Fig. 1. Map of Knox and Daviess Co. where soil samples were collected for a county-wide survey with emphasis on the Eolian sand deposits and on two farms in Knox Co. 16 km south-southeast of Vincennes. Light blue areas represent Eolian sand deposits, dots represent sample locations: no root-knot nematodes (blue dots) and root-knot nematode present (red dots). The triangle indicates the location of Vincennes, IN.
Image from Plant Health Progress article:
Distribution and Damage Caused by Root-Knot Nematodes on Soybean in Southwest Indiana