Orion Magazine - March/April 2009

they created a Fannie Mae–backed mortgage that took location into account when determining a home buyer’s credit limit. Neighborhoods in a few cities were rated using demographic, land-use, and transit characteristics; homeowners applying for mortgages in location-e;cient areas were able to qualify for larger mortgages. Pilot mortgages were issued, and in 2002, after two years, none had defaulted.

In today’s credit crisis, the movement has shifted away from designing mortgage products and toward in?uencing the course of development. To that end, the Center for Neighborhood Technology and transit-oriented nonpro>t Reconnecting America, with support from the Brookings Institution, have developed a tool for quantifying location e;ciency.

“Transportation is the second-highest cost for most households,” says Dave Chandler from the CNT. “The Housing + Transportation Index is a tool that a lot of planning departments are using to say: ‘If we’re going to build housing, where would it have the best overall impact for the people who live there and for the community, in terms of being able to reduce tra;c congestion and air pollution?’”

Used online, the interactive H + T A=ordability Index ( htaindex.cnt.org) lets you select from a drop-down menu of > fty-two metropolitan regions. A map shows the area—block by block—color-coded for a=ordability using the traditional standard (housing = less than 30 percent of median income). Then you can switch to a map showing what’s a=ordable according to the new housing plus transportation standard (housing + transportation = less than 45 percent of median income). The maps look very di=erent. Looking just at housing, the fringes of metropolitan regions are the only a=ordable areas. Looking at housing plus transportation, the inner belts and transit corridors are the a=ordable parts of town.

Home buyers often look at school quality, crime rates, and neighborhood ameni-

ties in shopping for a home, but rarely do they factor in the cost of getting around. Is having a somewhat bigger yard worth an extra $4,000 a year in transportation costs? If people at every level of the housing process—planners, developers, sellers, bankers, buyers—become more aware of how transportation a=ects a=ordability, we may just stand a chance of not only undoing half a century of gov-ernment-funded land-use disasters, but of developing communities that are greener, more livable, and—bonus!—less subject to catastrophic >nancial collapse.

Zoning Out

by louise ducote

My gardening life began in 1990, the same year the United States Department of Agriculture (USDA) revised its 1965 Zone Hardiness Map for cultivated plants. The zones, so conveniently mapped out on the back of your average seed packet, are based on lowest temperatures and duration of cold, landing the interior of Alaska in Zone 1, Hawaii and southern Florida

in Zone 11, and my own dear-but-sweltering Austin, Texas, in Zone 8. If you live in Zone 5 and purchase a plant with a tag that reads “Hardy to Zone 7,” you’re taking a chance. That doesn’t prevent nurseries from peddling zone-inappropriate plants, or hopeful gardeners from gambling.

The 1990 map drew from data gathered between 1974 and 1986, a lifetime ago if you’re a polar bear, a salamander, or Al Gore. The USDA continues to use the 1990 map as current, though they maintain that a new one is pending. Not willing to wait, in 2006 the National Arbor Day Foundation published its own revised map using data that showed winter lows increasing as much as eight degrees in some places. According to the foundation, the old zones have marched alarmingly northward. Cities like Washington DC (once Zone 7, now basking in 8) that have resisted classi>cation as “southern” will have to relent, just a little, as gardeners experiment with previously unthinkable Confederate fare like the southern magnolia tree.

The plant industry has resisted the zone changes for a more traditional reason: money. Most nurseries o=er a money-back guarantee on plants that die within a year of purchase, and they’re less likely to have to pay out on the DC gardener’s choice of a cherry tree than they are on a magnolia. As the world heats up, plants that need a certain amount of cold to thrive are struggling. After thousands of years of success, the sugar maple is now panting in New York, producing less sap and becoming more susceptible to pests and fungal disease. But that failure to thrive is not as likely to be evident during a plant’s >rst year as the failure that leaves a “hardy to Zone 8” plant black and frozen on your Zone 6 ground.