For this study, we have developed a four-level hierarchy of Greenlands protection, based entirely on the degree of "security" that various Greenlands features receive through provincial and municipal policy instruments. This hierarchy is based on a combination of:
- legal protection through government policy instruments and legislation;
- patterns of historical development and land use changes in south-central Ontario (that is, the Greenland types that have typically been protected and those that have not);
- consultation with municipal planners from the 14 single- and upper-tier municipalities on the extent to which Greenlands are protected as a consequence of urban development.
The four different levels of protection we have given to Greenlands in south-central Ontario are:
- Level 1: Fully Protected
- Level 2: Generally Protected
- Level 3: Partially Protected
- Level 4: Not Protected
When we refer to Greenlands protection in this context we are talking about the degree of protection given to specific natural heritage features or areas that have been inventoried and designated as significant by some authoritative body as worthy of at least some form of protection. Some such lands are classified in this study as "Not Protected" (Level 4), but these unprotected Greenlands should not be confused with lands that have no Greenland designation whatsoever, which of course also have no protection. These latter lands are shown as pale grey on the accompanying maps. They are primarily cleared agricultural land, although they are not necessarily currently under cultivation.