unidentified exotic plants in my backyard!

One thing that is really amazing about northern Tanzanian ecology, is the plant diversity. In one garden you could find giant cactus and succulents, birds of paradise, banana trees, thorny acacias and over sized, climbing philodendrons. In my garden alone, I have starch bananas, lemongrass, cassava, pomegranate, elephant ear and flowering succulents! I picked up a great field guide to East African trees and shrubs, but it's missing a lot on the tropicals you see at the elevation of Arusha or Moshi. It seems to me that you can grow just about anything here, with the right conditions of course. Here's some of the more photogenic flora around my house in Arusha. This is a fantastically symmetrical tree in my front yard that is all over town, makes a great shade tree...I haven't found out what it is yet...

Starch Banana, (musa paradisiaca) Swahili name; Matooke. I did not know, that banana trees are actually considered perennial herbs and the banana itself is a "5-sided berry fruit".

Cute little unidentified flowering, creeping succulent.

large, unidentified leafy-like succulent

AWESOME seriously strong and thorny plant with adorable little dainty, pastel flowers, unknown.

Everyone I ask about these just says "bird of paradise" but I want to know what kind! There are several really amazing, alien looking, hanging bird of paradise flowers around here, all of which were definitely imported as ornamentals. I know they are not indigenous here.

Cassava plant, which, silly enough is a major food staple, but is not in the book. In case you don't know what cassava is, it is a delicious potato-like root that is absolutely amazing if you fry or bake it and eat it with sweet chili sauce! I can't tell if my Pomegranate tree is ornamental or not, I've only seen one fruit and it was tiny and waaaay to tart to eat!! although I tried...

Its tough to find a good book on East African gardening or imported species. Any fellow plant nerds care to identify some of these mysterious exotics, (2 great "african" keywords right there) Please let me know!

Here's a couple of interesting sites I found while trying to look up my plants;

http://plantsarethestrangestpeople.blogspot.com/

http://gomestic.com/gardening/amazingly-unique-garden-plants-from-around-the-world/