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About the Atlas - Introductions


The New York Flora Atlas (Atlas) is an online resource for information including distribution of all the vascular plants that occur in New York State. Information is also available for taxa which have been erroneously reported from New York (excluded taxa). In addition to distribution, the atlas provides information for each taxon about habitat, taxonomy, native/non-native status, synonymy, and more. Images are also being added. Accepted taxa and their distributions are based on vouchered specimens housed at public herbaria.

The Atlas has seen a huge amount of improvement over the years and is currently an extremely dynamic tool used to explore the plant diversity in New York. The data can be queried in many different ways allowing the user to extract exactly the information they desire. Lists of species as well as details about particular species are available and all of the information can be downloaded and/or printed. To round out the Atlas website, direct links to other sites and news and announcements are available. A versatile and flexible tool, the Atlas has become a go-to place for details about the flora of New York.

The current Atlas is in draft form for the distribution of plant taxa, the taxa that are considered accepted and excluded for New York, and other information that is provided for each taxon. We are working toward an up-to-date version but much work is still needed. Comments related to the data are always welcomed. We also welcome feedback as to the design and features of the web site.


Homer H. House who became the second state botanist in 1915 (House 1915), started a “card index system” for all the vascular plants of New York at the New York State Museum (NYSM) in Albany (House 1939). The NYSM card files include information on the distribution of plants in the State and were used in the creation of the Preliminary Vouchered Atlas of New York State Flora (New York Flora Association 1990). The Preliminary Atlas was digitized and the county distribution data was converted into a spreadsheet format by John Kartesz. Some additional specimen data was gathered from herbaria. In 2002, a static online atlas was created which included the data from the Preliminary Atlas as well as these new records (Weldy et. al 2002).

In 2004, funding for the current dynamic atlas (i.e. when new records are added they are reflected in the distribution maps) was obtained from the New York State Biodiversity Research Institute with matching funds contributed by the New York Flora Association. Additional funding from the New York State Biodiversity Research Institute has been used to update the database, website, and data. The current atlas has been enhanced by adding additional information on each taxon in addition to adding to the distribution records. For a more extensive history of the atlas see the "History" section in our "User's Guide".


The taxa that were listed in the preliminary 1990 atlas (New York Flora Association 1990) forms the basis for the current list of taxa. The nomenclature from the preliminary atlas was originally updated based on the USDA Plants Database. Since then, the nomenclature and taxonomy of the list has been revised to reflect the outcome of research available in the literature as well as independent field and herbarium investigations. This information has also led to the inclusion of additional taxa to the list and the exclusion of others.

We have yet to critically examine most of the relevant taxa for New York and therefore the current list is considered preliminary and in a draft stage.

The current atlas relies heavily on the county distribution data from the preliminary New York Flora atlas (New York Flora Association 1990). The rest of the distribution records come directly from herbaria, from individuals who report data of specimens housed at herbaria, in a few cases on reports of specimens in the literature, and from the New York Natural Heritage Program’s records of specimens housed at herbaria. While the current distribution records should all be based on vouchered specimens housed at herbaria some of the data is second hand. Eventually, we hope to eliminate all distribution records that are not directly provided by herbaria. Since, most herbaria have yet or only begun to database their collections it is currently (2009) premature to remove all the second hand record data.

Currently (2009) there are perhaps hundreds of thousands of voucher specimens housed at herbaria which we do not have data for. For this reason, the current distributions shown for taxa should be considered preliminary. In other words, just because a taxon is not listed for a particular county does not mean that there is not a voucher specimen of this taxon from that county housed at a herbarium. In addition, a taxon may occur in a county but no voucher has been collected from this county. As data from herbaria become data-based and incorporated into the atlas it should allow for a clearer picture of the distribution of taxa in New York.

The documented occurrence (i.e. vouchered specimen) of a species in a county is indicated by the shading of that entire county. The entire shading of a county should not be interpreted as a county-wide distribution of a plant, rather that one or more specimens were collected somewhere within that county.

For a more detailed overview of the current atlas see the "Current Atlas" section of our "User's Guide".




Please see our acknowledgements of individuals and institutions on the "Contributors" page.

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