I have not read the article, Heather, David and Reid, but I think the basic point is good one — maintenance should be consideration in designing a “sustainable residential landscape.” Even here in the SW, we will design what we think is a more sustainable landscape, and put in a water harvesting swale with cobbles. As it turns out the maintenance costs for that particular strategy in terms of energy (to remove organic debris that collects in them periodically), pesticides (for the weeds) and even $ to our clients make it less sustainable. Plus nobody really factors into the equation the environmental cost of mining the cobbles.
As for the lawn debate, David, not all “green space” is equal from a carbon sequestration perspective. Hardwood trees for example are a much better choice if that is your goal. I am sure you also are aware of the huge environmental cost that goes well beyond the maintenance cost. There are huge dead zones now in the Chesapeake Bay are and down in the Gulf of Mexico that have evolved over the last 30-40 years that are at least in part the result of the nitrates and phosphates in urban runoff from suburban lawns and their maintenance requirements. A study conducted by some of the scientists involved in the Baltimore Eco-system Study showed that greatest change in land use and land cover over that same time period in many of the sub-watersheds of the Chesapeake, was an increase in turf/lawn area (and believe it or not, forest) but not agriculture. So, the conclusion was the increase in suburbanization was the most likely explanation for the increase in nutrients and pesticides that had found there way into the Bay. I do not have a citation, but could try to find if you like.
But in the end, carbon sequestration may not be the most important sustainability feature of a particular garden. My own perspective is not that lawns are to be done away with completely (even here in the dry SW), because as you said, David, there are some really important uses for lawns. And then there is social sustainability as it relates to environmental sustainability. Some days, I think whatever it takes, so long as we get people outside and engaged in their environment. If it means a lawn for a particular client, and that will get him outside to appreciate the snow geese flying ove head and cottonwood down by the acequia, well great then! And I am with you regarding artificial turf — other than intensively used game fields in places like here, that probably doesn’t make sense, because of the environmental costs associated with producing the stuff. As it turns out, the shaggy natural lawn looking version of artificial turf can also harbor all kinds of bugs if you let other animals have access to it (i.e. dogs, cats, birds defecating). So, there goes the maintenance savings, because you are going to have wash your artificial turf all the time. And you might not want your two year old out there rolling around if they might come away with some kind of skin rash as a result of the cleanser or fungus, or worse!
So, back to natural turf….. Many of my clients desire turf areas, because they have kids or like you said, David, just want a place to play, or hang out in, just like they might want a patio. So, we design and build them — we treat them like a maintenance intensive garden — in fact, we call it that now in our plans and warranty documentation. I don’t know where all you live and work, but here in NM, it’s really hard to maintain a lawn here given the dry heat, intense sun and the soils we have. I originally came from the NE, where you can grow turf grass almost anywhere — it just grows. But here, you need a well-designed and maintained irrigation system, aeration and various strategies to deal with really pernicious weeds and grubs! And if you over water then you have fungus problem. So, it’s a garden, and as I tell my clients, it’s going to take a lot of work by your or someone you pay to keep it healthy.
So, that being the case, what we try to do is recommend turf where it makes sense, i.e. where they are actually going to use it, not just look at it! And then around those turf areas, we put in various foundation planting beds and/or shallow planted swales (hopefully sans cobbles!). Then, all the run-off with nutrients from typical weather will just go from the lawn into the beds to be beneficially used by other plants. Depending on the size of the garden, we might also plant in those beds and swales some of those hardwood trees that will have more of a permanent carbon sink effect. Also, depending how intensive the intended use is going to be, we also might try to use some of the newer native turf types for here such as buffalo grass plugs or a buffalo-blue gramma seed mix. I guess for me it all just comes back to sensitive design, not forcing a black and white issue. Check out some of Joan Nassauer’s (Michigan St, I believe) work in the Midwest reconfiguring suburban lawns to have natural edges.
My last thought is that hot air or no hot air, I think this an important discussion given the fact of climate change and the fact we make landscape for people. But, maybe I should rephrase that as a question though 🙂 …. how would you propose to reduce emissions and increase sequestration through design? How would you incorporate sustainability in a residential design, however you define it? It would be great to here from others on this topic too. Thanks, Heather for getting this going!
PS. Speaking of hot air, I just realized how long this comment is! Maybe bloviation is my stress relief! Tee-hee!