I see... as i had tried explain in my previous post that all people regarless of sex,color, race, social status,background have the potential of the Buddhahood, or planting the seeds of happiness in their lives and that includes both sentient and non-sentient beings- have the Buddha nature withi themselves. But, plants,animals, trees cannot do practice or to search happiness within their lives. Only Humans can do itself because he has the power to do everything to search for enlightenment or happiness while others do not. But, Based on the Buddhist principle of the Oneness of Life and it's environment, Ten factors and the ten worlds- insentient beings can attain enlightenment. Why? it's because of that principle if one's life is enlightened so is their environment- plants, trees, rivers etc.- can attain enlightenment. If peace and happiness prevails in the hearts of people, nothing could be more the place and the environment we live could also achieve the same.