Let’s start with an exercise.
Hold out your thumb and observe how large it is.
It’s likely no taller than two nickels stacked on top of each other with the thickness of a couple of pencils. The variation of size might vary from person to person, but the general sentiment remains the same.
Hold up your thumb in the room you’re in. How much space does it take up now?
Step outside to your patio or your yard, and repeat the exercise. The ratio has gotten increasingly smaller.
Keep that perspective in your mind because that thumb — that imminently crucial yet disproportionately small portion of your body — is roughly the same size as a cultivar of grass. This might not mean a lot at first, but hold that image for a bit and you start to understand how much influence these tiny tangles of blades and roots possess.