USDA Plant Hardiness Zone Map (Image: USDA)
On Wednesday, the U.S. Department of Agriculture released an updated guide for the color-coded map of planting zones often seen on the back of seed packets. Half of the cities included on the guide are now in warmer zones, which many are saying reflects global warming.
The headline used by the Associated Press was “New map for what to plant reflects global warming”.
But AP reports later in the article that USDA spokeswoman Kim Kaplan, who was on the team that created the map, didn’t want the new zones on the to be associated with global warming. AP reports Kaplan as saying even though some areas of the country are now in warmer zones, the map “is simply not a good instrument” to be used to support global climate change. Kaplan says this is because the map is based on the coldest days of the year, not average temperatures.
On the flip side, AP goes on to report David Wolfe, a professor of plant and soil ecology at Cornell University, as saying that the map clearly reflects global warming:
The revised map “gives us a clear picture of the ‘new normal’ and will be an essential tool for gardeners, farmers and natural resource managers as they begin to cope with rapid climate change,” Wolfe said in an email.
According to USDA’s press release, which does not mention the words “global warming” or “climate change,” this update to the plant hardiness zone map comes two decades after the last update in 1990. The new version of the map includes 13 zones, with the addition for the first time of zones 12 (50-60 degrees F) and 13 (60-70 degrees F). Each zone is a 10-degree Fahrenheit band, further divided into A and B 5-degree Fahrenheit zones.
By Liz Klimas, The Blaze