Randomizing a plant changes its random number seed, which is actually a parameter   [General parameters: Starting seed for random number generator]. The random number seed influences all random choices made as the plant grows, including angles between successive stem segments and branching choices. Two plants with identical parameters except for the random number seed will vary slightly, just enough to look like individual plants. When you randomize plants you basically regrow them with a different random accumulation of chance happenings.

Note: If you increase the value of the parameter [General parameters: Random sway in drawing angles] the impact of randomization will increase. 

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