A minute ticked by, and he heard nothing further! Without the knowledge of the Harkonnen overlords – who were only on Arrakis to mine the spice, and viewed people only as a resource to be squeezed – Kynes oversaw armies of secret, devoted workers who planted grasses to anchor the mobile dunes; these Fremen established groves of cacti and hardy scrub bushes in sheltered canyons, watered by dew-precipitators.