code: def _grow_trees(self):
          
          if self.grow_method == GROW_AUTO_INCREMENTAL:
              self.tree_kwargs['auto_grow'] = True
          
          while len(self.trees) < self.size:
              self.trees.append(Tree(data=self.data, **self.tree_kwargs))
docs: Adds new trees to the forest according to the specified growth method.