Shaped a little like Buttersworth, Malaysia

Darn. WIsh I could help you. Maybe I've gotten used to it, but indeed it's an issue.

I just tried Wolfgansee's Austria and realised that it has the same problem as this, but it uses multiple trees like you described to hide it. Thanks for the help!

I'm guessing that you probably have BloodyPenguin's Extra Landscaping Tools (who doesn't), so I suggest using the tree brush to place less intricate trees of various sizes among the existing ones. The thicker the foliage, the better results you'll get. This is a great little pack here by Lost_Gecko: https://steamhost.cn/steamcommunity_com/sharedfiles/filedetails/?id=931378862 This one's a bit dark but it's a native to Spain and has decent LOD results
Ever since learning this, I've been using multiple sizes of trees in maps with custom trees. It's a ton more work, but it looks so much better, so it's worth it. See these screenshots for example https://steamhost.cn/steamcommunity_com/sharedfiles/filedetails/?id=1111828158

Shoot Yes, that's what I experienced, too. It kinda drives me nuts. It's a limitation of the game when it comes to trees, because tree LODs are automatically generated. We're not able to make custom tree LODs.
So on top of that mod, the following is the best solution we have. First, check to see if you've got the graphics settings (texture especially) on high. Then, as the mod says place trees of different sizes and it tricks the eye, visually blending out that very stark change into LOD that we see here. As the mod says, LOD distance is triggered based on tree size. continued...

Sadly nothing has changed for me no matter how far I set the distances up.

here the middle trees have good, normal textures if zoomed in enough
https://steamhost.cn/steamcommunity_com/id/NeoN5812/screenshot/901148415696677607

but then if I zoom out one...
https://steamhost.cn/steamcommunity_com/id/NeoN5812/screenshot/901148415696677960

Is this what you were experiencing? It's really hard to ignore.

Tried offsetting a little as you said
https://steamhost.cn/steamcommunity_com/id/NeoN5812/screenshot/901148415696676787

and fully maxing it out with no results.
https://steamhost.cn/steamcommunity_com/sharedfiles/filedetails/?id=1231123861

Am I doing anything wrong?

Thorough reply! I'll test it out and report back.

These count as big trees Now that i know how the tree LODs work, I'm only using this big tree now and then instead of the entire map. I love it because it covers more area with just one tree. So I was thinking less total number of trees = better performance, but it gets more complex than that :) Live and learn.

That's down to the tree itself.. I notice it on these trees as well, but I found a solution. I've got a laptop, so I only use this mod for tree LODs because of my computer. Put the setting just a little further out and the LOD of these trees is a *lot* less noticeable. https://steamhost.cn/steamcommunity_com/sharedfiles/filedetails/?id=625608461
"Adjusts LOD distance for trees depending on their size. The larger is prop/tree, the further it is visible! In vanilla game all tree models get replaced with LODs at the same distance. This mod fixes that and now tree LOD distance depends on tree size. That fixes pixelated LODs of large trees like Siberian Pine by MrMaison. That may also increase FPS if lots or small trees (like bushes) are used (because they get replaced with LODs earlier)."

Not as bad on normal maps?

I love this map design but using minimal mods, no assets, this map and the required items and monte belo there's an extremely shallow LOD render distance. If I'm not completely zoomed in on trees they have terrible, terrible textures :(

Nunca esperaría encontrar mi ciudad como mapa en este juego, toca probarlo!

힌샙숱봘똘

YUp, I found the problem when changing the roads on this map, and fixed it for this map. I'll fix the main one asap

Did you fix the GHOST stop sign issue? Anyways nice map will give it a try on my next city build. Thanks for the massive efforts you seem to put into all your maps and keep up the excellent creations. :-)