Find Out How Your Lawn Measures-up

Photo © Adam Kerfoot-Roberts

In 2015, the California Water Commission, responding to years of severe drought in the region, set new limits on landscapes surrounding newly constructed buildings, such as houses, businesses and schools in California. The revised ordinance limits grass to about 25% of a home’s combined front, back, and side yards in all new construction. We were so inspired by these new rules, which took effect Dec. 1, 2015, that we decided to build in some features to our new groups tool to help everyone, not just Californians, challenge themselves to meet these new lawn standards.

landscape plan

Photo © Jay@MorphoLA

While existing landscaping is not subject to this new rule, anyone embarking on a significant renovation of their landscaping (more than 2500 sq ft) will also have to keep lawn size to less than 25%. New commercial, industrial, and institutional buildings are encouraged to skip lawns entirely.

The ordinance is expected to reduce the water use of a new home by about 20% or about 12,000 gallons a year. Water use on new commercial landscapes will be cut by about 35%.

While California is primarily interested in reducing residential water use (landscaping is a HUGE contributor to overall household water use), this is also a great opportunity to rethink landscapes as wildlife habitat. There is mounting evidence that yards with more complex vegetation–trees and shrubs along with herbaceous plants–are associated with a greater diversity of native bird speciesopen_in_new. This ordinance may give people the push they need to plant more trees and shrubs native to their region, giving wildlife a boost in their yards.


Photo © Cornell Lab of Ornithology

But wait – this is not the measure California is looking for! On the groups page (explained below), you will see just how they want you to measure the size of your lawn.

In this project, we have given you several ways to “measure” your own lawn. The easiest is to look at your Site Overview, which contains a handy pie chart showing a break down of your map by habitat-type. In the image above, you can see that lawn takes-up 8.8% of this site. The pie chart shows you the proportion of each habitat polygon on your map in relation to the entire area of your site, as measured by the “site line.”

HINT: This will only be true if you have outlined your entire property.

Photo © Rebuilt from a graphic originally produced by Lorena Elebee (LA Times)

The new California regulation requires that your lawn be 25% of the landscaping, not 25% of the entire area of your property. Thus, their measurement excludes other features on a site typically covered with “Building” and “Pavement” habitat polygons on a habitat maps. On the groups page, you will see just what California wants you to manage for. To the right of the bar charts, “Habitat Breakdown”, we provide a new calculation that shows your lawn size as a proportion of just your landscaped area.

Special Access

We’ve set-up a special group for you to join, just to help you access this calculation. It is called the Measure Your Lawn Group. You can find it by searching under the Groups or by following this link. You’ll need to sign-in and have a habitat map completed to join the group and get your calculation.

Screen Shot 2015-12-02 at 4.04.16 PM

Photo © Cornell Lab of Ornithology

On the groups page we provide a new calculation that shows your lawn size as a proportion of just your landscaped area. It excludes both buildings and pavement. So, if you want to try and meet the new California standard, use this number in the groups pages.

Tell us how much lawn you have


Photo ©

First, find the lawn habitat tool to use on your map. It is located in the Tool Shed under Second. Find lawn on the toolbar that pops up and click it once to select it then click on the map where you’d like to start to draw and click to trace around the lawn on your map. You can always change its size and position using the lock/unlock from editing box. To get accurate data on the size of your lawn, zoom-in to follow contours on the image and make to sure you close gaps between the different habitats on your map.


Photo ©

Double click on the lawn to add important data and show off your conservation efforts. You can give your lawn a name or title in Basic Information. Then click Characteristics to tell us about it. What kind of mower do you use, what do you do with the clippings, and how often do you water? Don’t forget, you can also make comments about the lawn and upload pictures of it. Show us how your lawn is being put to use.