Lawns: A sure way to kill the planet

Dreaming with a big car and a new house with a perfect lawn on front, while wishing to keep a healthy planet is a very common, although inconsistent, American dream.

The fact is, lawns are planet killers, specially in the Bay Area or any other place where lawn grass is not native and requires so much water.

Let’s start with the irrigation. According to the Mountain View Environmental Sustainability Task Force, in 2008 60% of tap water spent in such city was used in irrigation. A similar percentage can be expected for San Jose. That gives an idea of how much water is wasted irrigating lawns. At a time where states and cities are thinking how to cut expenses, wasting water does not seem to be a very smart idea.

The perfect lawn has to be green and lush. Much of that is produced thanks to the addition of nitrogen, in form of nitrates, to lawns. This fertilizers are manufactured in a process that involves the burning of natural gas, generating big quantities of global warming gases. Nitrates can, once released in nature, become nitrites, a carcinogenic chemical. They are also washed easily from the soil and finish in streams or in underground water. When in streams or in the sea, they facilitate the grow of algae. These algae consume all the oxygen in the water, and create “dead zones” where there are no fish or animals. The dead zone in the gulf of Mexico created by the run-off of fertilizers from the Mississippi river is a good example.

To get rid of that slug, snail, spider or insect (probably innocuous) that we have been brain-washed to hate, a pesticide has to be use. Pesticides are toxic chemicals that stay in the ground for a while (for instance, a field is considered organic if it stayed free of pesticides for five years). They can be toxic to pets and human beings. Insects are part of the ecosystems: spiders kill and eat other insects (same as many wasps), ants and worms aereate the soil, bees and bumble-bees pollinate plants and trees and ladybugs are avid consumers of aphids and other common garden annoyances.

That green lawn, even when full of pesticides, is still a comfortable house for other wild plants. Since we have been educated to hate everything in the wild, we call them despectively: weeds. To get rid of weeds another poison, a herbicide, has to be used. Many of the plants that herbicides kill produce flowers that are visited by bees and other insects, or small fruits and seeds consumed by birds. Some weeds are actually edible plants that were (or are) consumed by humans in other periods and cultures: dandelion, chickweed, and mallows are an example, or that have medicinal properties. In any case, the combination of herbicides and pesticides makes sure that a halo of death surrounds the green lawn.

In a natural environment, grass grows, together with many other plants, in places where herbivores are around. These herbivores (cows, geese, deer, buffaloes) continuously “mow” the grass. In our artificial lawns, we need to use a gas or electric mower for that. The whole process is an amazing example of resource waste. We spend money and resources to grow a lawn, and then we have to spend more money and resources to periodically get rid of it.

Finally, we dispose all the cut grass and let the city take care of the rest. This is the last step in the circle of wasting. In some fortunate cases it will be composted and, at least, reused for something else, but in many cases it just goes to a land-fill, decomposing there little by little, usually in an anaerobic process that will generate methane, another greenhouse gas.

The dream of a lawn does not happen without casualties. Think it twice before taking care of yours or putting one. Let nature grow wild in your front yard, or at least put native, drought tolerant plants.

Published in "Alianza News"