Table 1. Distribution records used for modeling of common ragweed (Ambrosia artemisiifolia), perennial ragweed (A. psilostachya) and giant ragweed (A. trifida).

	Common ragweed	Perennial ragweed	Giant ragweed
North American occurrences	2,284	1,531	1,985
European occurrences	4,127	248	364
Total	6,411	1,779	2,349

Notes.

The dataset include North America distribution records from the GBIF online database (http://data.gbif.org). MAXENT automatically removed duplicated presence records defined as records in the same 10’ grid cell.