Pokepark ground textures?

[Random Talking Bush]

The *.DAC/*.DAN files are what you're looking for, the area models have "Res" at the end (so for example, Ar01Zn01Res.dac). If I recall correctly (I've already unpacked them all for my collection), you'll need both NTCompress.exe to decompress the files, and and any program that can work with U8 ARC files (like U8Mii) to unpack them, then they'll just be in the BRRES files as usual, which either BrawlBox or BRRESViewer can open.