 We're all familiar with grasses that form a sod, a thick mat of vegetation that is connected underground by roots and stems. However, in Wyoming and elsewhere in the West, many grass species do not form a sod. Instead, they grow in clumps, sometimes with lots of bare spaces between plants. So what's up with that? Isn't this bare ground a waste of productive space, a place where weeds and erosion can occur? Actually, bunch grasses make sense in places that don't get a lot of rain. Bunch grasses have extensive root systems that spread out into those seemingly bare spaces between plants. They very efficiently absorb any rain or snow that falls there and concentrate it into the vertical growth of the clump. Bunch grasses often produce as much or even more forage on the same site as the low-growing sod formers, and they hold the soil equally well. When you see bunch grasses growing on Wyoming range land, you're just seeing another adaptation to our dry climate. Bunch grasses are often a sign of health and productivity. I'm Gene Gade from the University of Wyoming Cooperative Extension Service.