Nomenclature - What is a Species?
Rhododendron ABC's #1
Almost every endeavor that involves collection, study, nature and classification of things, inanimate or animate, results in the accumulation of descriptive words. These words, in the course of time, become a sub-language or, jargon known perfectly well by persons engaged in the various endeavors. To newcomers who encounter the jargon, the descriptive words are foreign and may even be "turn-offs" that cause the novice enthusiasts to lose interest and feel inferior to more experienced and veteran enthusiasts.
So it is with our favorite subject, Rhododendrons. Of the many jargon words we use when discussing our favorite plants, probably no word is used more often than species. This is a relatively simple word that appears to be plural, but which can be used with a singular or plural meaning. So it is somewhat unique. Ask any enthusiast what is a species, and the person will know immediately what you are asking. But it turns out that it is not really easy to come up with a precise and concise definition. One thing to remember is that the word is always seemingly plural. Specie has an entirely different meaning, literally, the "coin of the realm".
So just what does the word species imply? In the botanical world, we can say that a species is a group of plants naturally occurring in the wild, that includes individual plants which are so nearly alike in their main characteristics that they all might have come from the same seed parent. Indeed, the main test to determine if a plant is a species is to cross it either with itself or with another plant in the same group and see if the offspring are like the parents, similar to each other, or if they diverge from each other in significant traits. Thus we can see that species is an arbitrary term used to indicate close relationship and that it really represents a primary 'blood' relationship and is regarded as the unit of classification of all plants; a group of species is a genus and a group of genera is a family.
One of the charms of the study of rhododendrons is to cultivate species collected from many diverse areas and try to grow them to the flowering stage. To our everlasting satisfaction, rhododendron species, in contrast to many other plant species, freely interbreed with numbers of other rhododendron species and can produce swarms of fertile individuals with differing characteristics and are called hybrids. This greatly expands the number of possible types. The number of possible hybrids is almost limitless.
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