Colorado's unregulated marijuana grow sites persist despite legal 'green rush'

Down in Colorado's Front Range, the cluster of towns and cities that cling to the eastern edge of the Rockies, the scent of what has been dubbed a commercial “green rush” is hanging in the air – literally. On the road in from Denver airport, several of the state's estimated 800-900 legal growers have taken advantage of cheap warehouse space to open sophisticated indoor facilities, whose odour is clearly discernible by passing motorists.