Biodiversity is the variety and spice of life; it is also its bank account and health insurance. It is a measure of how many different interacting species are in an ecosystem. Generally speaking, the more the better. Systems with high biodiversity are more able to withstand outside invaders and environmental insults like drought, flood, and pollution. It is not just rare species that are valuable, every living thing in an ecosystem counts.
Ecological landscapers use the concept of diverse, healthy ecosystems adapted to local climate and soil to manage properties as a whole, giving us the most stable, attractive and useful landscapes with the least amount of maintenance effort, cost, water use and material input. This is an incredibly powerful concept. It differs significantly from the way most suburban landscapes are currently managed, where the focus is on large inputs of fertilizer, pesticide and water to grow a single species (turfgrass), and on continually treating the same individual pests and diseases year after year.
When we cultivate a healthy, biodiverse ecosystem suited to our own town's local soil and climate, the depth and breadth of services our yard can provide us are truly astonishing. The physical processes alone are invaluable, including carbon sequestration, aquifer replenishment, water purifying, air purifying, nutrient recycling, composting, soil building, and residential home cooling in summer. Even our neighbors and town can benefit from our yard, through cleaner air and water. The value of these services alone far out-weighs the cost a taxpayer would have to fork out for a town’s DPW to do the same. Just ask NYC, who found it cost effective to protect natural land in their watershed rather than build expensive water filtration infrastructure. How about keeping pets? Our little biological friends we enjoy so much, the birds, butterflies, dragonflies, rabbits, chipmunks, squirrels, bats and pollinator species, now live happily in the shelter that our plants have created, eating the food our ecosystem is generating, managing our pest insects, and being cleaned up after by our tiny composting organisms. All this enjoyment you get for free, compared to the upwards of $3,000 annual cost of owning a dog.
Most importantly perhaps, we ourselves now have an outdoor sanctuary where we can rest, relax, play and experience nature. The Japanese have a word for this, shinrin-yoku, the simple practice of enhancing health by going outside to visualize, touch, listen to, and quite literally inhale nature. It means essentially to bathe in biodiversity. Studies show this to be good for our health in ways we don’t even understand yet. In fact, our yard full of green plants, trees, and grass can help reduce not only our, but our neighbors’ mortality from cancer. A recent national study found that women whose lives are surrounded by greenness from plants, within 250 m of a home, have a 12% reduction in cancer mortality compared to those who live surrounded by man-made structures.
There’s more. Did you know that you are an ecosystem yourself? Your gut is inhabited by hundreds of species of bacteria, your skin by thousands of species. These bacteria are most often in a highly beneficial mutual relationship with us, or are at least living a non-harmful coexistence. Science is just beginning to understand how these microbiota influence our health. As Michael Pollan put it, “the implications of what has already been learned, for our sense of self, for our definition of health and for our attitude toward bacteria in general — are difficult to overstate. Human health should now be thought of… as a function of the community, not the individual.”
This might be hard to take in, but, you are a part of your yard’s ecosystem, and it is part of yours. The microbial life in your soil is related to the microbial life on your skin, the same for your gut. Remarkably, this is an exceptionally good thing; this is how humans evolved to live so successfully in this complex ecosystem we call the world. These tiny cells help protect us from infections, digest our food, influence our appetites and help our immune systems. In fact, new studies have linked higher environmental biodiversity in the surroundings of people’s homes to fewer skin allergies. Your beautiful, biodiverse yard really can make you and your family healthier.
On the dark side, because there always is a dark side, since we are all connected to your yard, it means that the chemicals and synthetic fertilizers you put on your lawn are also in your body, in your family, in your neighbors, and in the town’s air and water. These chemicals don’t just affect the grubs, or the dandelions, or the crab grass, they affect every single one of the trillion organisms that make up your yard’s ecosystem, including you. In humans, these chemicals are carcinogens (EPA lists 70 carcinogenic pesticides, including herbicides, fungicides, pre-emergents and insecticides available to purchase in the U.S.), and reproductive, neural, and developmental toxins. In your yard’s ecosystem, they are a disaster, decimating the microbial, fungal and beneficial insect populations, killing all plants except grass, and disrupting normal soil processes that support plant health. This lifeless yard now needs constant inputs of fertilizers and water in order to support the single species you have left, turfgrass. Instead of having a yard that supports your health and sense of well-being you now have a yard that increases your risk of chronic disease.
And of course, each yard makes a difference to the planet. In the U.S. alone, lawns make up 49,000 sq mi, making it the nation's largest irrigated crop. What we do with our own yards matters a lot. By creating a biodiverse property, or simply helping it to create itself, your ecologically managed yard will make us all healthier. Experience your own shinrin-yoku - step outside onto your lush, green, organic lawn; see the monarch butterfly alight on your milkweed; hear the sparrows chirping in their nest; take a breath of pure, fresh air; feel the sun, feel the connection; and savor a deep sense of satisfaction about your thoughtful care of this small piece of the world under your feet.
Checklist for an eco-friendly property
Use non-synthetic fertilizers from natural sources. Synthetic fertilizers are made in a chemical process that uses fossil fuel and contributes to global warming. Use of synthetic nitrogen fertilizer greatly increase the amount of nitrogen entering the global nitrogen cycle which has a serious negative impact on the organization and functioning of the world’s ecosystems, including accelerating the loss of biological diversity and decline of coastal marine ecosystems and fisheries. The use of synthetic phosphorus fertilizers has its own set of problems, in particular its contribution to the growth of pondweeds in fresh water lakes and ponds, and the limited global supply of phosphate rock.
Reduce water use. In many cities in the Northeast, 50% of the drinking water goes to lawns and landscapes. Over 75% of Massachusetts’ rivers are flow stressed during the summer because of water withdrawals for these residential uses.
Increase biodiversity. Biodiversity is the key to a healthy ecosystem on any scale, from backyard to global. Biodiversity increases the stability of ecosystems, reduces the need for intervention, and makes them, from an aesthetic viewpoint, much more interesting. The earth is currently losing species at a rate that rivals mass extinctions in our geologic record.
Care properly for your lawn... Mow high, 3”-4”; leave grass clippings on lawn; water infrequently, if at all; encourage a bit of white clover; fertilize lightly with compost; and seed bares spots in fall and early spring. Rake your lawn, but not your woods: let leaves, nature’s own mulch, stay and compost in place.
Grow food. Organically raised fruits and vegetables, grown close to home, will become more valuable as current trends in climate change, energy cost and availability and human health play out in the future. Organic practices allow edible and decorative plants to be grown together. There are many ways to incorporate food plants and vegetable gardens into your landscape. Blueberry bushes are native, decorative and delicious. Many fancy lettuces are as pretty as annuals.
Make and use compost. Compost has many advantages as a soil amendment and it is less likely to cause pollution of the local and regional environment than fertilizers, even organic ones. Incorporating compost improves turf, shrub and shade tree performance in marginal or poor soils. Good quality compost improves soil structure, reduces runoff and compaction, enhances biodiversity, increases water and nutrient retention, increases microbial activity, supplies nutrients, helps suppress and prevent plant diseases, detoxifies certain pesticides, and inactivates and kills potential human pathogens.
Remove invasive plants. Invasive plants grow quickly and spread easily and often reduce the biodiversity of whole ecosystems. Learn about invasive plants, how to avoid spreading them, and how to remove them from your own property.
Garden with native plants. Native plants are site adapted and usually require little to no watering, fertilizing or pesticides. Stunning gardens can be made from entirely native plants. Since native plants are, well, native, it’s best to find a local conservation group who works with natives.
Test your soil. If you want your property to look its best, to save money, and to protect the environment even more, do an easy soil test before you apply anything at all. A soil-testing lab will help you figure out how much of which fertilizers and nutrients to apply for optimum results.