Woodland agrimony is the smallest member of the Agrimonia genus in New York. The species name means "little beak" and refers to the small point on the top of the fruit formed by the mature sepals.
There are currently 17 known populations in the state but almost all of the populations have less than 100 plants. There is only one large population of more than 10,000 plants. There are 16 historical populations, mostly from the lower Hudson Valley and Long Island, but many of them have become extirpated by development. Population trends seem to be stable and threats to known populations are low.
There have been very few follow-up surveys of the occurrences in the state but the few that have been done show no change in status.
The plant populations will probably be stable for the foreseeable future but more surveys are needed. Most populations occur in areas where habitat development is slow.
More research is needed before a full threats assessment can be addressed. At this time, the threats are presumed minimal. The main threats are probably habitat conversion due to logging, development, and succession. Deer browse and invasive species may present local threats to some populations.
The woodland understory where this species occurs should be left undisturbed. A sufficient forest buffer should remain around populations to prevent the introduction of exotic species or a change in natural processes.
More specific information is needed about habitat preference for this species.
A plant of rich mesic forests, forested gorge slopes cutting through calcareous bedrock, streambanks in rich forests, forested slopes adjacent to streams, forested limestone benches, dry oak woods, wooded pastures on rich soil, shrub thickets, and other mesic sites that are typically wooded and on calcareous soils (New York Natural Heritage Program 2006). Woods, fields, and thickets (Rhoads and Block 2000). Moist rich woods (Gleason and Cronquist 1991). Oak-hickory woods, sandy clearings, and thickets (Voss 1985). Open woods (Fernald 1970).
Typically a plant of calcareous regions, this plant ranges from Albany, west along the Niagara/Onondaga Escarpment, and south in Letchworth State Park, the Hudson Valley, and Long Island.
This herbaceous plant ranges from Connecticut, New York, Michigan, and Minnesota, south to Texas and Florida.
Woodland Agrimonia leaves grow on slender stems up to 3 feet tall but they are usually 2 feet tall or less. Each leaf contains 3-9 leaflets which are thin and oblong with large coarse teeth. They have conspicuous glands on the underside but are otherwise without hairs or with short hairs on the veins beneath. The flowering and fruiting stem has glands on the surface and sometimes also a few straight bristles. The bottom half of the bell-shaped fruit is about 1/4" long and covered with glands but not hairy. The roots are sometimes tuberous and thickened but not fibrous.
This slender plant with nearly glabrous stems grows up to one meter tall. The stems are up to 3 mm thick and the roots are sometimes tuberous-thickened. The 5-7 larger leaflets are elliptic to narrowly obovate, glabrous or with few hairs along the veins, and with small resinous glands beneath. There are 1-3 smaller leaflets between each pair of larger leaflets. The axis of the inflorescence is glandular. The yellow flowers are 4-5 mm wide and the floral tube 2-2.5 mm wide. The fruits are 3.5-9 mm long.
The plant should be in flower or in fruit with leaves. To verify its identification, collect a voucher specimen that includes the entire plant (i.e. leaves, roots, flowers, and fruits).
Common agrimony (Agrimonia gryposepala) has glands and long speading hairs in the flowering axis. In addition, the stem in the common agrimony is up to 4 mm thick and the fruit has many more bristles.
This plant begins to flower by late June and fruits are present from late July to early frost. This plant can be identified vegetatively, but ideally identifications use flower and fruit characteristics. As such, surveys are best conducted from early July to mid-September.
The time of year you would expect to find Woodland Agrimony vegetative, flowering, and fruiting in New York.
Agrimonia rostellata Wallr.
Voss, E.G. 1985. Michigan Flora. Part II. Dicots (Saururaceae - Cornaceae). Cranbrook Institute of Science and University of Michigan Herbarium. Ann Arbor, Michigan. 724 pp.
Fernald, M.L. 1950. Gray's manual of botany. 8th edition. D. Van Nostrand, New York. 1632 pp.
Gleason, Henry A. and A. Cronquist. 1991. Manual of Vascular Plants of Northeastern United States and Adjacent Canada. The New York Botanical Garden, Bronx, New York. 910 pp.
Holmgren, Noel. 1998. The Illustrated Companion to Gleason and Cronquist's Manual. Illustrations of the Vascular Plants of Northeastern United States and Adjacent Canada. The New York Botanical Garden, Bronx, New York.
Mitchell, Richard S. and Gordon C. Tucker. 1997. Revised Checklist of New York State Plants. Contributions to a Flora of New York State. Checklist IV. Bulletin No. 490. New York State Museum. Albany, NY. 400 pp.
New York Natural Heritage Program. 2010. Biotics database. New York Natural Heritage Program. New York State Department of Environmental Conservation. Albany, NY.
New York Natural Heritage Program. 2020. New York Natural Heritage Program Databases. Albany, NY.
Newcomb, Lawrence. 1977. Newcomb's Wildflower Guide: An Ingenious New Key System for Quick, Positive Field Identification of the Wildflowers, Flowering Shrubs, and Vines of Northeastern and North-Central North America. Little, Brown and Company. Boston.
Rhoads, Ann F. and Timothy A. Block. 2000. The Plants of Pennsylvania, an Illustrated Manual. University of Pennsylvania Press, Philadelphia, PA.
Weldy, T. and D. Werier. 2010. New York flora atlas. [S.M. Landry, K.N. Campbell, and L.D. Mabe (original application development), Florida Center for Community Design and Research http://www.fccdr.usf.edu/. University of South Florida http://www.usf.edu/]. New York Flora Association http://newyork.plantatlas.usf.edu/, Albany, New York
Weldy, Troy W. and David Werier. 2005. New York Flora Atlas. [S.M. Landry, K.N. Campbell, and L.D. Mabe (original application development), Florida Center for Community Design and Research. University of South Florida]. New York Flora Association, Albany, NY. Available on the web at (http://newyork.plantatlas.usf.edu/).
Information for this guide was last updated on: January 12, 2009
Please cite this page as:
New York Natural Heritage Program. 2020. Online Conservation Guide for Agrimonia rostellata. Available from: https://guides.nynhp.org/woodland-agrimony/. Accessed January 25, 2020.