Mycorrhizal Networks in Backyard Meadows

ISEF Category: Plant Sciences

Subcategory: Ecology  ·  Difficulty: Intermediate  ·  Setup: School Lab  ·  Time: 1 to 2 Months

The Hook

Plants do not always grow alone. In many meadows, roots trade nutrients and signals with fungi, almost like a hidden cable network under the soil. You can test whether that network changes when different plant neighbors grow nearby. That turns a backyard patch of grass into a real ecology project.

What Is It?

Mycorrhizae are fungi that connect to plant roots. The fungus gets sugars from the plant, and the plant often gets better access to water and minerals. Under the microscope, stained root pieces can reveal these fungal structures, including hyphae, which are the threadlike fungal filaments.

Think of a plant root like a charging port, and the fungus like an adapter that reaches farther into the soil than the root can. If two nearby plants support the same fungal partner, their roots may show different amounts of colonization. Your project asks whether the identity of the neighbor plant changes how often these fungal connections show up in roots from a meadow.

Why This Is a Good Topic

This is a strong science fair topic because you can observe a real ecological relationship and compare it across different neighbor plants. The idea is testable, because you can sample roots from defined spots, stain them, and score fungal presence with a microscope image. It connects to plant competition, nutrient sharing, and soil health, which matter in gardens, farms, and native habitats. You can also learn how to design controls, quantify microscopy images, and compare groups with statistics.

Research Questions

• How does neighbor plant identity affect the percentage of root length colonized by mycorrhizae in a backyard meadow?
• What is the effect of growing beside a grass versus a broadleaf neighbor on mycorrhizal staining intensity in roots?
• Does the distance from a target plant to its nearest neighbor change the amount of visible fungal colonization?
• To what extent does plant species diversity around a root sample predict the frequency of fungal structures in stained roots?
• Which meadow microhabitat, such as shade, edge, or open patch, shows the strongest link between neighbor identity and mycorrhizal presence?
• How does the abundance of mycorrhizal structures differ between native and nonnative neighbor plants in the same meadow?

Basic Materials

• Backyard meadow or schoolyard sampling area with permission to collect roots.
• Digging trowel or hand trowel.
• Clean paper bags or labeled zip bags for root samples.
• Nitrile gloves.
• Ruler or measuring tape.
• Smartphone with camera.
• Smartphone microscope adapter or clip-on macro lens.
• Slides and coverslips.
• Forceps.
• Droppers or pipettes.
• Clear storage cups or small beakers for rinsing.
• Trypan blue stain and the basic staining supplies your school lab allows.
• Distilled water.
• Dissecting needle or fine tweezers.
• Notebook or data sheet.
• Graph paper or spreadsheet template.

Advanced Materials

• Compound microscope with camera attachment.
• Root clearing reagents approved by your lab supervisor.
• Trypan blue stain prepared under school or university lab supervision.
• Microcentrifuge tubes or small specimen vials.
• Fine balance for sample mass tracking.
• Image calibration slide or stage micrometer.
• Digital calipers for root or plant spacing measurements.
• Soil pH meter or probe.
• Soil moisture meter.
• GPS or mapping app for plot layout.
• ImageJ for image scoring and area measurement.
• Statistical software for group comparisons and regression.

Software & Tools

• ImageJ: Measures stained root area, estimates colonization, and helps you score microscope images consistently.
• Google Sheets: Organizes sample metadata, neighbor identity, and summary statistics in one place.
• R: Runs group comparisons, regression models, and simple visualizations for your colonization data.
• QGIS: Maps sampling spots in the meadow and helps you compare spatial patterns.
• Python: Automates image sorting, file naming, and repeatable analysis steps if you have many samples.

Experiment Steps

1. Define the ecological question you can answer with real meadow samples, and pick one target plant plus a few clear neighbor categories.
2. Decide how you will sample roots so each plant group has the same basic structure, spacing, and habitat context.
3. Plan your staining and imaging workflow so every root sample gets scored with the same visual rules.
4. Build a scoring method before collecting data, such as percent colonized root length or a simple colonization index.
5. Choose controls that separate neighbor identity from other factors like shade, soil moisture, and patch location.
6. Plan the statistics you will use to compare groups and check whether the pattern still holds after you control for confounders.

Common Pitfalls

• Sampling roots from mixed patches, which makes it impossible to know which neighbor plant you are actually testing.
• Overstaining or underclearing roots, which hides fungal structures or makes them look like debris.
• Using different lighting or magnification for different slides, which changes how colonization looks in photos.
• Treating every root piece as independent when many pieces came from the same plant, which inflates your sample size.
• Ignoring soil moisture, shade, or patch edge effects, which can make habitat differences look like neighbor effects.

What Makes This Competitive

A strong version of this project goes beyond, “Do I see fungi or not?” You would quantify colonization in a repeatable way, compare several neighbor identities, and test whether the effect still appears after you account for patch conditions. Extra strength comes from a careful map of sample locations, clear image scoring rules, and a statistical model that handles nested data from the same plants or plots. That kind of design shows real ecological thinking, not just good microscopy.

Project Variations

• Compare mycorrhizal colonization in native versus invasive neighbor plants in the same meadow.
• Test whether edge plants and interior plants differ in fungal staining patterns when the target species stays the same.
• Compare smartphone microscope scoring with compound microscope scoring to see how much agreement you get on the same stained roots.

Learn More

• USDA NRCS soil health resources: Explains fungi, roots, and soil biology, and you can find it by searching the USDA soil health site.
• NIH PubMed: Search review articles on mycorrhizae, root colonization, and plant neighborhood effects.
• NOAA educational resources: Use background material on ecosystems and habitat variation, found through the NOAA education site.
• NASA Earth Science: Find plain-language articles on plant communities, land cover, and environmental context.
• Mycorrhizal Symbiosis: A standard textbook for background on how fungi and plants interact, usually available through school or public libraries.