Green Grass Without Synthetics

There are benefits to having grass in parks and residential properties. When taken care of, grass becomes a natural carpet on which one can easily rest, play or walk. But to keep Poa pratensis green and thus in a juvenile state requires an investment of energy, an amount that is exaggerated by our questionable habits.

The typical high maintenance option involves buying synthetic fertilizer for spring and autumn applications, herbicide for weeds and pesticides for grubs. Some hire a company to drive around the neighbourhood to periodically spray lawns with the necessary concoction. To avoid the nuisance of a long electrical wire, people buy  gas-powered mowers.  And to prevent leaves and tree seeds from accumulating on lawn, blowers come to the rescue.

Even if people with such habits are aware that making fertilizer is an expensive  process partly because nitrogen does not spontaneously react with molecular hydrogen; even if they know that some fertilizer-pellets inevitably get sprayed onto sidewalks where they damage concrete, induce diarrhea in dogs and end up in storm drains and eventually into waterways and contribute to eutrophication; even if they suspect that the use of pesticides has ecological consequences;  even if they are aware of  the carbon footprint of synthetics and mowers and of the noise pollution of blowers, there is a possibility that they persist with their habits because they believe there is no alternative.

But when there is a will to change, there are always other options. One reason people turn to mass-maintenance techniques is that they plant more grass they can handle. City parks or residents can instead plant more trees, shrubs and cultivate gardens, which is what we did with 2/3 of the lawn we originally had in our backyard. I never spray any of our fruit trees or apply any pesticides to our garden. Instead of synthetic fertilizer, we rely on  a combination of household compost and composted chicken manure.  Grass cannot be eaten, but from July to October we have not needed to buy any tomatoes, garlic, parsley, basil, thyme or Swiss chard. We still have frozen cherries from our tree and we’ve also enjoyed arugula, fresh beans, onions and Mexican peppers, most of which were grown from seed.

P1150783.JPGA city bylaw prevents us from cultivating the front yard, but I manage to sneak in some oregano and bird’s-foot trefoil. They require less water and nitrogen than Kentucky bluegrass and displace  weeds. Since our city does not use pesticides on the grass between our sidewalk and road, dandelions, crabgrass and plantains find their way into our property. But I just pull them out with a hand tool. As an alternative to synthetic fertilizer, mulch from the electric mower is left on the lawn so that essential elements like nitrogen, phosphorus and potassium can be recycled. To supplement the lawn with more natural fertilizer, we let the dog pee on it and then immediately add collected rainwater to prevent “burning”. Due to their carnivorous diets, dogs’ urea is highly concentrated so it easily creates a hypertonic solution that needs to be diluted. In the spring the melting ice and snow takes care of that. Spots that don’t receive their share of dog pee get coffee grounds, which also keep the lawn green.

Abating the effects global warming involves more than reducing the use of fossil fuels for transportation and electricity-generation. They only account for a combined 45% of greenhouse gases(see pie chart below). Just about everything else ranging from reproduction to growing grass and food also impacts climate change. To solve the problem, regardless of the field of human activity, green or technical, we have to conserve and act more benignly towards ourselves and our surroundings.

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AFOLU is an acronym for agriculture, forestry(deforestation) and other land uses. Its large contribution to greenhouse gases is often ignored in media reports about climate change. Source: www.ipcc.ch/report/ar5/wg3/
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From Playing Cards to Clover

If we keep looking at the same thing over a period of time with an uncritical, non-curious or distracted mind, attenuation sets in. And not only do our nervous systems tune out what’s commonplace, we also develop a false sense of history. We act as if things always were as they currently appear to be, and as if they will continue to be immune from flux.

Take playing cards as an example. If one was raised in North America and was not in contact with recent Spanish, Moroccan or Italian immigrants, it’s likely that the person has a fixed image of playing cards: 52 cards, 13 in each of four suits: clubs (clover), hearts, spades and diamonds with three of the cards being a king, queen and a jack.

Cards
The four suits of Neapolitan playing cards like those of other Spanish and Italian cards differ from French ones.  The former’s suits are far more similar to those of the first cards imported into Europe from Egypt in the 14th century. Pic by the author.

But these familiar cards are just one version, one that originated under the rule of  King Charles VI of France between 1380 and 1422. They continued to evolve a little later in the 15th century into their current forms which are neither unique nor static.  Take a tour of  cafes in Italy and you will see people playing with variations upon the theme of Italian-Spanish cards:  the king is still present, but there is a cavalier and a servant instead of the queen and jack, respectively. And there are only 40 cards with suits of clubs (large sticks), cups, swords and coins. These strike more of a resemblance to the first cards that were imported into Europe by Italian merchants around 1360. They discovered them while trading with Mamluks in Egypt. The cards had the same suits like those of contemporary Spanish and Italian cards, except that they featured a wand instead of a club.  Regional cards in Northeastern Italy still include a wand as a suit.

I often wondered why the word “club” is used for the clover leaf, one of the four suits of French cards. One hypothesis is that the suit was associated with commoners who grew clover alternately with their crops for fodder and in order to enrich the soil. But wooden clubs were also commoners’ weapon of choice, so the name “clubs” stuck to clover.

Clover is a legume whose roots include a mutualistic relationship between bacteria and plant cells.

cloverroots
The arrows point to white clover’s root- nodules, the site of nitrogen fixation by mutualistic bacteria. (The scale is in inches. 1 inch = 2.54 cm) Picture from NC State Extension Publications – NC State University

Thanks to bacterial enzymatic action, valuable nitrogen compounds are made from otherwise unusable nitrogen air molecules. In exchange, the bacteria receive shelter and sugars. Before many people developed the bad habit of adding herbicide to lawn grass, white clover seed  was often mixed with grass seed. Clover, when coexistent, helps grass by adding nitrogen compounds to the soil.

Like playing cards, not all clovers are alike. White clover is adapted to moist conditions. It should not be the only companion of lawn grass. Especially where grass grows on slopes where water drains easily, it makes more sense to grow bird’s foot trefoil. Scientifically known as Lotus corniculatus , it is another leguminous plant which does better in arid conditions and which will help abate dandelions. These unpopular relatives of the lettuce in turn out-compete grass when less water is available. A smaller legume with smaller yellow flowers, black medic, can do well in both moist and more arid soils. And of course there is a common origin to the genera of the bird’s foot (Lotus), to medic (Medicago) and to that of at least 238 Trifolium species, including red and white clover—-we see it in the similarity of leaflet shape, small pea-like flowers and to the all-important and welcome infection in their productive roots.

clover
Clover and clover-like plants belonging to 3 different genera of the legume family: from left to right, Trifolium repens (white clover), Lotus corniculatus (bird foot’s trefoil) and Medicago lupulina (black medic). Just about all Trifolium species are bee-pollinated. All pics from wikipedia commons.

Their family Leguminosae evolved about 56 million years ago, 9 million years after large dinosaurs went extinct. A few million years later, their most important clades separated. From genetic analyses, it’s been determined that their evolution occurred quickly, reminiscent of  the way playing cards quickly branched out in Europe. And like the latter,  the 18000 species of legumes are now spread all over the planet. They are being used for food, oil, lumber, fiber, medicines, aesthetic purposes and not least of all, for a vital role in the Earth’s nitrogen cycle.

SOURCES:

Lavin, et al. 2004. Evolutionary Rates Analysis of Leguminosae Implicates a Rapid Diversification of Lineages during the Tertiary. Systematic Biology 54 (4): 530-549 http://sysbio.oxfordjournals.org/content/54/4/575.full

The Botanical Garden. Phillips and Rix

The Mediterranean and Mediterranean World. Francois Braudel

The four suits of a pack of cards www.theguardian.com/books/booksblog/2013/dec/04/books-advent-calendar-4-four-card-suits

Have you ever wondered why the symbols on playing cards are called…. http://www.brierfieldbridgeclub.org.uk/themes/Have%20you%20ever%20wondered.htm

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