Class: Magnoliopsida Subclass: Rosidae Order: Rhamnales
Family: Rhamnaceae
Host Plant for Endangered Species,
Erynnis martialis Mottled Duskywing butterfly

Buckthorn Family, Rhamnaceae:
Worldwide, there are 58 genera and 900 species in the Buckthorn family. Members are dicotyledon shrubs or small trees, sometimes with thorns, with simple leaves that are usually serrated. Their arrangement may be alternate or opposite. Flower clusters give the impression of foamy, white, greenish or bluish sprays. With respect to sepals, petals, and stamen, the flowers present in 4-5 parts. They are usually bisexual. Stamens are opposite to the petals and alternate with the sepals. The usual 3 styles indicate 3 partition ovary walls, forming 3 chambers. The yield is in the form of capsules or berries visibly divided into three parts.
Genus, Ceanothus:
Members of genus, Ceanothus, include buckbrush, ceanothus and red root. In Thomas J. Elpel’s Botany in a Day, C. americanus (New Jersey Tea) is indicated as having many utilitarian and medicinal uses. He describes it as beneficial to “healthy people under stress”, but not a heroic herb for treating the sick.
Alternate Names:
Jersey tea ceanothus, red root (red-root, redroot), mountain sweet (mountain-sweet; mountainsweet), and wild snowball.
Description/Features:
This shrubby perennial stands 30.5 – 92 cm (1-3 ft) high. The stems are herbaceous, extending up from a woody, gnarled rootstock. These die back to near soil level each year. The woody portion reaches deep into the ground via a thick root system that gets quite large in the wild. Extending from this are fibrous hairs that grow close to the earth’s surface. All of these features add up to a highly drought-resistant and fire-tolerant species. Also worthy of note, as a plant that fixes nitrogen due to symbiosis with bacteria, it adds health to the soil.
The stems are covered in both short curly and long straight hairs. Petioles (leaf stalks) and the underside of leaves are pubescent (covered in soft hairs).
This plant has an alternate leaf arrangement. The leaves are petiolate (having a leaf stalk) and ovate to lanceolate (egg-shaped to lance-shaped), with serrate (saw-toothed) margins. The margin “teeth” are each tipped with a gland (an organ producing a secretion) that appears as a black or red dot. Highly useful for identification are the two prominent veins extending from the base of the leaf, arch along the midrib and end mid-leaf at its margin.
Range:
New Jersey tea is native to Eastern North America and, in Canada, is found in Ontario and Quebec.
Habitat:
This plant, host to Erynnis martialis (Mottled Duskywing) butterfly prefers a dry habitat with sparse vegetation. In Ontario, this may be open barrens, sandy patches in woodlands, the rare ecosystems of Ontario – oak woodlands, pin woodlands, tallgrass prairies, and alvars. Alvars are limestone areas with shallow dry soil (clay or sandy), having sparse vegetation of early successional grass, shrub and wildflower species. More common places it may grow are roadsides, hydro corridors, river banks, and shady hillsides. It is not tolerant of closed canopies. C. americanus is an Ontario tallgrass prairie indicator species.
Note: Karner blue, frosted elfin and eastern Persium duskywings depend upon similar habitats as Mottled Duskywing, but are mostly gone from Ontario and Canada at large.
Similar Plant:
Also of the Buckthorn Family and native to Eastern North America is Ceanothus herbaceus Prairie Redroot. It is quite similar in appearance to C. americanus, but presents smaller, more narrowly elliptic leaves. Prairie Redroot is quite rare in southern Ontario.
Reproduction:
Flowers grow in cylindrical clusters known as “thyrse”, a mixed inflorescence in which the main axis is indeterminate (outer or lower flowers open first while the stem continues to grow) and the secondary and ultimate axes are determinate (terminal flowers open first to prevent further growth of the stem or branch). They are both axillary (spring from the axil, the angle formed by the upper side of a leaf and the stem) and terminal (spring from the apex or tip of the plant).
Each individual flower is a white, fragrant, cup-like floral tube with 5 hooded petals, each clasping an anther when in bud.
Each fruit of C. americanus is a 3-lobed capsule-like “dehiscent drupe”. This is a fleshy fruit containing seeds enclosed in a stony covering that, when mature, opens naturally in such a way so as to explosively eject the seeds.
Ecology/Associations:
In Ontario, Mottled Duskywing (Erynnis martialis) butterfly relies exclusively on C. americanus (New Jersey Tea) for all of its life cycle needs, including oviposition (egg laying), larval sheltering and feeding, and adult nectaring and basking. White-tailed Deer and rabbits eat the in-season twigs. Wild Turkey and Bobwhite Quail, both ground-foraging birds, consume the seeds.
Uses:
C. americanus is commonly called Red Root or Red Shank by those who use it as a medicinal plant. The red roots and root bark was/is used by Indigenous peoples to treat, among other things, upper respiratory tract infection. Modern herbalists use the root bark to treat problems of the lymph system. Making dye is one utilitarian use for root and flower extracts. The more recent common name, New Jersey Tea, comes from human use during the Revolutionary War. Though it does not contain caffeine, it was used as a substitute for imported tea after the Boston Tea Party of December 16, 1773.
Threats:
The main and most direct threat to C. americanus is destruction of its habitat, including habitat fragmentation, due to various forms of human development. These include changes by design, such as the planting of jack pine; pesticide use, including spraying for gypsy moth control; flooding; and, introduction of invasive species, such as Dog Strangling Vine.
Less significant, yet still threatening, are natural habitat changes resulting from natural succession, canopy closure and deer browsing.
Disturbance Management:
To the contrary, fire, both natural and controlled burns, serve to maintain suitable habitat conditions. With such brilliant adaptations for surviving naturally-occurring fires – deep, burly root system and yearly die-off of above-ground stems – the burning off of woody plants clears the way and opens the canopy for fire-tolerant, drought-resistant New Jersey Tea.
Note, with reference to the threats and management above: All of these threats are real and present dangers to Mottled Duskywing, the butterfly species that depends entirely on this plant for its survival. While fire can cause direct mortality to individual butterflies, timely disturbances of this nature maintain suitable habitat conditions for future generations.
A Final Note: E. martialis (Mottled Duskywing) was once plentiful in the Pinery Provincial Park. Through preservation of the Pinery’s existing oak savanna, The Ontario Butterfly Species at Risk Recovery Team hopes to reintroduce and ultimately establish a self-sustaining population of this endangered butterfly.
To learn more about:
- the Mottled Duskywing recovery project, please follow OBSARRT
- Erynnis martialis butterfly, please follow Mottled Duskywing
- species at risk recovery, in general, and how to be a good steward, please follow “About Species at Risk Recovery in Ontario”
Bibliography:
Elpel, Thomas J. Botany in a Day The Patterns Method of Plant Identification. Pony, Montana: HOPS
Press, LLC, 1996.
Hickey, Michael and Clive King. The Cambridge Illustrated Glossary of Botanical Terms. Cambridge,
United Kingdom: Cambridge University Press, 2000.
Linton, Jessica. 2015. Recovery Strategy for the Mottled Duskywing (Erynnis martialis) in Ontario. Ontario Recovery Strategy Series. Prepared for the Ontario Ministry of Natural Resources and Forestry, Peterborough, Ontario. v + 39 pp.
On-line Resources:
“2019 Wildflower of the Year: New Jersey Tea (Ceanothus americanus).” Hayden, W. John. Virginia
Native Plant Society (VNPS Communications), 6 Feb 2019. Web. Accessed 30 Mar 2020. https://vnps.org/2019-wildflower-of-the-year-new-jersey-tea-ceanothus-americanus/.
“Butterflies of Canada – Mottled Duskywing (Erynnis martialis) (Scudder, 1869).” Layberry, Ross A., Peter W. Hall, and J. Donald Lafontaine. Canadian Biodiversity Information Facility (CBIF). Government of Canada, 2002. Updated 09 July 2014. Web. Accessed 17 Mar 2020. https://cbif.gc.ca/eng/species-bank/butterflies-of-canada/mottled-duskywing/?id=1370403265694.
“Ceanothus americanus.” Alabama Plant Atlas, Alabama Herbarium Consortium & The University of West Alabama, 2020. Web. Accessed 17 Mar 2020. http://www.floraofalabama.org/Plant.aspx?id=3093.
“Ceanothus americanus L. New Jersey redroot, New Jersey tea.” Native Plant Trust GO BOTANY. Web. Accessed 30 Mar 2020. https://gobotany.nativeplanttrust.org/species/ceanothus/americanus/.
“Ceanothus americanus.” Wikipedia. Updated 02 Dec 2019. Web. Accessed 30 Mar 2020. https://en.wikipedia.org/wiki/Ceanothus_americanus.
“Family Hesperiidae.” Layberry, Ross A., Peter W. Hall, and J. Donald Lafontaine. Canadian Biodiversity Information Facility (CBIF). Government of Canada, 2002. Updated 05 June 2013. Web. Accessed 17 Mar 2020. https://cbif.gc.ca/eng/species-bank/butterflies-of-canada/taxonomic-index/family-hesperiidae/?id=1370403265507.
“Mottled Duskywing Erynnis martialis.” Alabama Butterfly Atlas, USF Water Institute, University of South Florida, 2020. Web. Accessed 17 Mar 2020. https://alabama.butterflyatlas.usf.edu/species/details/59/mottled-duskywing.
“Mottled Duskywing government response statement.” Ontario.ca, Government of Ontario, 23 March 2016. Updated 08 May 2019. Web. Accessed 17 Mar 2020. https://www.ontario.ca/page/mottled-duskywing-government-response-statement.
“Mottled duskywing Scientific Name: Erynnis martialis.” Ontario.ca, Government of Ontario, 18 July 2014. Updated 10 Dec 2019. Web. Accessed 17 Mar 2020. https://www.ontario.ca/page/mottled-duskywing.
“New Jersey Tea (Ceanothus americanus).” Carolina Nature Trees, Shrubs and Woody Vines of North Carolina. Updated 07 Nov 2015. Accessed 30 Mar 2020. https://www.carolinanature.com/trees/ceam.html.
“New Jersey Tea Ceanothus americanus.” iNaturalist Network. Web. Accessed 17 Mar 2020. https://inaturalist.ca/guide_taxa/542245.