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Division Hierarchy

Conifers, like all living things, have been grouped by scientists to better understand their place in the world. Plant taxonomy attempts to identify and classify all plants in relation to all other plants by an acute examination of a plant’s individual characteristics. However, taxonomy is a science that is always in flux as new technologies allow for the examination of plants at microscopic — even molecular — levels.

A plant’s taxonomy leads to a naming system (nomenclature) that can be represented graphically in a tree chart. The nomenclature of botanical specimens is based on a set of rules established by the Swedish botanist Carolus Linnaeus in 1753 and much of his structure is still in place, although, as mentioned, new research fuels constant refinement – sometimes with heated debates among academics in the field of plant taxonomy. To identify a conifer you start with its genus, say Abies, for a fir tree. Genus are divided into species, for example, alba (for its unusually white wood) which now makes the plant name a binomial. Abies alba is the binomial for the European silver fir. (Botanical names are in Latin and always italicized.) Next we come to yet another addition to the plant name, the cultivar, which is always enclosed in single quotation ‘marks’ but not italicized. Sometime in 19th century Germany, an Abies alba spawned a unique columnar-shaped specimen that was given the cultivar name ‘Pyramidalis.’ All descendants that retained its unique shape over the centuries have been called Abies alba ‘Pyramidalis’. When all three levels in the hierarchy are used in the plant’s name it is called a trinomial. A common name for this conifer might be pyramidalis European silver fir although using the botanical nomenclature Abies alba ‘Pyramidalis’ will likely yield more authoritative search results. Depending on their characteristics some conifers may have nomenclature that includes not just genus, species and cultivar but sometimes it might include a hybrid (x), variety (var.), subspecies (subsp.) or form (f.) (See: Nomenclature Quick Guide.) Cultivars are what turn a well adjusted gardener into a conifer collector who often becomes afflicted with ACS (Addicted Conifer Syndrome.) Cultivars are freaks of nature whereby a perfectly well formed plant (a binomial) either develops a branch with characteristics unlike that of its parent or the whole plant begins to morph into something different. If this aberration (called a “sport” or “witch’s broom”) is spotted by a knowledgeable plant person who recognizes it for what it is, they will try to propagate it as was done by the discover of ‘Pyramidalis’. If the plant continues to hold its uncharacteristic form over time, and through several generations, the owner or propagator of the new plant can give it a name and submit it to a body like The Royal Horticultural Society (a process that ACS can facilitate). If accepted, they have a new cultivar which can be patented for 20 years, thereby creating the possibility of revenue for the original propagator or grower, who produces it in quantity for the market. Many ACS members have discovered witch’s brooms that are now being sold in specialty nurseries across the country, as well as overseas. The ACS ConiferBase was designed to facilitate searches by knowledgeable conifer enthusiasts but also as an educational tool to help newcomers understand the hierarchy of conifers, so as to better understand the breadth and depth of this horticultural specialty.

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