Last February we got melancholy about Arbor Day on seeing how drastically plant hardiness zones were changing, of late, in response to climate change. A modern extension of that platitude that you "can't ever go back home," apparently, is that certain of those glorious flowers of childhood memory may soon exist only in the landscape of our dreams (pictured: Texas Bluebonnets). Fanciers of official US state flowers and trees will find their recollections digitally planted on the National Wildlife Federation's Gardener's Guide to Global Warming. Like windows eternally open to spring, the internet can stitch our emotions to the present. Click twice, plant once.