Castor - Giant Zanzibariensis (Ricinus communis)
Seedling trees, original seeds from Baker Creek (produces seeds prolifically)
Next to morninga, castor is the fastest growing tree I have had experience with in AZ. Whereas morninga gives a sparser canopy that lets a fair amount of light through, castor has huge summer leaves and forms a more dense canopy which creates a lot more shade for the understory trees. Fast growing and beautiful. Huge leaves (dinner plate sized) in summer. Giant Zaniberiensis has a green trunk and green leaves. The flowers attract pollinators like crazy. My castor trees did not defoliate last winter (29 F, winter 2017/2018), so this is also a good choice for someone who wants to shade a tree in summer, but also provide a winter canopy to hold understory heat in.