See this:
ForestryMC/ForestryMC#1574 (comment)

Using Biome Bundle Version: Biome Bundle for 1.10 Forge (v4.1)

A new version of Biome Bundle can be downloaded from Curse (Forge) or Github (Bukkit). I expect this version to fix the issue you are experiencing, a brief changelog can be found here.

Biome Bundle is now dependant on Open Terrain Generator and the installation process has changed; head over to the installation instructions that detail how to install Biome Bundle.

Please bear in mind you will need to generate a new world with the latest update as it is not compatible with old worlds.

Happy Exploring! ☻