Jeff,

Unless I am mistaken, there are only two "main" BOP plants within the Strelitzia genus. This would be Giant or White (GBOP/WBOP/GWBOP) and Orange (OBOP or just BOP). There is some technical variation... for intance: there are two major species of Giant White BOPs (Strelitzia Nicolia and Strelitzia Alba) but they look more or less the same to the average person. I believe the only real difference is the blooming time. So really, unless you want to get into minutia there is only so far you can go if you've gone bird crazy. ;)

Then there is also the genus Caesalpinia which is also referred to as BOPs and sometimes called the Mexican BOP which would include orange and yellow varieties as well as some others. I personally consider the use of BOP here as a misnomer as BOPs have always referred to Strelitzia to me but that is JMO.

A few other things to take note of:

1) While Strelitzia is often referred to as having "banana-like" leaves, they are not bananas. They are neither in the genus Musa or Ensete or even in the family Musaceae for that matter.

2) If you are heavily interested in Strelitzias you may also want to take a look at Bananas (Musa and Ensete) as well as the Traveller's Palm (Ravenala madagascariensis) which is about as close to a BOP as you can get outside of Strelitzia. Personally, my interests in BOPs bridged to TPs and finallly to Musa and then Ensetes so you may want to take a look at all of those if BOPs interest you.

Laurence