A group of scientists and food activists is launching a campaign to change the rules that govern seeds. They are releasing 29 new varieties of crops under a new open source pledge" that is intended to safeguard the ability of farmers, gardeners and plant breeders to share those seeds freely. The new Open Source Seed Initiative will pass out 29 new varieties of 14 different crops, including carrots, kale, broccoli and quinoa. Anyone receiving the seeds must pledge not to restrict their use by means of patents, licenses or any other kind of intellectual property. Any future plant that is derived from these open source seeds also has to remain freely available as well. Irwin Goldman, a vegetable breeder at the University of Wisconsin, Madison, ... doesn't like the consequences of restricting access to plant genes - what he calls germplasm. "If we don't share germplasm and freely exchange it, then we will limit our ability to improve the crop," he says. Sociologist Jack Kloppenburg, also at the University of Wisconsin, has been campaigning against seed patents for 30 years. His reasons go beyond Goldman's. He says turning seeds into private property has contributed to the rise of big seed companies that in turn promote ever-bigger, more specialized farms. "The problem is concentration, and the narrow set of uses to which the technology and the breeding are being put," he says.