Rare Species Guide

  Synonyms

Thaspium chapmanii

  Basis for Listing

Thaspium barbinode (hairy-jointed meadow-parsnip) occurs in a number of states in the southeastern and south-central United States, but it becomes rather scarce going north and west. In Minnesota, T. barbinode is known to occur in only a small number of counties in the southern part of the state. Management of forest-dwelling species, like T. barbinode, in southern Minnesota must address several intractable issues. Most of the issues relate to the seemingly unstoppable onslaught of invasive species, which is exacerbated by forest fragmentation.

Because T. barbinode bears a superficial resemblance to other members of the carrot family, it may have been overlooked in past surveys.  Further survey work is needed to clarify the species’ current distribution in the state.  In the meantime, T. barbinode was listed as a special concern species in 2013.

  Description

Thaspium barbinode is a midsize forest herb, reaching a height of about 1 m (3.3 ft.). The stems are hairy at the nodes and loosely branched. The basal leaves have long petioles, and the blades have 2 or 3 major divisions. Each major division is divided into 3 separate leaflets, so each basal leaf would have 6 or 9 individual leaflets. The margins of the leaflets are coarsely and irregularly toothed or cleft. The cauline leaves are similar to the basal leaves but have shorter petioles. The individual flowers are pale yellow or whitish and quite small. They are arranged in a round-topped compound umbel. The fruits are dry, somewhat flattened, with longitudinal ribs.

Thaspium barbinode is very similar to species in the genus Zizia, which are commonly called “golden alexanders”. Perhaps the most visible difference is seen at the nodes on the stem. The nodes of T. barbinode are hairy, those of Zizia are not.

  Habitat

The records of T. barbinode from Minnesota are from mesic hardwood forests in the southern third of the state, primarily on slopes and bluffs bordering river valleys. Most of this type of habitat occurs in southeastern Minnesota, where the Mississippi River and major tributaries create a rugged stream-dissected landscape known as “The Blufflands”. But for unknown reasons, there is only one record of T. barbinode from that region, an 1886 collection from an unspecified location in Winona County. Most of the records are from further west, particularly from the Minnesota River Valley (Minnesota River Prairie Subsection). Some of the states to the south and east of Minnesota report that T. barbinode also occurs in prairies and meadows. So far, all the records from Minnesota are from forests.

  Biology / Life History

Thaspium barbinode is a short-lived perennial that reproduces only by seed. It is described as having an open floral system. This indicates it is accessible to pollination by a great diversity of flying insects, but studies have shown small solitary bees to be the most important pollinators (Lindsey 1984).

Apparently, seeds of T. barbinode are not widely dispersed. Most of the fruits remain attached to the plant, when dead shoots fall to the ground at the end of the growing season (Hawkins 2003). What happens to the seeds then can only be surmised. It is likely that many remain where they fall and survive the winter under the partially decomposed layer of leaves. Others may be carried some distance by small mammals or birds. A study in Kentucky determined that germination of T. barbinode seeds peaked the second year after they were produced, and that some had not germinated until the sixth year (Hawkins et al. 2007).

  Conservation / Management

The key to the conservation of T. barbinode in Minnesota is maintaining healthy and fully functioning forests. In the vernacular of the forest products industry, “healthy forests” usually translates to mean healthy trees, but forests are much more than just the standing trees. Forests are a complex community of interacting and interdependent organisms. In fact, the health of the unseen portion of the community (that which occurs underground) is probably more important to the health of the forest than the portion we can see.

Long term maintenance of a healthy soil biota requires uninterrupted carbon cycling, meaning that fallen trees and branches should be left on the forest floor to decompose. Large openings, such as those created by logging, can cause rapid changes to the habitat by warming and drying the soil, which creates a hostile environment for organisms adapted to the cool and moist conditions of an intact forest. 

Another important, but often neglected, part of the forest community is the insect pollinators. Most of the canopy trees are wind-pollinated, but most of the plants living in the ground layer are insect-pollinated, this includes T. barbinode.

  Best Time to Search

The best time to search for T. barbinode is when well-developed flowers or fruits are normally present. This usually occurs from about the first of June through the end of August.

  Authors/Revisions

Welby Smith (MNDNR), 2018

(Note: all content ©MNDNR)

  References and Additional Information

Hawkins, T. S. 2003. A comparative life history study of six species of Apiaceae of the eastern North American deciduous forests, with particular reference to biomass allocation. Dissertation, University of Kentucky, Lexington, Kentucky.

Hawkins, T. S., J. M. Baskin, and C. C. Baskin. 2007. Seed morphology, germination phenology, and capacity to form a seed bank in six herbaceous layer Apiaceae species of the eastern deciduous forest. Castanea 72(1):8-14.

Kartesz, J. T. 1994. A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. 2 volumes. Second Edition. Timber Press, Portland, Oregon.

Lindsey, A. H. 1984. Reproductive biology of Apiaceae. I. Floral visitors to Thaspium and Zizia and their importance in pollination. American Journal of Botany 71(3):375-387.

Minnesota Department of Natural Resources. 2005. Field guide to the native plant communities of Minnesota: the prairie parkland and tallgrass aspen parklands provinces. Ecological Land Classification Program, Minnesota County Biological Survey, and Natural Heritage and Nongame Research Program. Minnesota Department of Natural Resources, St. Paul, Minnesota. 362 pp.

NatureServe. 2009. NatureServe Explorer: An online encyclopedia of life [web application]. Version 7.1. NatureServe, Arlington, Virginia.

Ownbey, G. B., and T. Morley. 1991. Vascular plants of Minnesota: a checklist and atlas. University of Minnesota Press, Minneapolis. 320 pp.

Wisconsin Department of Natural Resources. 2007. Hairy-jointed Meadow-parsnip (Thaspium barbinode) factsheet. <http://dnr.wi.gov/topic/endangeredresources/Plants.asp>. Accessed 01 July 2009.