Actually, the ground is two textures. One for the base (brown spots, bottom) and one for the detailed area (green grassy area, top).
I used jabo's plugin to make those. Turn on anisitropic filtering, then switch to RGB emulation. It'll give you the effect, but is slow. Another way is to use glide64 and evoodoo then turn off filtering in evoodoo's config. But since evoodoo doesn't support multi-texturing, you'll only see the base texture.