It's not unreasonable. Perennial grasses are notorious for allelopathy, especially directed toward tree seedlings. That is the chief reason new tree plantings have those circles of mulch around them. As the roots become more extensive, there is no reason for mulch patches. But prairies and forests have a constant battle for territory at the boundaries. Trees will shade out grass and forbs but they also produce some allelopathic chemicals in roots and leaves with black walnut and tree of heaven some of the most well known examples. Annual grasses show little evidence of allelopathy. I would not be surprised if relatively low and slow growing plants like bulbs did not exhibit allelopathy or at least were immune to it and able to piggy-back on 'companion' plants that were allelopathic. _______________________________________________ pbs mailing list pbs@lists.pacificbulbsociety.net http://lists.pacificbulbsociety.net/cgi-bin/…