an incorporated, non-profit, multi-agency organization founded in April 2007 by a group of individuals and organizational representatives who saw the need for a coordinated provincial response to the growing threat of invasive plants.

Invasives Canada - Canadian Council on Invasive Species

dedicated to safeguarding Canada’s ecosystems, communities, and economies from the growing threat of invasive species. As a national network of chapters, partners, and interested parties, we lead collaborative efforts to prevent and manage invasive species while promoting sustainable land and water management.

Ontario Phragmites Working Group

formed in December 2011 by dedicated professionals concerned about the growing threat posed by the aggressive invasive Phragmites australis to biodiversity, Species At Risk (SAR), recreation, tourism, infrastructure, and property values.

Although its in Toronto, I guess it still covers Ontario. Likely there aren't many other groups or resources for Ontario.

The Toronto Entomologists' Association (TEA) welcomes everyone who is interested in the insects of Ontario. We are an association of mostly amateur entomologists. Although our meetings are held in Toronto, we extend far beyond that in our field trips, our membership, and our seasonal summaries. Come to our meetings, join us on our field trips, purchase our publications, apply for the research grant, join us! The TEA is a registered charity and a non-profit educational and scientific organization formed to promote interest in insects, to encourage co-operation among amateur and professional entomologists, to educate and inform non-entomologists about insects, entomology and related fields, to aid in the preservation of insects and their habitats and to issue publications in support of these objectives.

Waterfall photos and videos by Freaktography, the Ontario urban/ rural explorer.

"A not-for-profit volunteer organization dedicated to the health of urban forests in the province of Ontario".

Related groups:

Forests Ontario "Supporting forest restoration, stewardship, awareness and education".

Take Root Part of Forests Ontario.

Grasslands Ontario