Hi Forester1
You can find some details on the TurfFX on our wiki here, including some video tutorials (note they are from the first release of TRS19, so there's a little more in the effect layers interface now!):
https://online.ts2009.com/mediaWiki/index.php/Help:TurfFX_Effect_Layer
For a bit more on the Effect Layers in general, this page has the basics and links to each effect layer type:
https://online.ts2009.com/mediaWiki/index.php/Effect_Layer
Effect layers are essentially 'paintable' effects for routes. We currently offer 3, TurfFX (which is animated procedural grass), ClutterFX (essentially scenery objects specified as 'clutter'), and Water Effects (the new WIP water system, which is currently in an early implementation in TRS19 SP4 and newer).
To use these you will need to use the new Effect Layers menu, rather than the Surveyor tabs (or asset list in Surveyor 2.0). However there are a few various preset assets for TurfFX to get you started, as well as the 'TurfFX' assets themselves (which configure the colour of the grass, along with it's general shape), which will be shown in the Effect Layers tool.
The main thing is that these can be 'painted' onto the route, like you would paint ground textures. Or alternatively you can specify ground textures to bulk apply the effect layers onto; this then allows you to very quickly apply them across a route; then simply remove it where you specifically don't want it.
Regards
Zec