* Cover Crops - Living Mulches* Plants for a future -- Useful weeds* Good Weeds—it has an especially good list of "soil indicator" weeds* Insect Olfaction of Plant Odour
*Cover Crops - Living Mulches==External links==*Plants for a future -- Useful weeds*Discover Beneficial Weeds in the Garden—it has an especially good list of "soil indicator" weeds*Insect Olfaction of Plant Odour