The error log tells, that the error occurred directly after loading and there is an error with plants. Did you created a new world or load an existing one?
In the first case: could you please send me the seed of the world (options menu -> world options -> world seed),
else could you please send me additional to the seed, the player file, which you'll find in "generated/worlds/<world name, which failed>/player/<player name>.xml" (the content from "<InCave>" until "</LeftHandItem>" would be enough, if you don't want to send the complete file.