The Weakley Flora Map Key
The Weakley Flora contains maps showing the distribution of most plant taxa, using symbols to
indicate abundance and whether or not it is exotic within a particular region of the map. The maps are not the familiar county-level dot maps of Radford, Ahles, and Bell, which would
require far too much investigation and introduce errors of omission for the large flora area.
Instead, the regions of each map correspond to the combination of state and physiographic province (e.g., coastal plain, piedmont, mountains, and interior low-plateau).
Each symbol is based on published distribution maps and distribution statements in other floras, amended and improved by additional herbarium specimens and published records (such as the "Noteworthy Collections" section in the journal Castanea).
Note that the very small areas of the DC Piedmont, the DC Coastal Plain, and the DE Piedmont are not shown separately from the MD Piedmont, the MD Coastal Plain, and the MD Piedmont, respectively. The native/alien status of the taxon is shown by squares for native occurrence and triangles for alien occurrence. Note that some species have distributions including both alien and native distributions, so Dionaea muscipula for instance is native in the Coastal Plain of NC and SC, but alien in the Coastal Plain of FL. The abundance in that state × physiographic province area is shown by the symbol, an open symbol is rare, a symbol with a dot is uncommon, and a filled symbol is common.
In the lower right corner is a space designated for distributional information. If the species is endemic to the Flora Area, you will see "EN." If the species is alien, you will see the region of the world to which it is native. If the species is native but not endemic, you will see a compass rose. Eight arrows depict the native distribution of the taxon outside of the Flora area. Arrows can be long (common at least somewhere in that region), or short (only uncommon or rare in that region).
The regions to which the eight arrows point are:
- N arrow -- ne. North America (PA and n. NJ north to the Canadian maritime provinces, west through QC to se. ON and e. and s. OH);
- NW arrow -- nw. North America (w. OH, MI, w. ON, and NU west to AK, BC, and OR, north of and including n. MO, NE, WY, ID, and OR);
- W arrow -- w. United States (the western “Southeast” of trans-Mississippi LA, AR, s. MO, OK, and e. TX), west to sw. United States;
- SW arrow -- Mexico, Central America, and South America;
- S arrow -- peninsular FL;
- SE arrow (dashed to indicate oversea) -- West Indies (including Bahamas) and Bermuda;
- E arrow (dashed to indicate oversea) -- Asia and/or Africa;
- NE arrow (dashed to indicate oversea) -- Europe.