In his incomparable book The Omnivore's Dilemma, Michael Pollan describes Americans, quite justifiably, as creatures of corn. This is because of the ubiquitous nature of the plant - feeding us directly, feeding cows (who would be a lot happier eating regular grass), being turned into high fructose corn syrup to sweeten our food the cheapest way possible, being converted into countless food additives....corn is indeed king of our landscape.

Unless you are in the suburbs of course. There, anyone can observe that another grass has domesticated Homo sapiens - the common or garden lawn grass. We are its creatures, manicuring it, feeding it, ensuring no other plant crowds it  to mar its perfect greenness, and poisoning any insect that dares crop it. Even if we might admire a natural, wooded landscape on an opposing hillside, we prefer our own yard to be a pristine green sward. In fact, together with a deck and grill, owning such a lawn is the dream of most Americans.

So what?

Well, ironically, many of us homeowners will also be concerned about eating organically. There is - as in so many aspects of our lives - a disconnect between an understandable longing to avoid suspect chemicals in our food, and the desire to keep the lawn perfect, whatever the chemical ‘cost'.  It is, unfortunately, the case that the herbicides and pesticides that lawn companies use will also have an affect on the wider world - whether it be depleting the food sources of the springtime robins and autumn finches, or trickling into watercourses and our ground water to surprise us with accumulating toxicity.

Also, the other maintenance of the lawn has a very heavy toll on the environment

And then there is the rest of your yard - those trees and bushes, annuals........is this the best use of your time, money? Can you design something that works better for you and the environment?

Unfortunately, it is easy to be daunted by a lot of the advice that ‘green' web sites and books give you concerning wildlife-friendly gardening. What can we practicably do to have less of a negative footprint? Or better still, what ways can we actually enhance the area, rather than just do less damage?

We looked at the lawn recently in my earlier blog, Grass is bad for you. But here, my friends, is a recap.

LAWN MOWERS

According to the Environmental Protection agency, fifty-four million Americans use gas powered mowers; these, with other gas powered garden equipment, create five per cent of summer's US air pollution. 

My home is surrounded with a glorious two-thirds of an acre of lawn. Seeking to be more aware of what my Craftsman tractor mower was doing to the air, I used an on-line calculator to estimate that the twenty-horsepower ride-on tractor, which is eight years old, will produce in the 75 minutes it takes to cut the lawn.........7.5 kilograms (16.5 pounds) of carbon monoxide, 11.5 kilos (25 pounds) of carbon dioxide; and three hundred grams of nitrogen oxides (NOx) and particulates. The carbon monoxide eventually turns into the infamous greenhouse gas carbon dioxide, and the NOx and particulates are not only directly bad for human health, they also help generate ground-level ozone, which exacerbates asthma. 

To compare the inefficiency of this type of engine - which does not have a catalytic converter - I compared what my twelve-year-old Subaru would spew out of its exhaust pipe, covering sixty miles in about the same time. The answer?  Three times the CO2 and 37 times less CO (because it burns the fuel it uses more completely)...and one-fifth as much of the NOx and particulates. 

Hey, I'm good at math - and a whizz at chemistry - so I worked out that the carbon monoxide created by the lawn mower will turn into around twelve kilos of carbon dioxide. So, the car ride produces about 50% more CO2 (but hey - at least you've got some place in your car!) but the mower - five times the noxious NOx.

But what can you do to make this better? Well, here are some pretty simple, but effective ideas...

Cut the lawn at a higher cut - and after the heat of the day (as sunlight exacerbates the polluting effects)

Keep the mower well-serviced and the blades sharp

Try a push mower or electric mower if your lawn is small enough. Admittedly, using an electric mower is pushing the pollution back a step, but at least there is a chance that your electricity comes from a cleaner source than the primitive gasoline mower engine.

The best idea, however, is to reduce the size of your lawn.

REDUCING LAWN SPACE

Most of our problems are linked to the thirst for bigger homes and larger yards. We buy properties with lawns that only a decathlon contender could keep cut using a push-mower....so we are forced to use gasoline-driven machines that spew out spectacular amounts of pollution.

And only someone with a hermit's patience could excise 12,000 dandelions from the same lawn....so we are forced to use herbicides.

So, in the long term, reducing the lawn area is the best, almost the only option to have a reduced negative and more of a positive.

A reduced negative - less water used, less pollution from mowers, fewer chemicals used to kill crabgrass, clover and dandelions.

• A big positive - because you can grow plants that will attract birds, butterflies and bees....and which look beautiful too.

So, next time, I will look at this in more detail. Why didn't we have the balance between lawn and plants better in the first place?

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