I really think it'd be cool to pattern the logo after the definition of something like "agriculture" (below, when i do a search for agriculture on google). The metaphor of agriculture, horticulture, etc, is great for this and perhaps the imagery of seeds or growth within organizations could be great.
the science or practice of farming, including cultivation of the soil for the growing of crops and the rearing of animals to provide food, wool, and other products."
But in our case it'd obviously be something like
the science or practice of cultivating authentic cultures... for organizations, teams, communities and the individuals who comprise them.
The logo needs to work horizontally in writing...
It'd also be nice if it incorporated a distinctive mark in, much like the "winked" face found in my former company, http://www.deliveringhappiness.com.
Finally, it'd be cool if you could tell this org was focused on WORKPLACE culture in addition to the agriculture/horticulture metaphor...