Simplify the following text for a Grade 9 native English-speaking person.
Original: Brachychiton ( Kurrajong , Bottletree ) is a genus of 31 species of trees and large shrubs , native to Australia ( the center of diversity , with 30 species ) , and New Guinea ( one species ) .
Simplified: Brachychiton ( Kurrajong , Bottletree ) is a genus of 31 species of trees and large shrubs .