Answer: Hummingbirds are attracted to Albizia (silk tree), Citrus, Erythrina (coral tree), and Chilopsis (desert willow). All but the citrus tree will produce some litter from falling petals, and all will cast shade. Of the above, silk trees drop the most litter. Citrus trees will provide the added bonus of fruit so your final decision will probably include some kind of a trade off if you want flowers to attract wildlife but not much in the way of spent flowers or falling berries! Adult butterflies swarm to shrubs such Abelia, Buddleia, Ceanothus, Lavandula and Lilac, but do not generally frequent trees. Good luck with your new tree!
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