The Science of Grass!
Lawns get walked and played on, dumped on (dogs) and abused in so many different ways yet they’re responsible for erosion control, cleaning water, cooling air temperatures, are aesthetically pleasing and they feel so good under your feet.
Now that school is in full swing science projects will be needed to be done as part of the statewide curriculum. In fact, many schools have science fairs to show off a student’s work. Back in my day, the norm was to walk in with a volcano (that the parent usually built) or a glass filled with dry ice to show what happens when water hits it. Wait! Are you saying you did this in your day, too? With ‘going green’ such a huge concern let’s focus on doing something with our crumb crushers that they’ll keep with them their whole lives – The Science of Grass!
Depending on the student’s grade level and age will depend on how long a science project will take to get results. The information we offer here is contingent on you how nice you’d like to make it. What do you say we get our green geek on?
Experiment: Sun, Half-Sun & Shade.
Sod is grown in soil but since our experiments will most likely be taken to school we aren’t going to plant it in the ground, but instead, make it mobile.
Start with a piece of Original Marathon Sod and cut it in three equal parts. To make your presentation stand out you may want to build a four-sided box with a bottom to put the sod in. Or, nurseries have square plastic flats that they might give to you. In a pinch, you don’t need to corral the grass and just let it be. Personally, when you are ready to take it to school I’d go to the dollar store and get a shadow box (which is basically a deep picture frame) and transfer the sod into it. Presentation counts!
Place one of the pieces in full sun, one that either gets morning or afternoon sun and the other in complete shade. Keep the grass of each one equally moist then take notes as to what happens to the sod after one, two, three and four weeks. Take pictures as you go along. At the end of the experiment note the findings.
Experiment: Root Growth.
Roots are essential for soil but the soil must have enough pour space between each particle for the roots to grow through. At the same time the soil must have properties that can hold moisture and wick it away when needed. When combined strategically sand, silt, clay and organic matter are the essential ingredients that form the best soil mix.
- One gallon black nursery pots
- One piece Original Marathon Sod
- Knife (to cut the sod)
- 5-gallon bucket full of water
- Soil samples to fill each nursery pot one inch from the top of the container. Each sample must look and be different. You can get it from your yard, an open field or bagged soil from a nursery). The more samples the better the experiment will be. At the very least use one with sand, clay and potting or garden soil.
Experiment directions: Before filling a pot with dirt invert a nursery pot over the sod and cut out a circle which will be used to plant once you have your soil in the container. As your filling the pot pack it down real good but only fill it up one inch below the top of the container. Don’t forget to mark each container with the type of soil it’s growing in. Now, put the sod in (green side up) and make good soil contact. Put each container in full sun and water, possibly daily, because pots will dry out faster. You want the soil moist but not wet. At the end of 6 weeks carefully pull the sod out of each container and knock all the dirt off the roots. Dunk the roots in water to give a good washing then measure the length to determine which type of soil roots grow through best.
For bonus points mount each one on a board. At the bottom of the root put a sample of the type of soil it was grown in. Make certain everything is labelled.
Experiment: Water (H2O).
Chances are you’ve been conditioned into believing that bottled water is better than tap water. We’re not here to debate that but what we want to learn is how grass reacts with different types of water.
- One piece Original Marathon Sod cut into equal thirds
- 5 gallons of tap water
- 5 gallons of purified bottled water
- 5 gallons microwaved tap water (boiled then cooled)
Either build a four-sided box with a bottom to put the sod in, fit grass in a square nursery flat or just place it on the ground in full sun two inches from each other. Before going any further measure how tall the grass is from the top of the soil to the top of the leaf blade and the intensity of its colour and write it in a notebook. Each grass sample will be watered with its own water (tap, purified and microwaved). Don’t get them confused. Water one with only water out of the hose, the other with purified water and lastly boiled water from the microwave – allow it to cool then water. This experiment can take between 4-6 weeks to discover which one works best.
Experiment: Grass Seed Germination.
This is a dual type of experiment. Here we measure how long it takes for grass seed to germinate and on what kind of soil. The fun of this experiment is we can use all kind of different things to grow the seed on.
- Plastic cups (punch a few small drainage holes in the bottom.
- Canister of Original Marathon Seed
- Medium (soil, vermiculite, sand, perlite, rocks, compost, carpet, concrete brick, etc.)
Fill the plastic cup to ½” from the top with any kind of medium as noted in the materials. I personally would use 2-cups with soil, 1 with pebbles, 1 with sand, 1-concrete block and 1 piece of small carpet (don’t cut it out of the living room). For the cups with soil I’d sprinkle seed on top and cover it with some soil. For all the others just sprinkle the seed on top and keep moist. Be careful with watering. Use a hand pump sprayer daily and note the progress to see which one germinates first and what happens after a few weeks.
All of these experiments are fun, easy and quite enlightening. The results you get will astonish the young and young at heart. You’ll definitely find an appreciation for the Science of Grass.
Nick Federoff, Horticulturalist
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