how do you get the bushes to appear in white forrest in Pokemon white
The appearance of White Forest is dependent on the number of people currently residing there. When the player enters the forest for the very first time, the total number of residents is determined by the number of days it took the player to reach White Forest. The number of residents can be between 0 (low occupancy) and 10 (maximum occupancy). In addition to visual changes, some wild Pokémon will only appear with a certain resident. At maximum occupancy White Forest contains large trees, many patches of tall grass and can have water surfaces. At low level occupancy the trees are smaller, there are fewer or no water surfaces, and patches of tall grass are sparse. The Mayor's House and Pokémon Center are present regardless of how many people reside in the forest.
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Practically in order to get bushes/patches of grass to appear or to have wild Pokemon in it you will need to have residents in White Forest. This can be done easily the faster you get to White Forest. If this wasn't the case then you will have to have an interaction through Entra Link with Black City. This can be done when you and your friend have joint quests through Black City/White Forest. When this is done people and Pokemon will appear. When you have arrived in Black City you will need to battle the residents of the City. The first evoultion of their Pokemon will now appear in the grass pacthes