Landscape - splitting ISM into smaller ones

Hi there,

Right now we have multiple levels in our project, and each level has a landscape. On each landscape, we have a lot of Foliage Types and lots of instances per type (stored automatically into InstancedStaticMesh, ISM). It seems that UE groups all instances of the same type on the same component, so if we have like 3000+ rocks or trees or anything, with collision, when the level streaming initializes a single component it takes a long time since it has those thousands of entries.

Is there a way to split an ISM into multiple ones, automatically, within the landscape tools? What else can I do to improve those components register (also unregister) times?

Thanks in advance