Click on the following list of common plant species links to see trend figures and distribution maps.
(See descriptions below)


Trend Figures:

Trends in abundance. Bar heights show mean abundance of a species at all sites where it was ever observed, even when not observed during a given CTAP cycle (five years).  Error bars represent 95% confidence intervals (bootstrapped).

In the first CTAP cycle (1997-2001), data were collected from 133 forest sites, 128 grassland sites, and 139 wetland sites.
In the second CTAP cycle (2002-2006), data were collected from 150 forest sites, 149 grassland sites, and 149 wetland sites.
In the third CTAP cycle (2007-2011), data were collected from 149 forest sites, 136 grassland sites, and 138 wetland sites.
The fourth CTAP cycle is ongoing (2012 - present). The results through 2014 are summarized here, during which time data were collected from 90 forest sites, 84 grassland sites, and 77 wetland sites.


CTAP sites where each species was observed across Illinois, through 2014.