European Cow-Parsnip in Vermont

This is a followup to Hogweeds and Cowparsnips in Vermont. Both Flora Novae Angliae [Haines 2011] and New Flora of Vermont [Gilman 2015] list the same three taxa:

1. Cow-parsnip (Heracleum maximum)
2. Giant Hogweed (Heracleum mantegazzianum)
3. European Cow-Parsnip (Heracleum sphondylium)

This post is about the latter. In its native Europe, Heracleum sphondylium is simply called Hogweed (not to be confused with the infamous Giant Hogweed).

According to Plants of the World Online (POWO), Heracleum sphondylium has 15 subspecies. That begs the question: which subspecies is represented in Vermont? The short answer is: nobody knows! Some authorities claim that Heracleum sphondylium subsp. sibiricum occurs in VT while others claim it is Heracleum sphondylium subsp. sphondylium. Haines observed that plants found in New England seem to have characteristics of both (see the description at the bottom of the page on Heracleum sphondylium at Go Botany). As far as I know, that's where it stands today.

Note: The names Heracleum sphondylium subsp. sibiricum and Heracleum sibiricum are synonyms. Haines and.Gilman recognize the subspecies but POWO (and therefore iNaturalist) accept the latter.

Heracleum sphondylium is locally common in the town of Canaan in the extreme northeast corner of VT. Other than that, it is occasionally found in Essex, Orleans, and Franklin counties. [Gilman 2015] However, no collections have been made in VT since 2009.

There are few observations of Heracleum sphondylium in VT. Its presence has been confirmed along South America Pond Road in Ferdinand. More observations are needed to better understand its current distribution in northern Vermont.

RESOURCES

• Gilman, Arthur V. (2015). New Flora of Vermont. Memoirs of The New York Botanical Garden, Volume 110. Bronx, New York, USA: The New York Botanical Garden Press. ISBN 978-0-89327-516-7.
• Haines, Arthur (2011). New England Wild Flower Society's Flora Novae Angliae: A Manual for the Identification of Native and Naturalized Higher Vascular Plants of New England. Illustrated by Elizabeth Farnsworth and Gordon Morrison. Yale University Press. ISBN 978-0-300-17154-9.
• Heracleum sphondylium (iNaturalist, POWO, Wikipedia)
• Heracleum sibiricum (iNaturalist, POWO, Wikipedia)

• Herbarium specimens:
  ** Along the Maine Central tracks (now the Upper Coos Recreational Rail Trail) in Beecher Falls in the town of Canaan (Essex) (2008246 1968)
  ** Along VT 114, 3.2 km (2 mi) east of the end of Wallace Pond in the town of Canaan (Essex) (566489 1983)
  ** A pullout along VT 102, just south of the village of Canaan (Essex) (1444500 2006)
  ** Large patch along VT 16, south of the village and north of Shadow Lake Road, in Glover (Orleans) (1444498 2008)
  ** Large patch, west side of VT 104, just south of interstate ramp, St Albans (Franklin) (1444497 2009)

Posted on Σεπτέμβριος 05, 2023 0818 ΜΜ by trscavo