Foliage Hack cause Zwift Crash

There is really no need to sen in crash logs. The errors are extremely easy to reproduce for me:

  1. First set set gFoliagePercent=5 in zwift configs
  2. Open zwift and choose Watopia/fuego flats
  3. Ride or watch another rider. The game will crash after 1-10 minutes

I was able to reproduce this on 2 separate win10 computers. Setting gFoliagePercent to a tiny number maybe helps here but I don’t know,

Well that’s because you’re setting foliage density to 500%. Not the problem at all.


I’m not sure what you are getting at here but foliage density settings is a fairly well documented setting that usally helps a lot with the some of the desolate ladscapes like the desert. If doesn’t impact performance (running > 50 fps on 4k ultra) why shouldn you use it.

The real interesting part is that this bug has been reported as far back as in Dec 19:

  • forum post id: 191676 - Win10 with gFoliagePercent > 5 crash in “The uber pretzel191676

Zwift has known about this for almost a year and they have done nothing. It’s fairly safe to assume they will continue doing nothing

What I’m getting at is that you’re messing with the game’s graphical output manually; with that one in particular you’re increasing the foliage density by a factor of five over what the game is intended to produce. It’s not a setting, it’s a hack. So of course they won’t do anything about that because you’re deliberately changing (and overstressing) the game engine. Complaining when it goes wrong is ridiculous.

Unless every single person that’s having crashes on the latest update has messed with their config file - something I highly doubt - then it’s nothing at all to do with what the current problem is.


Uhm, its not a “hack”, its a well documented configuration option. Also it’s one of the settings you sometimes manually have to tweak since zwift graphics auto detection is not that great and since the low->ultra default settings are… also not that great.

Historically zwift has per default set foliage percent to 200 % for high end pc users. If it thinks you are running running a lower specced machine it will set it to a lower number. My guess is that zwift tweaked this in the last update and now more ppl are exposed to this problem.

I find you comments about “overstresssing” the game engine quite peculiar. User input should never, ever crash a program. The term overstressing doesnt even even apply here since a computer program per default can not be “overstressed”. It’s just a set of instructions, like a cookbook! If the author writes a bad recipe that the computer/chef logically cannot execute the cookbook doesn’t get stressed. Sure the hardware running the program/recipe can be “stressed” but this is is not the case here since at least in my case cpu and gpu doesnt even get close to maximum utilization.

Think the issue is this isn’t a typical user input since it’s not a selection within the game settings. You have to go find the files and manually edit them. Hence it’s somewhat of a hack. And even ZwiftInsider says editing the config files may cause issues with your game:

Edit: from the ZwiftInsider article further down:
Sets the level of auto-generated scenery – trees, grass, flowers, fruit, underwater kelp, etc.

This is a very effective way to manipulate the environment to suit your preferred FPS.

A number between 0 and 1 is normal.

Higher number increases scenery density / realism but decrease FPS.

Lower number decreases scenery density / realism but increases FPS.

Examples: * 0 = 0% * 0.25 = 25% * 0.5 = 50% * 0.75 = 75% * 1 – 100% * 5 = 500% – be very careful!"


They are only referring to fps here. Please mind that the game has been working perfectly for me for the last 2 years or so with these settings (until France map was introduced, and yeah the uber-pretzel did crash for me this spring). These are user inputs since they are configurable by the user, a “hack” would be firing up the old hex editor to increase the number of randomly placed rocks and such.

And lastly, why are we even having an discussion about gFoliagePercent? The problem is that the game crashes. I’ve provided our dear zwift support people with a reliable way of replicating the problem. If they cant fix it they should just remove randomly generated foliage from the game. Maps like New York that don’t have random foliage have no issues with crashing

On High and Ultra profiles, foliage density is 100%. That’s why it’s not even in the config file by default. The lower profiles only change it down from 100% to improve the frame rates on lower-specced systems; down to 50% on both Medium and Basic. So I’d say going to 500% is quite likely to cause issues. :rofl: If it’s a configurable user option, why isn’t it in the game menu? You may have forgotten if you’ve been editing for years but the .txt config files aren’t even user editable by default, you have to allow write access permissions in the file properties. So yeah, it’s a hack.

PS: did you actually read the thread you mentioned from December? The first reply is from the chap who wrote ^that guide to editing the config files… :wink:


Is it documented on Zwift’s own website?

Just because it’s documented on third-party websites, and because it might have worked before, doesn’t necessarily mean that it’s a supported option.


There are threads on this support forum where people with newish gpus are recommended to manually edit the configs to get ultra settings and among other things set gFoliagePercent=2. If its recommended here how much more official can it get?

And as an open question, if “hacking” your config and setting foliage to zero fixes the issue does that absolve zwift then? Is that an acceptable solution to you you people?

No, because this implies the default foliage value is causing the issue. It isn’t. It’s your super high foliage value causing the issue.

Now, if you edit your config file back to the normal ultra value (1) and Zwift still crashes on those routes it is indeed an issue with the latest update.

I’ve ridden Tempus Fugit since the latest update and had no crashes with default foliage. So it seems the issue is your manual edit.


There is no official Zwift communication that you can hack the pref file. If this hack causes issues and more people does it I would think Zwift will close the file so you can’t hack anymore. Just because it is hackable does not mean you can do it safely.

There is many hacks out there to modify your car’s computer chip to get more performance but it your engine blow up it is your problem.

I started a new topic to keep it all together.


This is a community forum where 99% of the posts are from users rather than Zwift employees. I’ll be very surprised if you can provide a link where any config file amendments are officially documented.


But regardless of my previous settings. I’ve had the exact crashes described in this thread. For me the crashes are fixed by setting gFoliagePercent=0.5… Can we have any confirmation/denial from someone else who has actually experienced the problem that this fixes the issue?

But you’ve reported a crash in Watopia. The other crashes are happening only in France as far as I’m aware. So it’s likely that your crash isn’t the same.

Solved it!

Did some rides today on France map with some different settings:

  • set gFoliagePercent=2 - game crashes 15 seconds into group ride
  • set gFoliagePercent=1 - game crashes 15 minutes into group ride. This was the Zwift Riders Germany Gruppenfahrt. Absolute carnage. Pretty sure leader vas booted from this ride
  • set gFoliagePercent=0.5 - Yay! First time ever being able to ride on france map for more than 10 minutes or so. Sucesfully completed a 45 km ride!

So. Solution is to “hack” zwift and set set gFoliagePercent=0.5.

My Zwift crashed twice in France last Saturday. I have never changed gFoliagePercent and it seems to be 0.5 and yet Zwift crashed.

My Zwift didn’t crash in France the other night and my foliage setting is default (i.e. 1; 100%). It’s a red herring.


Have you tried upping foliage then? How is it a redherring when i can successfully complete a ride only by setting to something lower than default. Do you even know the foliage settings you are using?

You do know that a majority of zwifters do successfully complete their rides using default values right? It would be interesting to se if someone with a goldilocks setup can tweak it into to the bad zone. So, please make some tests yourself. Then dismiss my findings

@Anders_Larsson2 - Please keep the Foliage Hack to this topic.

It is distracting from the Zwift Crash forum post.