Select Decoration
Select Decoration combines several decorations into one decoration that a Grow can carry. Wire the decorations into its inputs, and assign Select Decoration to the Grows like any other decoration. Each row under Weights goes with one input, in input order, and holds a value or a Map; new rows start at 0. Each piece of the skeleton picks one of the wired decorations at random, weighted by those values, and drops the others. It is in the Tab menu under Natsura > Decorations, but not on the toolbar.
Preview Simulate shows the result on the Simulate it belongs to, and Refresh updates the preview.
Status
Select Decoration is experimental. For choosing between parts on one tree, use traits on the Assembly Decoration.
Seed Points
Seed Points makes the points a Simulate grows a stand or forest from, each carrying a species, an age and a random value the tree can read.
Signal
Signal turns ordinary Houdini geometry into an input the growth graph can read, for growth that responds to its surroundings. A Wrangle does this for you on its extra inputs.