Flora of Pennsylvania

with special emphasis on central Pennsylvania

A pictorial and taxonomic database

by Michael Hassler (Bruchsal, Germany)

• The database
• Introduction
• Taxonomy
• Statistics
• Contributors and Supporters
• Photographic equipment
• References

• Suggestions and corrections; picture license requests
• I want to contribute missing pictures to this database
• I have found an unknown plant and would like an i.d.

Introduction

Pennsylvania has a rich flora with about 3000 recorded species in total, of them about 2000 native. Although a modern flora has been published recently (Rhoads & Block, 2000), as well as a distribution atlas (Rhoads & Klein, 1993) and a website with county data there is no comprehensive, reasonably complete picture collection on the internet or elsewhere available.

While working for two years (mid 2004 to mid 2006) in State College in the chemical industry, I have, with the help of numerous collaborators, assembled a collection of about 2000 species in digital pictures, which represent about two thirds of the total amount. Because of my location in central Pennsylvania, the flora of this part of the state is represented much better, with 1500 photographs out of a total of 1800 species.

The PNPS Wildflower Society has generously agreed to accommodate this picture collection on their websites.

The picture size for the database (900 x 1150 pixels maximum) was chosen fairly high, in order to maximize the use of the pictures for identification. Most pictures are between 100 and 300 kbyte in size. We hope that this is acceptable to most internet users with broadband access.

All Pennsylvania species, as listed in the Flora of Pennsylvania, have been listed in the database together with some basic information (synonymy, general distribution in Pennsylvania, county records of central Pennsylvania, red list data, habitats, flowering time, etc.), even if no picture is available yet. We hope that other photographers will contribute and donate pictures, in order to create a most complete reference picture collection for the Pennsylvania flora.

There are undoubtedly quite a few initial errors in this database, therefore we would welcome suggestions and corrections.

Michael Hassler, August 2006

Thanks to

While photographing for this collection, I had the help of numerous experts for the PA flora, who gave me detailed tips how to find plants and joined me for excursions.

Special thanks go to Harry Henderson (State College) and Prof. Larry Klotz (Shippensburg). Without their generous and long-time help this database could not have been as complete as it is today. Harry Henderson could also use data he got over many years from the – too early - deceased George Beatty, probably one of the leading experts for the state flora. Both Harry Henderson and Larry Klotz helped with the determination of a great many difficult specimens, especially numerous sheets of Carex.

Thanks go to the Pennsylvania Native Plant Society, especially Maggie Harlan, and their support by hosting this database on their website.

Much help came also from:

Norm Deno (State College) and the amazing and beautiful wildflower collection in his garden

Frank Fee (State College)

William “Rocky” Gleason (Middletown)

Bob Gruver (State College)

Steve Johnson (Sunbury)

Roger Latham (Rose Valley)

Daniel Laughlin (Flagstaff)

Clark Shiffer (State College)

Prof. Kim Steiner, Kathleen Reeder and Tim Phelps (Arboretum of Penn State University)

Eugene Zielinski (Augusta)

For picture contributions we are grateful to:

Karlheinz Knoch (Botanical Garden of the University of Karlsruhe, Germany)

Carl Luer (Sarasota)

Carol Krautmann Lund (Clemson)

Joachim Rheinheimer (Ludwigshafen, Germany)

Taxonomy

Even after 300 years of research, the taxonomy of the Pennsylvania flora is still somewhat in flux. New latin names and combinations are published on a regular basis.

We have used a latin taxonomy which is as close as possible to the Flora of Pennsylvania (Rhoads & Block 2000). Several groups, especially the Asteraceae, have undergone major revisions in the meantime (most notably the Aster relationship, see Flora of North America, vols. 19-21, published 2006). In those cases the most recent available nomenclature was used. This leads unfortunately to some new latin names, which will hopefully become more familiar to the plant lover over time.

We have therefore listed the synonyms quite detailed and made them searchable, in order to simplify the process of finding a plant.

English trivial names are notoriously fluctuating and unreliable – in some cases every field guide has different ones. We have mostly used the names used in the Flora of Pennsylvania (Rhoads & Block 2000), but have amended and/or modified several names, especially in cases where the Flora of Pennsylvania uses only general names (like “sedge” for a specific Carex species).

Statistics

Here are some statistics for the Flora of Pennsylvania, mostly based on the Flora of Pennsylvania (Rhoads & Block 2000). Some rare adventives, which are listed in the Atlas (Rhoads & Klein 1993) have been omitted and are not listed in the database.

Photographic equipment

Most of the pictures have been taken between 2004 and 2006, using a Sony DSC F828 digital camera, which has a marvelous macro function.

Some older pictures, especially of European aliens and neophytes, have been taken in Europe in the years before, using older equipment like Sony DSC F717 and Sony DSC S75.

A minor percentage, mostly macro photos with high magnification, were taken with Canon D10 and D20 cameras, using a 100 mm Canon macro lens. The author uses this equipment mostly for insect and other animal photography, whereever short focus times are critical.

The pictures were deliberately taken in a relatively dark mode, which avoids overexposure to white and yellow colors (still a major problem in digital photography) and gives more natural colors. Still, the differences between various cameras and flash/non-flash modes are huge.

References

Basic literature:

Rhoads, A. F. & Klein, W. M. (1993): Vascular Flora of Pennsylvania: Annotated Checklist and Atlas (Memoirs of the American Philosophical Society). 636 p. [out of print]

Rhoads, A. F. & Block, T. A. (2000): The Plants of Pennsylvania: An Illustrated Manual. - 1061 p. University of Pennsylvania Press. [out of print, new edition in preparation]

Rhoads, A. F. & Block, T. A. (2004): Trees of Pennsylvania: A Complete Reference Guide. - 407 p. University of Pennsylvania Press.

The most recommended field guides:

Newcomb, L. (1989): Newcombs Wildflower Guide. 13^th ed., 490 p.

Clemants, S. & Gracie, C. (2006): Wildflowers in the Field and Forest: A Field Guide to the Northeastern United States (Jeffrey Glassberg Field Guide Series). Oxford University Press, 480 p.

Petrides, G. A. (1998): A Field Guide to Eastern Trees. (Peterson Field Guides). 2^nd ed., 441 p.

Websites:

Pennsylvania Flora Project website

Flora of North America

Flora of North America website

PLANTS database for all of North America

Connecticut Wildflower Society (picture gallery)

Wildflowers of Western Pennsylvania

Delaware Wildflowers