Do Clover Lawns Boost Plant Richness?

ISEF Category: Plant Sciences

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

The Hook

A lawn can look green and still be almost empty of plant life. Add clover, and you may give more species a place to grow. That makes your yard a living test plot. You can measure that change with quadrats, photos, and seasonal surveys.

What Is It?

This project asks whether lawns with more clover support more kinds of plants than standard turf lawns. Plant species richness means the number of different plant species you find in one area. Think of it like counting the different apps on two phones, not just how full the screen looks.

Clover-rich lawns often have a more mixed plant cover than a monoculture turf lawn, which is a lawn dominated by one grass species. More open space, more flowers, and different mowing patterns can change which plants survive. You are not just asking whether the lawn looks nicer. You are asking whether the plant community is more diverse.

You can measure that diversity with quadrats, which are small square sample areas placed in the lawn. iNaturalist can help you identify unknown plants from photos, and seasonal repeats let you see whether richness changes across the year.

Why This Is a Good Topic

This topic works well because you can measure it in real yards with simple tools, but it still asks a real ecology question. You are testing how lawn management and plant choice shape local biodiversity. That connects to pollinator habitat, urban ecology, and water-wise landscaping. You can also learn field sampling, species identification, data tables, and basic statistics without needing a lab.

Research Questions

• How does clover cover affect plant species richness in residential lawns across a season?
• What is the effect of mowing frequency on plant species richness in clover-rich lawns?
• Does lawn size change the relationship between clover cover and species richness?
• To what extent does flower abundance predict plant species richness in mixed lawns?
• Which lawn type, clover-rich or monoculture turf, supports more non-grass plant species per quadrat?
• How does species richness change from early season to late season in clover-rich lawns?
• What is the effect of sunlight exposure on plant species richness in residential lawns?

Basic Materials

• 1 m x 1 m quadrat frame or string square.
• Smartphone with camera and iNaturalist app.
• Clipboard and field notebook.
• Printed lawn map or site log sheet.
• Measuring tape.
• Masking tape or flag markers.
• Digital kitchen scale for optional biomass checks.
• Plant identification field guide for local common lawn species.
• Weather app or local climate records.
• Spreadsheet software for data entry.

Advanced Materials

• GPS-enabled smartphone or handheld GPS unit.
• Digital camera with fixed settings for photo plots.
• Portable soil moisture meter.
• Light meter or PAR sensor.
• Soil pH meter or access to soil test kit.
• R or Python for ecological statistics.
• ImageJ for photo-based cover estimates.
• GIS software or Google Earth for site mapping.
• Reference herbarium keys for regional plant identification.
• Binocular loupe or hand lens.

Software & Tools

• iNaturalist: Identifies plants from photos and helps confirm species records from your quadrats.
• ImageJ: Estimates percent cover from plot photos and compares lawn structure across sites.
• Google Sheets: Organizes quadrat data, richness counts, and site variables in one place.
• R: Runs species richness comparisons and basic ecological tests like t-tests or ANOVA.
• QGIS: Maps lawn sites and helps you compare spatial patterns across neighborhoods.

Experiment Steps

1. Define your sampling unit and decide how many lawns and quadrats you will compare.
2. Choose the lawn traits you will measure, such as clover cover, mowing pattern, sunlight, and species richness.
3. Set up a repeatable photo and identification workflow so every quadrat gets scored the same way.
4. Build a data table that separates observed species, uncertain IDs, and repeated sightings across the season.
5. Plan controls that account for yard-to-yard differences, such as shade, irrigation, and lawn size.
6. Decide which statistics will test your main question, then sketch how you will compare groups over time.

Common Pitfalls

• Counting the same patch of clover as multiple species because the leaves vary in shape.
• Using iNaturalist photos without checking whether the plant is actually visible enough for a reliable ID.
• Sampling only the prettiest lawns, which biases richness upward and weakens your comparison.
• Measuring lawns at different points in the season without keeping the timing consistent across sites.
• Ignoring shade, irrigation, or mowing differences, which can explain the richness pattern instead of clover cover.

What Makes This Competitive

A stronger project will compare more than two lawn types and control for the big yard variables that affect plant growth. You can raise the level by using repeated seasonal sampling, blind photo scoring, and statistics that test whether clover still matters after other factors are included. If you map sites and connect richness to management history, your project starts to look like real urban ecology. Clear methods and clean data matter more than a huge number of lawns.

Project Variations

• Compare clover-rich front lawns with clover-rich backyard lawns to test whether mowing and foot traffic change richness.
• Swap species richness for native plant presence to see whether clover lawns help local wildflowers and not just common weeds.
• Use percent cover from photos instead of simple counts to test whether mixed lawns have more even plant communities.

Learn More

• USGS Native Bee resources: Search for plant and pollinator habitat guides that explain why mixed lawns can support more biodiversity.
• NIH PubMed: Search for review articles on urban lawn biodiversity, clover lawns, and plant community ecology.
• NOAA Climate Data Online: Find local weather records to compare rainfall and temperature with your seasonal lawn surveys.
• iNaturalist Help Center: Learn how to make reliable observations and improve plant identification from field photos.
• MIT OpenCourseWare Ecology courses: Find free lecture notes on sampling, species richness, and community ecology.