- All American Plant Selections
- Colorado Federation of Garden Clubs
- Colorado State University cooperative extension
- Colorado Native Plant Society
- Center for Invasive Plant Management
- Plant Select
- Planttalk
- Denver Botanic Gardens
- Denver Rose Society
- Colorado State Forest Service
- CSU Turfgrass
- Colorado Dahlia Society
- Colorado Gardening
- Boulder County Audubon Society
- Colorado County Birding
- Beginners Guide to Earthworms
- Colorado Bugs
- Biological Control Organisms for Insects and Mites