Why Rock Lawns Are Bad for the Earth

Kill your lawn, but don’t replace one problem with another

For years Dr. Travis Longcore, a geographer and professor at USC’s Spatial Sciences Institute and co-founder of the Urban Wildlands Group, could be heard on local PBS radio programs and elsewhere, earnestly encouraging homeowners in our dry climate to “kill your lawn.” The refrain certainly got people’s attention, but few other than card-carrying members of the California Native Plant Society took his admonitions seriously. Finally in about 2009, several local communities in the City of Los Angeles began to understand the importance of local sustainability and started addressing the impact of wasteful water habits on the environment.

The Mar Vista Community Council Green Committee organized a Green Garden Showcase that year, hoping to convey the idea that removing a lawn was an opportunity, rather than a hardship, and best done with nature’s processes in mind. More than 400 gardens were opened to the public during the next seven years of this annual spring one-day event.

“Simply covering the former lawn area with rocks and drought-tolerant plants is a missed opportunity,”

Mixed rock and soil is okay, but needs pollinator plants.
Mixed rock and soil is okay, but needs pollinator plants.

lamented Sherri Akers, a Mar Vista Community Council Board member and one of the co-founders of the Green Garden Showcase. This became apparent to those who took the tour, and in response, “Community members created lush, livable spaces that support our pollinator habitat. Best practices feed aquifers and reduce the loss of water running off into our storm drains,” Akers explained.

Simultaneously, the Los Angeles Department of Water & Power (LADWP) began rolling out a grant program to fund efforts to educate the public about the importance of replacing lawns with native plants that are not only drought-tolerant, but that support songbirds, butterflies and other local wildlife that can thrive in a home garden. The campaign included promotion of a significant rebate program whereby residents would be paid to replace their water-hogging grass lawns with plants and other materials that would help cut the city’s water use.

As this idea caught on, several start-up companies realized the rebate incentives could provide a tidy

Rock blocks rainwater drainage and holds heat.
Rock blocks rainwater drainage and holds heat.

profit, and began offering residents services to replace the lawns and complete the bureaucratic paperwork required by LADWP. Nobody anticipated the proliferating cookie-cutter designs that replaced lawns with environmentally unfriendly hardscape—decorative rock, gravel, decomposed granite and synthetic turf, which retain heat and prevent water from soaking into the ground. Yes, water bills would drop, but other important sustainability measures, such as those stressed by Akers and her Mar Vista neighbors, were being ignored. Far from being an improvement, the replacement “lawns” were likely exacerbating the problem.

But there’s a happy ending to this sad tale. Ultimately the rebate program was halted, and now, thanks to leadership from L.A. City Councilmember Paul Koretz, LADWP hopes to have approved a new set of standards for a $1.75/sq. ft. rebate. The Board votes in early August.

The new standards follow the Watershed Approach to landscaping: healthy living soil, rainwater as a resource, climate-appropriate plants, and highly efficient irrigation when necessary. As a result, future retrofits must include organic matter mulch as well as an element of rainwater capture in the soil in order to qualify for a rebate.

Instead of excessive rock and gravel and certainly better than synthetic turf, biologists say it’s better to

Abundant pollinator plants and exposed soil encourage growth of microorganisms and ground bees.
Abundant pollinator plants and exposed soil encourage growth of microorganisms and ground bees.

have bare soil, which allows water to soak into the ground for groundwater recharge. It also creates an opportunity for solitary native ground-nesting bees, which are very important pollinators.

Some landscapers suggest mulch because it inhibits weed growth, but the most common varieties, redwood and eucalyptus, alter soil characteristics, which then inhibits the growth and health of many native plants. However, the city program will require a mulch component, so it’s important to choose elements that are in tune with the earth.

Killing a lawn doesn’t mean destroying the natural life, but finding a more harmonious way to sustain it.

 

 

 

 

 

 

 

This article is a part of the August-September 2016 Success with Integrity issue of Whole Life Times.