Australian competitive compound leaves evergreen tree fast-growing fast-spreading flora flower spikes flowers invasive native native flora native plant ornamental plant prolific prolific seeder Queensland native red spikes schefflera actinophylla spikes terminal inflorescence tree umbrella tree unique flowers abstract appearance background color colored colors colour coloured colours compound-leaves connected evergreen-tree foliage green greenery leafy leaves native-flora native-plant prolific-seeder Queensland-native schefflera-actinophylla umbrella-tree