After placing down floating agricarnations, stacked and not stacked, the server would constantly crash to the point only a backup would make it playable. This also happened with normal agricartions are placed down.
http://pastebin.com/fC71QwWd

See if you can reproduce without other mods (especially those coremods), there's almost no reason that crash should be happening in the place it is. Anyways, I'll add some safeguards.

Alright I tested your suggestions and it seems that removing thaumicinfusions caused the first issue but now a new issue? http://pastebin.com/Msh8kFtR

That's (hopefully) solved by the next build (early next week): 071bcef