If you drive down a country road in Southwest Louisiana, you might not even notice the prairies all around you. Unless you have studied the plants, animals, water, and soil of prairies, you probably would not think it is that interesting unless a showy wildflower is in bloom or flitting butterflies get your attention. If you grew up on the Cajun Prairie, you may even think those plants and insects are so common that they are just boring weeds that need mowing or annoying bugs that mess up your windshield. When our children whined that something was boring, my retort (which they now proudly refrain) is that everything is boring until you start to understand it. I hope this primer will help make the prairie look a little different to you on your next drive down a country road. 

An Overview

Biology textbooks about ecology introduce the biomes found on earth: terrestrial biomes like grasslands, tundra, deserts, tropical forests, and aquatic biomes like ocean, streams, rivers, lakes and wetlands. Prairies are grasslands. So are savannas of Africa, pampas of South America and steppes in Asia. Each has something distinguishing about them, but what grasslands have in common is that their primary vegetation is grasses, of course, with wildflowers (often called forbs) mixed in. Grasslands are relatively flat with few or no trees. How they got that way depends on their geological history. How they stay that way, in Louisiana anyway, depends on how humans have been managing them with fire and grazing for millenia. 

The entire middle third of the United States is grassland. Louisiana’s coastal prairies are distinct from the tallgrass, mixed grass and shortgrass prairies of America’s Great Plains because they are wet. We also have warmer temperatures, milder winters and longer summers (thus longer flowering windows¹). We have many more wildflowers and wildflower species in our prairies than prairies up north. Our prairie’s soil has a shallow clay pan that holds water but also makes it difficult for native trees to get established. Grasses are well adapted to this setup. Some species’ roots can penetrate up to twenty feet deep.  Grasses are so well adapted that little else can get a foothold in a virgin prairie. 

The base of every food web on earth consists of the organisms that can photosynthesize. All life in the ocean depends on algae and photosynthetic bacteria (phytoplankton), and all life on land depends on plants and a few algae. Biologists call photosynthetic life forms producers because they use the energy of the sun to convert small, inorganic carbon dioxide molecules in the air or dissolved in water to larger, energy-rich sugars.  This is why biologically productive land like prairies make excellent carbon sequestration factories that can lower carbon dioxide levels in the air and slow the rate our world is warming up.  

Producers use the sugars they make in two ways. They can burn them for energy (to make ATP by cellular respiration), or just as importantly, they use them as the starting material to make every protein, fat, starch and DNA molecule in every cell of their bodies, from leaf to flower to root to stem. The animals, bacteria and fungi that steal these large molecules made by plants and other producers are called consumers. Herbivores are consumers that eat living plant material like leaves, nectar and pollen. Carnivores are the animals that eat herbivores or other carnivores. Other consumers include parasites like fleas and mites that live off of other animals without killing them, and detritivores like buzzards and fly larvae (maggots) that consume animals after they’re dead.  Those categories have blurry and overlapping boundaries because most animal species are omnivorous. Fungi and bacteria are the cleanup crew that return many of these molecules to the soil once broken down for their use.

In a climax community of producers and consumers that have coexisted through evolutionary time, the producers produce enough plant material to compensate for predation. In many cases the plants and animals have struck deals, like pollination, soil improvement and seed dispersal that benefit both. So plants aren’t just being generous donating their hard-earned sugars and proteins. They just have evolved to make enough. 

The charismatic animal ambassadors of prairies are showy butterflies, native bees, fireflies, and charming birds. These are the examples we trot out for outreach to inspire the public to preserve and restore prairie. But the diversity goes far beyond these. The spiders, frogs, dragonflies and soil dwellers like worms and millipedes play outsized roles in prairie ecosystems. How many of these would you notice driving by on a country road? Maybe the occasional hawk, but anything smaller would remain invisible unless you pulled over, put on your boots, and took your time to stoop down and really look.

Unless you’re a biologist, you might be shocked at how much insect life is on your land. Most people only ever notice the mosquitoes, wasps, ants, and maybe dragonflies near their houses or pests in their vegetable gardens. Or maybe a cardinal or wren. It is important that you see the huge insect diversity under your nose for yourself, or else you might spend your life thinking the only good insect is a dead one. Why are invertebrate animals like insects, spiders, crustaceans and worms such a big deal? Because they are a huge food source for other wildlife in prairies and every ecosystem on land. If you go to chemical extremes to eliminate bugs that you consider pests, you’ll likely kill more of the invertebrates you never see, including those that were providing natural control of your pests, thus making your problem worse. Killing or repelling insects, even with “nontoxic” or “natural” chemicals disrupts balances and favors the bullies that bother us most. The alarming decline in insects, and therefore birds, in the past fifty years is due to dramatic habitat loss to agriculture, urban sprawl and landscape fragmentation that has reduced the sizes and connectedness of the few habitats we have left. That’s why I’m begging you to reconsider your respect for insects. I don’t love them all either, and I do manage hostile wasps and ants around our house. But I know the less weedy insects are vulnerable and declining and deserve my protection. 

Without plants, there will be no wildlife. Without a diverse suite of plants in your grassland, there will not be diverse wildlife. Without the right plants, there will not be the right wildlife. With only invasive plants, you may only get pest wildlife. Without a healthy community of plants and animals, you won’t get healthy soil, and waterways connected to your land become impaired by silting in, muddying, and therefore loss of the animal life that keeps the waterways clear and clean.

At the base of every terrestrial ecosystem are native plants.

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¹This long flowering window makes it more difficult for beauty to have impact in a snapshot. More northern latitudes have short flowering windows where all the species have to bloom, be pollinated, and set seed in a couple of months. This makes that flowering period an exuberant event in those latitudes, but nothing the rest of the year. And it’s why more of these prairie images make it onto jigsaw puzzles and screensavers.