Database Field Descriptions
Description of Database Fields
Because this database is very much a work in progress, many fields are empty for many taxa. Fields may be omitted for some taxa, particularly above the species level.
The scientific name of the organism. Taxonomic names consist of two parts. The first part is Latin and essentially consists of a one-word description of the taxon. For species, it's a two-word description because species are conventionally referred to by their "binomial", meaning one word for the genus that a species belongs to and one for the name of the species (its "specific epithet"). Sometimes the Latin name is helpful; Abies grandis, for example, literally translates as "grand fir". Other times, the Latin name merely commemorates a person; Pinus balfouriana, for example, is a pine named after Scots horticulturist John Hutton Balfour. The second part of a taxonomic name is the name of the author(s) who first described that taxon. This is a critical part of the name because the description prepared by that author is literally the definitive description of the taxon. (I say "literally" because some of the old descriptions, especially from the 19th century or before, are notoriously vague.) The naming of taxa is governed by a strict set of rules, the International Code of Nomenclature for Algae, Fungi and Plants. The study of plant classification and its associated nomenclature is called plant systematics; a good library will have some texts on the subject, and a web search will likely turn up class notes from one or another university.
Just as a reminder, here's the hierarchy of taxa, with examples in parentheses:
(Note that names above the rank of genus are not italicized.)
What is a species?
For that matter, what is a genus, what is a family, what is an order? Every plant taxonomist has their own, personal views on these questions, and I expect that every one will also find scientific names on this website with which they disagree. There is disagreement even at the highest levels - how many phyla there are in the Gymnosperms - and the controversy proliferates down the chain from there.
Some of the disagreement occurs because a name was once useful but has become outmoded in the face of new knowledge. Here is an example. There used to be a widely known family of conifers called the Taxodiaceae, that included many famous species such as the redwood, Sequoia sempervirens. Some years ago it was conclusively shown that the Taxodiaceae are polyphyletic, meaning that they are not derived from a single common ancestor, and some of them are more closely related to species in the Cupressaceae than they are to their fellow members of the Taxodiaceae. All of the species formerly assigned to the Taxodiaceae are generally accepted to have closest relatives in the Cupressaceae, so the two families have been merged (there has also been a fair bit of reorganizing within the Cupressaceae). Some people do not know this and continue to talk about the Taxodiaceae, but they are referring to an artificial grouping of plants that has no intrinsic biological significance.
Very often, though, the disagreement between taxonomists occurs because of differing perceptions about what constitutes a species, as opposed to a variety or a genus. It is important to understand that before Darwin, people thought that "species" were literally sacred -- that God had created each species, separate and unique, but had not created varieties or genera or any other taxonomic group; these were simply Man's interpretation of God's work. So, when Darwin said that God didn't create species (he simply accepted that long ago, God created Life [footnote]), he was stating a scientific heresy, and it took about twenty years for most scientists to come around to his way of thinking. After this controversy had simmered down and he penned the final edition of "Origin of Species," he could look back and say
It is quite possible that forms now generally acknowledged to be merely varieties may hereafter be thought worthy of specific names; and in this case scientific and common language will come into accordance. In short, we shall have to treat species in the same manner as those naturalists treat genera, who admit that genera are merely artificial combinations made for convenience. This may not be a cheering prospect; but we shall at least be freed from the vain search for the undiscovered and undiscoverable essence of the term "species."
I agree utterly with Darwin, and so I suggest you simply accept that this Database may not divide species up in quite the same way that other authors do, but that it does try fairly to set forth the great diversity of Gymnosperm life, and that it tries to incorporate the latest scientific knowledge with regard to questions about the origins and commonality of the taxa treated here.
Vernacular names for a taxon, including non-English names where relevant. I try to include representations of names in non-Roman alphabets but this is not always feasible. Chinese names use Pinyin romanization.
A plant may have had a wide variety of scientific names over the years. These past names are called synonyms, and synonyms (abbreviated Syn.) are listed in this field. This field also describes considerations affecting the classification of a species. For example, the Database assigns subspecific classifications to ponderosa pine (Pinus ponderosa) based on information sufficiently new that not all distinct subspecies have yet been formally described. This is an example of the sort of taxonomic assessment I can present in the Database, that you will simply not see in any printed source, because it is an ephemeral situation; after a while, all relevant taxa will have been described and I will amend the Database accordingly. The "taxonomic notes" field also notes known instances of natural hybridization that may locally blur the distinctions between related species.
This field describes what the plant actually looks like. In most cases, this includes the plant's stature, growth form, and characteristics of its foliage and reproductive organs. When I have information on phenology, such as when the cones mature, that is also presented here.
At a minimum, this lists the countries where a taxon is found. For Canada, the U.S., Mexico, and China, it also lists states or provinces. It may also describe climate, soils, major vegetation communities, disturbance regimes, or other ecological matters influencing the distribution of the taxon. In many cases it includes a distribution map.
There are three types of distribution maps, and you will find examples of each in the Database.
The first and most traditional type is one that has been assembled by a dendrologist, often with the help of a cartographer, on the basis of both personal experience and professional knowledge of many different data sources. It is an inclusive map, by which I mean that it includes the entire range of the species, but also includes many locations and habitats where the species does not occur.
The second type is one that consists of locations associated with collections or observations, usually as recorded on herbarium sheets. It is an exclusive map: each data point represents a known occurrence of the species, but the species also occurs in many places not shown on the map. Also, a practical limitation of the map is that many herbarium sheets give location with very low precision. An older collection might simply say "northern California" for example. However, point maps are very useful because they show where the species really can be found, and I prefer them when I'm searching for a particular species, especially if it's a rare one.
The third and best type of map uses point data in conjunction with a knowledge of species climate and habitat requirements along with habitat type maps and climate data. It combines these data to produce a predictive geographic model of where the species is likely to be found. These maps are laborious to produce but have been shown to be highly accurate, sometimes accurately predicting the species' location in places where it has not previously been collected. An example is the map for Pinus monophylla.
I try to present data for both living and historical trees having superlative diameter, wood volume, and height. Most hard data in this field come from the National Register of Big Trees, listing the biggest known tree in the continental USA for all native or naturalized species. There are also some state big tree programs (e.g., the Washington Big Tree Program), and there are a variety of sources for big tree information outside the U.S.; many are listed on the Links page.
I do not present information on where to find these trees. Superlative trees tend to attract attention, and it is usually fatal, either suddenly (as when a tree is cut or burned by someone through accident, malice or mental illness; see Taxodium distichum for an example) or slowly (as its popularity leads to a decline in its root system and increased vulnerability/exposure to disease and injury; see Picea sitchensis for an example). If you care about these trees, it is usually best to leave them alone, except when that means leaving them unprotected from exploitation. See the "Ethnobotany" section of Sequoia sempervirens for a "happy ending" story of such protection, but also note that the locations of both the largest and tallest specimens of that species remain a closely-guarded secret.
Estimated maximum age for a species. If an age is known precisely, relevant details are provided.
Dendrochronology is the study of tree rings. You'd be surprised at the variety of information that can be recovered from tree rings. If you enjoy surprises, try visiting The Ultimate Tree-Ring Web Pages. Information on the dendrochronological uses of a species is either from my personal recollection, or cited from the literature. "The literature" is cataloged on the online Bibliography of Dendrochronology.
Describes use of a taxon by humans. This may include historic use, by native or invasive peoples, as well as modern industrial uses.
Artificial hybrids are rarely included in the database. Neither are cultivars, and for that matter, horticulture is generally given short shrift. My interest in the gymnosperms is as an ecologist, so I prefer to deal with them as wildlife rather than cultivated plants. If you want to buy plants or seeds, or want to know how to grow these plants in your garden, then I suggest you consult gardening books or join a horticultural group such as the American Conifer Society. Incidentally, I also avoid any discussion of amateur medicine, a hot topic with regards to taxa such as Ephedra or Ginkgo.
Tells of especially good places to find the taxon. Usually I try to describe where to find it in habitat, except for certain rare species that may be endangered by irresponsible collection. For these, I try to give examples of exceptionally good specimens in public collections (botanical gardens and arboreta, usually).
Anything of interest that doesn't fit into one of the preceding fields, such as derivation of the Latin name, or importance to wildlife, or its role in history.
Bibliographic citations. Format is fairly standard. Links are provided to sources generally available on the Internet. For dead links, you can often find an archive copy of the page by using the Wayback Machine.
Printed references or links that are not included in the Citations, but will provide useful further information. As the years go by and the level of knowledge about gymnoperms continues its exponential growth, it is ever more difficult for this website to contain even the most important information about every gymnosperm taxon. Nonetheless, I still try to show you where to find that information.
N, S, E, W, C = North, South, East, West, Central. Sometimes I use the abbreviations for states in the U.S. or provinces in Canada, but abbreviations are not used in the "Distribution and Ecology" description in order to simplify the task of searching for all taxa within a particular geographic area. For that, just search for the names of countries (or states/provinces for Canada, the U.S., Mexico, and China).
The site is not available in a mobile version, but because it is formatted for an 800 pixel width, is readable on most smartphones without zooming in.
I've tried to keep all text files to a maximum size limit of 50K and to avoid automatic loading of graphics larger than 10K. Optional graphics, accessed by clicking a thumbnail, may be as big as 110K. Anything over a megabyte, you'll see a file-size indicator. If you want higher-resolution imagery, I have hi-res versions of most of my photos available for commercial use.
Last Modified 2017-11-07