Keith, when you hear us using the term 'wide' such as in 'wide crosses', it means the two being crossed come from Species ancestry that is very distant on the genus Lilium family tree. An example of that would be a Division VI Trumpet with L. henryi ancestry pollinated with a Division I Asiatic with L Davidii ancestry. The more distant the two are, the more difficult it becomes to get offspring by normal means. You may get seed with embryos but at some point the embryonic fluid would in some way be incompatible and the embryo dies and aborts. It is a lilies built-in defense and survival mechanism to keep the species pure. Hence, as you referred to above, embryo rescue is the only viable method, which is time consuming, tedious work.
