A Seattle zoo said it is canceling its spring "Zoo Doo" fecal compost sale due to high levels of herbicide in the manure blend. That's Crappy! Woodland Park Zoo officials said unacceptable levels of the herbicide clopyralid were detected in the compost, which is comprised of manures from several animals, straw bedding, wood chips, leaves and grass, the Seattle Post-Intelligencer reported. "We deeply regret that Zoo Doo will not be available for our many loyal users," zoo representative Dan Corum said. "Gardeners can be assured that they will get the quality they expect from Zoo Doo when it's available again this fall." Officials said the Zoo Doo will be used around the zoo, as clopyralid is not dangerous to the animals. They said the sale was canceled because the herbicide could kill some of the garden plants that it is meant to fertilize. Woodland Park Zoo spokesman David Schaefer said the facility sells about 1 million pounds of Zoo Doo each year to several hundred gardeners who are chosen by lottery.