

Matt thought that some plants may do better after a severe burn, while other species might do worse. Specifically, Matt wanted to see whether native and invasive plants would show differences after a fire. Plants that have historically grown in an area without human interference are called native plants. These plants have a long history of adapting to the specific conditions in an area. When a plant species is moved by humans to a new area and grows outside of its natural range, it is called an invasive plant. Invasives often grow large and fast, taking over habitats, and pushing out native species. Invasive plants tend to be the ones that can grow fast and handle disturbances, so the team expected that invasive species would recover more quickly than native plants after high severity fires.

It was still too early to re-enter the areas burned by the Lookout Fire, so Matt and Joe chose another recent fire. They used data collected from a section of the forest that had burned in 2020. In 2021, a year after the fire, scientists put out 80 plots that were 1m²in size to collect data on the understory plants.

Each section was given a burn severity value based on the amount the canopy trees had burned directly over the plot. Scientists would look up at the tree canopy and see how much was missing, and the more that was gone, they knew the burn severity had been higher. Scientists then identified every species of plant in the plots and counted the number of individual plants of each species. This was repeated every year after 2021 to observe changes over time. Matt and Joe decided to analyze data from 2023, which Matt helped collect when he visited. To answer their question, they calculated the proportion of invasive plants in each plot.

Featured scientists: Joe LaManna (he/him) from Marquette University and
Matt Retterath (he/him) from Fridley Public Schools.

Flesch–Kincaid Reading Grade Level = 4.3

Additional teacher resources related to this Data Nugget:

There are two blog posts written about the Andrews LTER research featured in this activity.

https://lternet.edu/stories/fire-brings-new-perspectives-on-disturbance-at-h-j-andrews-experimental-forest/
https://lternet.edu/stories/burned-forest-bleached-reef-lter-sites-adapt-to-learn-from-disturbance/

5.30.25

CO2 and trees, too much of a good thing?

The activities are as follows:

Kristina conducting the tree survey, measuring the size of a tree, which will later be used to calculate the mass of carbon in that tree.

The amount of carbon dioxide (CO2) in the atmosphere has steadily increased since the start of the Industrial Revolution in 1750. This extra CO2 traps heat like a blanket, causing the global climate to warm. The resulting climate change effect is known and widely accepted in science. While scientists are certain that climate change is happening, they still have many questions about its impacts.

For example, scientists today are exploring whether climate change will help or hurt trees and forests. Many scientists think that elevated CO2 in the atmosphere can actually help trees. We can see why in the formula for photosynthesis:

6𝐶𝑂₂+6𝐻₂𝑂+𝐸𝑛𝑒𝑟𝑔𝑦→𝐶₆𝐻₁₂𝑂₆ +6𝑂₂

Carbon Dioxide + Water + Energy (sunlight) → Glucose + Oxygen

If you add more CO2 to the atmosphere, trees will have more resources for photosynthesis and can make more glucose. Glucose is food for the trees. Trees can use their glucose for growth, using it to make wood. However, trees sometimes have to put glucose towards other things. Just like us, plants break down glucose for energy through cellular respiration:

C₆𝐻₁₂𝑂₆ +6₂→ 6𝐶𝑂₂+6𝐻₂𝑂+𝐸𝑛𝑒𝑟𝑔𝑦
Glucose + Oxygen → Carbon Dioxide + Water + Energy (ATP)

Two large trees stand in the experimental plot after a survey. The tree to the right has been banded to measure its growth.

Trees need energy for everyday functioning, or to respond to stress. Under climate change, trees might experience more stress. Stress for trees might increase if summer temperatures get too hot, or they don’t have enough water. More stress means more respiration and less growth. Or, even worse, the trees could die. Dead trees can’t photosynthesize, and they also decompose, which releases CO2 into the atmosphere
as microbes break down wood and other materials.

Kristina and Luca are scientists looking at the effects of climate change on trees. They wanted to test whether climate change was benefitting or hurting trees. They set out to find some data that would allow them to test these alternative hypotheses.

A dead ash tree stands in the experimental plot after a survey. The carbon in this tree
will return to the atmosphere through decomposition.

Kristina runs a tree census in a forest at the Smithsonian Conservation Biology Center in Virginia. Since 2008, she and many other scientists have surveyed every tree in their 26-hectare plot. Every five years, they count up how many trees are alive, how much they’ve grown, and how many have died. Luca joined Kristina’s lab in 2022. He and Kristina worked together with many other scientists to collect and process data on tree growth and mortality in 2023.

They used this growth and mortality data for individual trees to calculate levels of carbon gained and lost by the whole forest. The amount of carbon used for growth across the whole forest was measured as the mass of carbon gained. They also calculated the weight of the trees that died, which was measured as the mass of carbon lost. Both of these measurements were calculated in megagrams (Mg, that’s one million grams) of carbon (C) per hectare (ha) of forest per year (yr), or (MgC/ha/yr). The difference between these
two values is the change in carbon. This value gives the balance between carbon gained and lost. A positive value means there is more carbon being taken in by the forest than lost, and a negative value means that more carbon is being lost back to the atmosphere.

Featured scientists: Kristina J. Anderson-Teixeira (she/her) & Luca Morreale (he/him) at Smithsonian’s National Zoo & Conservation Biology Institute. Written by Ryan Helcoski

Flesch–Kincaid Reading Grade Level = 7.8

5.14.25

PFAS: Our forever problem

Gary during his research experience with Natalia.

The activities are as follows:

Per- and polyfluoroalkyl substances (PFAS) are a group of pollutants that are found in many commonly used products. They are in clothing, non-stick pans, and even the linings of cans and other food containers. Because PFAS are used in so many everyday products, they make their way into the environment. Once these compounds are in our environment, they will be there for up to a thousand years! For this reason, PFAS are known as “forever chemicals.”

Water is a very common place to find these forever chemicals. Normal water treatment processes do not remove PFAS from our drinking water. Consequently, PFAS are found in the blood of humans and animals worldwide. In humans, they have been shown to cause liver damage, cancer, harm immune systems, and other health issues.

Natalia is a researcher at Florida International University who studies PFAS and other chemicals in the environment. She wanted to make sure she shared her work with the public, as this topic is so important for us all. She thought one way to do this would be to work with local teachers.

Gary, a science teacher at a school nearby, joined Natalia’s lab for the summer. When the opportunity became available, Gary jumped at the chance to investigate and learn more about Florida’s amazing environment and work in the field with scientists. He was so excited because Natalia had appeared on TV and radio shows and had authored articles in leading science magazines. When they met, Natalia described PFAS to Gary, and he was immediately captivated.

Gary and Natalia decided to work together to explore PFAS in Biscayne Bay. This area is a crucial estuary around Miami, providing a unique environment that supports diverse wildlife and local industries. As a young person, Gary would go shrimping along the bay. He really enjoyed the natural beauty of such a precious resource right in his backyard. Unfortunately, today, Biscayne Bay faces numerous
environmental challenges.

Map showing Gary’s research sites where he sampled PFAS

One challenge is PFAS, which enters the estuary through water pollution that drains into the bay. Gary expected PFAS to be highest in the urban freshwater streams that drain into the bay because human activity is high, and a lot of chemicals are released into the water. He thought that the bay would also have high concentrations of PFAS because the streams drain into the bay, but the surrounding land limits the water from mixing with the ocean. Once the water makes it to the ocean, the chemicals should be able to mix with the larger body of water, lowering the concentration of PFAS.

Gary and Natalia identified 16 water sampling sites in water bodies near Miami. They broke these sites into three categories: (1) freshwater rivers that bring water from urban areas into the bay, (2) brackish water, which means a mixture of freshwater and saltwater, located within Biscayne Bay, and (3) salt water found in the Atlantic Ocean. Courtney, a graduate student in Natalia’s lab, joined the team to assist Gary with collecting data and using the technical instruments needed to analyze the samples. Together, they collected one 500 mL sample from each site. To ensure accuracy in the collection of data, they collected two samples from the South Beach pump station site. Gary and Natalia brought the samples back to the lab and ran the samples through instruments that measured PFAS levels. Gary predicted that he would find high levels of PFAS in the freshwater canals and the brackish water of Biscayne Bay, but less in the open ocean.

Featured scientists: Gary Yoham from Miami Senior High School with Natalia Soares Quinete and Courtney Heath from Florida International University

Flesch–Kincaid Reading Grade Level = 7.3

4.18.25

Farms in the fight against climate change

Caro working in the labs at the Kellogg Biological Station to confirm the % soil carbon measurements used in the study.

The activities are as follows:

Carbon, when it is found in the soil, has a lot of benefits. Soil carbon makes water more available to plant roots, supports microbes and insects, helps water move through the soil and not flood at the surface, and holds on to critical nutrients for plants, like nitrogen and phosphorus. It is a key measure of soil health used by farmers.

The more carbon stored in soils, the less that ends up in our atmosphere as greenhouse gas, which contributes to climate change. Farming practices that increase soil carbon are a double benefit – they help crop plants grow and produce more return for farmers, while also helping to fight climate change.

Yet, accumulating carbon in the soil is a slow and mysterious process. It can take decades to see greater levels of carbon in most agricultural soils. Farmers need information about which farming practices reliably and continually increase soil carbon.

View of the Long-Term Ecological Research experiment at the Kellogg Biological Station where plots have been growing with different agricultural and plant community treatments since 1989.

Caro is a soil scientist working with farmers to figure out how they can increase carbon in their soils. Her passion for soils brought her to the Kellogg Biological Station. This site is very special because it houses the Long-Term Ecological Research Program, which has been running the same experiment since 1989! When the study began, the soils were the same across the site. But, after decades of different treatments taking place in research plots, a lot has changed above and below ground.

In 2013, a team of scientists worked to sample soil carbon at this site, 25 years after the experiment began. The team processed the samples to determine the percent, by weight, of each soil sample that is made up of carbon. This is called % soil carbon. They collected samples from 4 different treatments, each with 6 replicate plots:
(1) Conventional: plots grown in a corn soybean-wheat crop rotation. The soil in these plots is tilled during spring, meaning they are disturbed and turned over. These plots represent how agriculture is conventionally done in the area with standard chemical inputs of fertilizer, herbicides, and pesticides.
(2) No-till: plots that are grown in the same way as conventional, but with one key difference. The soil in these plots is not tilled, meaning it has been undisturbed for 25 years at the time of sampling.
(3) Cover crops: plots grown similarly to conventional, with a few key differences. First, cover crops were added. Cover crops are plants that are planted alongside crops or at times of the year when the main crop is not growing. This means the soil has living plant roots year-round, not just during the season with crops. Second, this treatment had no chemicals added; all nutrients came from the addition of manure. These plots were tilled.
(4) Not farmed: non-agricultural plots growing in a diverse mix of plant species. Plots are unmanaged, but are sometimes burned to keep out woody species.

These 4 treatments represent different ways that land can be managed. The goal of the study was to see how different types of land management had changed % soil carbon over time. When Caro came to KBS in 2018, she was excited to see such a cool dataset waiting to be analyzed! She thought that keeping the soil undisturbed and having living roots in the soil for more of the year would increase soil carbon over time. This led her to predict that she would see higher % spoil carbon in the cover crop and no-till treatments, compared to conventional.

Featured scientist: Caro Córdova from University of Nebraska-Lincoln and the W. K.
Kellogg Biological Station Long Term Ecological Research Program.

Flesch–Kincaid Reading Grade Level = 4.1

Additional teacher resources related to this Data Nugget:

The results from this study are published and the article is available online.
Table 2 in the paper matches the dataset that students are working with in this activity.

If students want to read more about this paper, there is a blog post summarizing the study.

The full dataset is also available online in the Dryad Digital Repository. The file has lots of details about the variables measured and the different cropping systems studied. The first tab of the spreadsheet contains the data used in this activity, plus many more variables and treatments that students can explore to ask new questions!

More information on Regenerative Agriculture from MSU here.

These data are part of the Kellogg Biological Station Long Term Ecological Research Program (KBS LTER). To learn more about the KBS LTER, visit their website.

3.18.25

Reconstructing the behaviour of ancient animals

Holly working with a skull fossil before it is scanned.

The activities are as follows:

Fossils are the ancient remains of organisms that existed thousands to millions of years ago. Scientists look through fossil records to learn about the lives of animals and plants that are extinct today. Fossils can hold clues about the environment, how species interacted with each other, what they ate, and even how they acted.

Holly found her first fossil at 6 years old when she visited a beach in the United Kingdom. It was a small piece of ancient coral. She thought it was amazing to see a remnant of how something looked over 350 million years ago! Holly loved that fossils allowed her to time travel and explore ancient worlds. She pursued her passion and today is a paleobiologist, or scientist who uses the fossil record to learn more about the biology of past organisms. This career has given her the opportunity to study thousands of fossils from many species, from dinosaurs to ancient humans. She has traveled all over the world, including Europe, North America, Asia, and Australia!

Holly specializes in using fossils to paint a picture of the lifestyles of ancient animals. She uses the shape, structure, damage patterns, and burial poses of bones, and compares them to modern bones. By using what we know about living species, Holly can reconstruct the life and death of ancient organisms.

Recently, Holly teamed up with Mary, Sergi, Ingrid and Adam, because they were all scientists curious about the same species – an extinct primate called Mioeuoticus (phonetic: my-o-you-otikus). This animal is believed to be a relative of modern lorises. Lorises that are alive today live in the treetops of tropical forests in India, Sri Lanka, and southeast Asia. Lorises move very slowly and are nocturnal, which means they are typically active at night.

Holly and her colleagues wanted to know whether Mioeuoticus were nocturnal like their loris relatives. By reconstructing the behaviors of related species through time, the team can map out whether the ancestors of modern species behaved the same way since their origin.

There are a few traits from an animal’s skull that can serve as clues. For example, nocturnal animals typically have larger eyes to increase their ability to see at night. Therefore, animals that have proportionally larger orbital cavities, or eye sockets, are likely to be nocturnal.

There is only one Mioeuoticus skull in the whole fossil record! To answer their question, the research team first measured the orbital cavities of the fossil. They used a computer software program designed to precisely measure 3-dimensional scans of bones. Using this technology, Holly obtained the diameter and area of the Mioeuoticus orbital cavities.

Left) CT scan of *Mioeuoticus* cranium. Right) The same cranium with the optic foramen (through which the optic nerve connects the eye to the brain) is highlighted in red and the orbital cavity is highlighted in green.

They then had to compare the fossil values to values of modern species that are alive today. To do this, the team looked through published data collected by other scientists. They found values for the same features in nocturnal lorises and other primate groups. They compared the value from their fossils to three primate groups:

diurnal – active during the day
cathemeral – active during both the day and night
nocturnal – active at night.

In order to compare primates with different body sizes, the team used an index that looks at relative orbital size. This index uses an equation to scale the orbital measurements relative to body size. If Mioeuoticus were nocturnal, Holly predicted the relative orbital size to be similar to the strepsirrhines that have been observed to be nocturnal because this group includes the closest living relative, the lorises.

Featured scientist: Holly E. Anderson (she/her) from Warsaw University, Poland Collaborating scientists: Mary Silcox, Sergi López-Torres, Ingrid Lundeen, & Adam Lis

Flesch–Kincaid Reading Grade Level = 10.1

Additional teacher resources related to this Data Nugget:

Check out this publication related to the research in this activity:

Anderson, H. E., Lis, A., Lundeen, I., Silcox, M. T., & López-Torres, S. 2025. Sensory Reconstruction of the Fossil Lorisid Mioeuoticus: Systematic and Evolutionary Implications. Animals: 15(3), 345. DOI: 10.3390/ani15030345

1.20.25

Microbes facing tough times

Jennifer sampling soil before the shelters were set up. Here you can see the control (left) and carbon addition (right) plots.

The activities are as follows:

As the climate changes, Michigan is expected to experience more drought. Droughts are periods of low rainfall when water becomes limiting to organisms. This is a challenge for our agricultural food system. Farmers in Michigan will be planting crops into conditions that make it harder for corn, soybean, and wheat to grow and survive.

Scientists are looking into how crop interactions with other organisms may help. Microbes are microscopic organisms that live in soils everywhere. Some microbes can help crops get through time times. These beneficial microbes are called mutualists. They give plants nutrients and water in exchange for carbon from the plant. Microbes use the carbon they get from plants as food. If plants are stressed and don’t have any carbon to give, microbes get carbon from dead plant material in the soil.

Jennifer is a biologist studying the role of microbes in agriculture. She has always been interested in a career that would help people. As a student, Jennifer thought she would have a career in politics. Along the way, she learned that a career in science is a great way to study questions that may lead to solutions for the challenges we are facing today. Jennifer was drawn to the Kellogg Biological Station, where she joined a team of scientists studying the impacts of climate change and drought on agriculture.

Jennifer and other scientists set out to test ways that we can give mutualists in the soil a boost. She thought, perhaps if we were to give microbes more food, they would be less stressed during a drought and would be able to help out crops growing in these stressful conditions.

To test this idea, Jennifer needed to test how well microbes were doing under different carbon and drought conditions. First, she set up treatments in soybean fields to manipulate the amount of carbon in the soil. She set up control plots where she left the soil alone. She also set up carbon treatment plots where dead plant litter was added to the soil to increase the carbon available to microbes.

Next, Jennifer manipulated the availability of water in her plots to test the microbes under stress. To do this, she set up her plots under shelters that kept out rain. The shelters had sprinklers, which were automated to add specific amounts of water to the plots. This design allowed Jennifer to control the watering schedule for each plot. One shelter treatment was a control, where water was added to the plots every week. This is similar to the schedules of local farmers who add water through irrigation. The other shelter treatment was drought, where plots received no water for six weeks. This experiment was replicated 4 times, meaning there were 4 shelters on the control watering schedule and 4 shelters that were under drought conditions.

A view of one of the shelters used in Jennifer’s experiment.

Finally, Jennifer had to measure how the microbes were doing in each treatment. She did this by measuring their enzyme activity. Enzyme activity is a measure of how active the microbes are. The higher the enzyme activity, the happier the microbes are. To measure this, Jennifer collected soil samples from each plot throughout the growing season and took them to the lab to measure enzyme levels in the soil samples. These enzymes are made by microbes when they are active. She then calculated the mean of all her samples for each treatment combination.

Jennifer predicted two things. First, if drought is harmful to microbes, then she would expect to see lower enzyme activity in the drought treatment compared to the irrigated treatment. Second, if adding carbon to the soil is a way to help microbes overcome the challenge of drought, she expected higher enzyme activity in the plots with plant litter added compared to the control treatment. Both of these taken together would indicate that drought is stressful for microbes, but we can help them out by adding resources like plant litter to soils.

Featured scientist: Jennifer Jones (she/her) from the Kellogg Biological Station Long Term Ecological Research Site. Written with Melissa Frost and Liz Schultheis.

Flesch–Kincaid Reading Grade Level = 8.2

Additional teacher resources related to this Data Nugget:

To introduce this Data Nuggets activity, students can watch a talk by Jennifer when she made a classroom visit to share her background and research interests. This video is a great way to introduce students to scientist role models and learn more about what a career in science looks like, as well as get an introduction to the themes in the research.

There is also a video of Jennifer and her scientist colleague, Grant Falvo, out in the field talking about their research under the rainout shelters.

For more information about the rainout shelter experiment, students can watch this short video featuring Jennifer Jones and another scientist on the team, Grant Falvo:

These data are part of the Kellogg Biological Station Long Term Ecological Research Program (KBS LTER). To learn more about the KBS LTER, visit their website.

1.9.25

Do you feel the urban heat?

Attaching a heat sensor to a street sign in Miami to monitor urban temperatures.

The activities are as follows:

Record-breaking temperatures climb higher every year, and Florida is no exception. In Florida, the impact of climate change is felt mostly during the hurricane season. Storms are becoming more violent and show up earlier in the season. These extreme temperatures and weather events affect living organisms of all types, including humans. Outdoor workers, the elderly, and all people who lack adequate housing are susceptible to temperature changes in the environment.

Heat sensor ready to be put out into the city.

Irvin teaches science at a high school in Miami, Florida. On his way to work, he listens to a local radio station to catch up on the news. One day the radio hosts were talking about an increase in homelessness in Miami and other cities. They also brought up the record heat that the U.S. was experiencing and how this may affect those without homes. This conversation on the radio made Irvin think. He reflected on the impact that such high heat could have on individuals who sleep without air conditioning.

This inspired Irvin to learn more about what could be done to mitigate the impact of climate change in his city. Irvin joined a program that invites teachers to work in scientists’ labs in the summer to gain research experience. Irvin was matched with Tiffany, a scientist interested in how urban heat can change based on structures like concrete buildings, urban dwellings, and unshaded places. Irvin took this opportunity to explore how high temperatures in Miami affect the daily lives of people living there. First, Irvin started looking into how temperatures are reported in Miami. He learned that there was just a single sensor stationed at the nearby airport. The heat and humidity readings from this one sensor are used by local officials to alert the entire city about dangerous heat levels. Alerts are issued when the heat index reaches 108 degrees Fahrenheit or higher. Heat index is a value that represents how the body feels temperature when humidity is factored in. With these alerts, people can take action by spending less time outside.

Teachers visiting the mangroves in Miami on a record heat day.

Irvin realized that no matter how reliable the sensor at the airport is, there is likely a larger range of temperatures within the city. He wanted to know whether the temperatures at the airport were similar to the heat felt at places where people spend time outside.

Tiffany’s research team had already started to collect temperature data in urban places where they hadn’t been recorded before. Since 2018, her lab placed hundreds of small heat sensors around the city. The sensors go out for 3 months and then the team collects them, records their data, and places them back out into new areas of the city.

Irvin wanted to compare areas that varied in coverage from the sun. He focused on sites where people gathered and spent long periods of time outside – bus stops. Some of the sites he chose had shade from trees, some had a roof providing partial sun cover, and other sites were totally exposed with no shade. Irvin took photos of each bus stop and used them to classify all sites as either full coverage, partial coverage, or no coverage. He used data from the airport as a control comparison to his bus stop sites.

Featured scientists: Irvin E. Arce (he/him) and Tiffany Troxler (she/her) from Florida International University

Flesch–Kincaid Reading Grade Level = 9.6

12.20.24

Does the heat turn caterpillars into cannibals?

Kale in the lab setting up an experiment with fall armyworms.

The activities are as follows:

Around the world, temperatures are rising from climate change. This is a hot topic for scientists because warmer temperatures could make diseases spread a lot faster. Many diseases spread by the foods we eat. With warmer temperatures, metabolisms increase, and organisms need to eat more food to survive. This increases the risk of eating something that will get them sick.

When Kale started graduate school, they joined a lab that studies how climate change affects the spread of disease in fall armyworms, a type of caterpillar. Fall armyworms are an agricultural pest known for destroying corn, soybeans, and other crops worldwide. In the summer, they move into fields and rapidly chow down on crops. It’s often reported by farmers that it seems as though fall armyworms can remove all the leaves from a cornfield overnight! Believe it or not, their huge appetite leads them to another food source – they will even turn into cannibals and eat each other!

Once Kale started graduate school, they became interested in how cannibalism can increase disease spread in warmer temperatures. Fall armyworms can get infected with a special type of virus called a baculovirus. Baculoviruses are a group of viruses that infect insects, especially caterpillars. They are highly specialized, meaning that each baculovirus usually only infects one species.

A fall armyworm that has been liquified due to a baculovirus infection.

If a fall armyworm eats a fellow fall armyworm that is infected, it can be deadly. In fact, the disease causes their body to completely liquify into a puddle of pure virus! This baculovirus is so effective that farmers even use it to help control infestations in their fields. Since this specific baculovirus only infects fall armyworms, it is safe to use on crops without worrying about effects on humans or other living things.

To study how cannibalism can affect disease spread, Kale designed a set of experiments. They thought that when temperatures are higher, the larvae’s metabolism would increase and make them hungrier caterpillars. Increased appetite could then lead to more cannibalism. As a result, more larvae would be eating others that are infected, further spreading the deadly baculovirus.

To test these ideas, Kale set up small Petri dishes and placed one big fall armyworm in each dish as the focus of each trial. Kale added a piece of insect food and a smaller fall armyworm to each dish. This way, the larger caterpillars had the option of eating the insect food, cannibalizing its smaller friend, or munching on both.

To see if temperature had an impact, Kale set up three treatments at low, medium (ideal), and high temperatures. They assigned 40 Petri dishes to each temperature. To test changes in disease transmission, half of the smaller caterpillars were infected with baculovirus, and half remained uninfected.

Kale predicted that fall armyworms at higher temperatures would cannibalize more because they need more food to keep up with an increased metabolism. They also predicted that fall armyworms that eat an infected caterpillar would be more likely to become infected at higher temperatures.

Featured scientists: Kale Rougeau from Louisiana State University

Flesch–Kincaid Reading Grade Level = 10.2

Additional teacher resources related to this Data Nugget include:

You can also watch a time-lapse video of Kale in the lab to get a glimpse of their work. Follow along as they check fall armyworm cadaver samples for baculovirus infection using a microscope

Kale also provided a video of baculovirus lysing, where occlusion bodies that encapsulate the virus are dissolved, confirming the presence of infection in the fall armyworm sample.

Read more about Kale’s hobby of participating and training for dog competitions on the Beyond the Bench blog.
More about fall armyworms here and here.

12.11.24

Little butterflies on the prairie

Butterfly on prairie flower. — A Tiger Swallowtail butterfly visiting a prairie flower to drink nectar.

The activities are as follows:

Butterflies are insects with colorful wings. You will often see them in a field, flying from flower to flower. Butterflies eat a sugary food made by flowers, called nectar. In return, the butterflies help the plants make seeds by moving pollen. As they travel from flower to flower, pollen is dropped off. This helps plants reproduce and make seeds. This is called pollination, and butterflies are pollinators. We need pollinators to grow many of the fruits and vegetables that we eat!

Prairies are habitats filled with many types of flowers. The Midwestern United States used to be covered in prairies. Today, most have been replaced by farm fields. Crops like corn and soybeans are commonly planted in the Midwest. Farm fields are important because we need land to grow our food. But this also means there is less food and habitat for butterflies.

Many farmers are concerned with growing our food while still protecting habitat for butterflies and other species. They want to know – how can we grow food for ourselves while still growing flowers for butterflies? A group of scientists in Michigan is working with farmers to think of solutions. The team is made of people from many different backgrounds and work experiences. The members of the team change over time, but typically 8 scientists are working together at a time. They all come together to brainstorm and do their research at the Kellogg Biological Station in Michigan.

Group of researchers ready to go out into field to butterfly survey. — Members of the Haddad Lab, ready to go out for a day of butterfly sampling in the prairie strips!

Prairie strips are a new idea that might help both farmers and the environment. These strips are small areas of prairie that can be added to farm fields. They look like rows of flowers and grasses within a field. They create habitat for many species, like butterflies, birds, ants, and even microscopic fungi and bacteria! Prairie strips may also help our food grow better by providing habitat for pollinators.

To figure out if prairie strips are able to draw in butterflies, the research team needed to collect data. They visited a large experiment that had many different kinds of farm fields. Some of the fields had prairie strips, while others did not. They thought prairie strips would help butterflies by adding habitat for them in farm fields that usually don’t have many flowers. They predicted they would see more butterflies in fields that have prairie strips and fewer in fields without these strips.

To count the butterflies in each type of field, the team went out on sunny spring and summer mornings when butterflies were flying around and eating nectar. They walked along the same paths in the same fields at the same time every week. Each time, they counted all the butterflies they saw within 5 meters. Each walk was 12 minutes long and followed a 150-meter path. They did these counts in 6 farm fields without prairie strips and 6 farm fields with prairie strips. The team counted butterflies like this 20 times over the summer. At the end of the summer, they added up all of the butterflies observed in each field. This number is called butterfly abundance.

Featured scientists: The Haddad Lab from Kellogg Biological Station Long Term Ecological Research Program – KBS LTER

Flesch–Kincaid Reading Grade Level = 7.3

10.24.24

A burning question

Fire crew in a woodland prescribed fire.

The activities are as follows:

Forests in the midwestern U.S. provide many important ecological services. They store carbon dioxide, which helps fight climate change. They also host a variety of plant and animal life. Forests provide spaces for recreation and support local economies through tourism.

Unfortunately, forests face threats. Climate change is causing more severe weather events, such as flooding and droughts. The spread of some parasites and diseases is also increasing as temperatures change. Forest managers are motivated to protect forest health. They can help combat these threats with their knowledge of different management practices.

Ellen and John have studied forest health in Wisconsin for decades. Ellen first became interested in nature while camping and hiking in Minnesota with her family when she was young. John became passionate about nature as a child while walking through the oak-hickory forests on his family farm. They teamed up with foresters from the Wisconsin Department of Natural Resources to examine the impact of prescribed fire as a management tool to increase forest health. A prescribed fire differs from a wildfire in that it is a planned fire that is set on purpose. When the conditions are right, forest managers will assign prescribed fires to specific areas to meet land management objectives. A lot of organization goes into prescribed fires to make sure the fire doesn’t spread or burn too hot.

Fire is part of the natural history of oak forests. They are adapted to recover quickly and they actually can benefit from fire. This is important for land managers who want to encourage the health of oak forests.

Ellen recording plant species diversity in a plot.

Oaks are considered a keystone species. This means they play a major role in maintaining ecosystem functions and the success of other species. There are two main reasons. First, they produce large amounts of acorns, which are food for many types of wildlife. Second, their canopies have more open spaces that allow light to reach the forest floor. Light is an important resource for plants, and smaller plants are limited by the shade of large trees. More light passing through the canopy allows more plants to grow below the oak trees. This increases the variety of species found in oak forests.

Ellen and John wanted to know if there were more plant species in oak forests that had prescribed fires. To answer their question, Ellen and John decided to study a part of the Madison School Forest in southwestern Wisconsin. This oak forest is special because research has been done on the impact of fire for over 75 years. In 1996, the forest was split into 15 units that have been under different management plans. One of the experimental treatments included prescribed fire at different frequencies. For example, the units in the prescribed fire treatment could have been burned every 1 to 4 years. Other units served as a control and were not burned. Comparing the control to plots that had been burned allows managers to see how often oak forests should be burned to increase forest health.

All of the management units were sampled in 1996 when the experiment first began and again in 2002 and 2007. In each sampling year, the number of plant species, or species richness, in the management units was counted. In 2023, Ellen, John, and their team resampled the plots to pick up this experiment where it was left off. This research will guide the best ways to support the health of oak forests and determine how important fire is to maintaining forest biodiversity. If fire is necessary to maintain oak forests, and oaks are a keystone species that support biodiversity, the research team expects to find higher biodiversity in plots where prescribed fire has been used.

Featured scientists: Ellen Damschen (she/her) and John Orrock (he/him) from
University of Wisconsin-Madison. Written by: Amy Workman (she/her)

Flesch–Kincaid Reading Grade Level = 8.8