To add immersion and create some random minor event in the world that can have some realistic impact on human (player) development or create period of scarcity, low yield and tensions between region, increasing trade of goods between regions, it can be cool to add some random event, like climatic seasonnal event i propose.
In winter, some year it can happen a more harsh winter with low yield for crops, low reproductiv rate for animals, and make some trees dying.
In summer, some year it can happen a more dryer summer (heat wave) with low yield, lost of crops, lost of cattle, and make some trees dying.
For instance, the game can trigger a harsh winter (or summer) once 2 or 3 years (in-game) on a regional scale or on a single server scale.
The result will create an event windows (like those little ingame event that happen when crafting) with a text that announce there will be a harsh winter/summer in your server area.
A code can simply select randomly some trees ID across the server to replace them with a very low quality tree <10 with the dying, dark leafless 3D model. And maybe a forced aging tree's rate.
It will chose a certain quantity of tree ID randomly in the wild and also in player claim, affecting tree nursery planted by guilds, forcing forester to manage, cut and replace dead trees.
The quantity of tree have to be balance to not create large dying forest but simply few hundred tree.
For players crops only in summer the code will cut in half some tiles of crops, randomly across the server.
In summer, a heat wave event will also make tree dying and switch randomly to low quality dead trees.
The code will be a random dice roll and some guild will not suffer from the event and some other guilds will suffer a little more. It's all about luck.