Recent discussions have made me think about the pronunciation of the scientific names of plants in California. This is a complicated and jam silent pro user guide subject for a great variety of reasons.
Spelling is something that is determined by the International Botanical Congresses which are held every six years, the most recent being the 18th in 2011 in Melbourne, Australia, but this body does not deal with pronunciation. There are two things that are involved here: first, how the names are to be divided into syllables and properly accented, and, second, how the vowels and consonants are to be sounded. Botanical Latin is not classical Latin. That language was derived from the Roman writers of the early first millenium and remained the single internationally-used language of learning throughout Europe until at least the 18th century. Were this not the case, there might well be no uniform international system of botanical nomenclature today. There is therefore little need to utilize strictly-classical Latin pronunciation. Over the years, usage has resulted in certain informal rules of pronunciation, but even these may give way to a person’s own preferences, and are naturally influenced by such things as where he or she grew up, and what pronunciations they were exposed to during their lifetimes.