Board Thread:Suggestions forum/@comment-31735895-20170417000134/@comment-26172435-20170417071942

As these features are lore based, they can be considered planned, but since you appear to be focussing on how to get them implemented, a suggestion like this might add to the mod teams efforts.

The OId Forest biome already generates rivers, but there is no predefined Withywindle on the map. If that would be added, Mevans could simply increase the occurence rate of willows to make its banks get covered with them:

this.decorator.willowPerChunk = 2;

Current maximum value for this parameter in the mod is 3. I reckon with a value of 4, the river banks in the Old Forest will be dominated by willow trees.

Alternatively, Mevans could create a dedicated Withywindle biome, but I don't think the added value would justify the work.

A unique water spirit Goldberry could be added to the area around the upper reaches of the Withywindle once that river has been added to the map.