Yes, I hybridized bearded iris decades ago before my trees grew up and produced so much shade that they don't flower anymore. A book that is very interesting is a compilation of iris breeding information, theorization and experiments, gathered from round-robin letters. It is mostly, but not entirely, about bearded iris. Wilma Vallette's Iris Culture and Hybridizing for Everyone published in 1962. It is inspiring to see how a group of enthusiastic amateurs could amass so much information. Diane Whitehead Victoria B.C. Canada