Wrong forestry version.
Update to Forestry 4.2 or disable GT Bees in the config.
You re amazing! Know by small log what caused it. 
I read it too and see some bees, but really can't connect it to Forestry! And so fast reaction. Thanks man! 
It solve the problem, but now it messed extrabees, because they crash with NoClassDefFoundError with some of their classes...but that's not your problem
You helped me a lot. Again thx
Toonu
Hello, I tried your newest version of GT5U and even before game starts, game crashed with this error. What can cause it?
cpw.mods.fml.common.LoaderException: java.lang.NoSuchFieldError: instance
at cpw.mods.fml.common.LoadController.transition(LoadController.java:163)
at cpw.mods.fml.common.Loader.initializeMods(Loader.java:744)
at cpw.mods.fml.client.FMLClientHandler.finishMinecraftLoading(FMLClientHandler.java:311)
at net.minecraft.client.Minecraft.func_71384_a(Minecraft.java:552)
at net.minecraft.client.Minecraft.func_99999_d(Minecraft.java:878)
at net.minecraft.client.main.Main.main(SourceFile:148)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at net.minecraft.launchwrapper.Launch.launch(Launch.java:135)
at net.minecraft.launchwrapper.Launch.main(Launch.java:28)
Caused by: java.lang.NoSuchFieldError: instance
at gregtech.loaders.misc.GT_BranchDefinition.getDefaultTemplate(GT_BranchDefinition.java:75)
at gregtech.loaders.misc.GT_BranchDefinition.getTemplate(GT_BranchDefinition.java:96)
at gregtech.loaders.misc.GT_BeeDefinition.init(GT_BeeDefinition.java:710)
at gregtech.loaders.misc.GT_BeeDefinition.initBees(GT_BeeDefinition.java:690)
at gregtech.loaders.misc.GT_Bees.<init>(GT_Bees.java:21)
at gregtech.GT_Mod.onPostLoad(GT_Mod.java:435)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at cpw.mods.fml.common.FMLModContainer.handleModStateEvent(FMLModContainer.java:532)
at sun.reflect.GeneratedMethodAccessor4.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at com.google.common.eventbus.EventSubscriber.handleEvent(EventSubscriber.java:74)
at com.google.common.eventbus.SynchronizedEventSubscriber.handleEvent(SynchronizedEventSubscriber.java:47)
at com.google.common.eventbus.EventBus.dispatch(EventBus.java:322)
at com.google.common.eventbus.EventBus.dispatchQueuedEvents(EventBus.java:304)
at com.google.common.eventbus.EventBus.post(EventBus.java:275)
at cpw.mods.fml.common.LoadController.sendEventToModContainer(LoadController.java:212)
at cpw.mods.fml.common.LoadController.propogateStateMessage(LoadController.java:190)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at com.google.common.eventbus.EventSubscriber.handleEvent(EventSubscriber.java:74)
at com.google.common.eventbus.SynchronizedEventSubscriber.handleEvent(SynchronizedEventSubscriber.java:47)
at com.google.common.eventbus.EventBus.dispatch(EventBus.java:322)
at com.google.common.eventbus.EventBus.dispatchQueuedEvents(EventBus.java:304)
at com.google.common.eventbus.EventBus.post(EventBus.java:275)
at cpw.mods.fml.common.LoadController.distributeStateMessage(LoadController.java:119)
at cpw.mods.fml.common.Loader.initializeMods(Loader.java:742)
... 10 more
Thanks for reply
Toonu
