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Hypericum perforatum

Hypericum perforatum L.

 

St. John’s Wort, Common St. John’s Wort, Common St. Johnswort

KingdomPlantaePlants, but not fungi, lichens, or algae
SubkingdomTracheobiontaVascular plants—plants with a “circulatory system” for delivering water and nutrients
DivisionMagnoliophytaFlowering plants, also known as angiosperms
ClassMagnoliopsidaDicotyledons—plants with two initial seed leaves
SubclassRosidaeRoses, legumes, proteas, dogwoods, hydrangeas, mistletoes, euphorbias, grapes, many more
OrderMalpighialesA broad group encompassing 16,000 species
FamilyHypericaceaeSt. John’s Wort family
GenusHypericumFrom ancient Greek hyper, “above,” and eikon, “picture,” from an old practice of putting flowers above a picture to ward off evil spirits
Speciesperforatum“Perforated,” for paired leaves joined at the base and “perforated” by the stem

About plant names...

Common St. John’s wort is a native of North America, Europe, Asia Minor, Russia, India, and China.

Identification: Plants are less than 3' (91 cm) in height, and multiply branched. Leaves are oval, opposite, sessile, up to ⅝" (1.8 cm) × ¼" (7 mm), with smooth edges. Flowers are deep yellow, star-shaped, with a central, brushlike spray of stamens. If you look closely, there is a rounded ovary about ⅛" (3.2 mm) in diameter, from which emerge three styles, arranged like the legs of an inverted tripod. They are difficult to see because they are almost the same color and shape as the stamens, but they are longer and thicker. Some species of St. John’s wort have only a single style, so this is an identifying characteristic. Petals have serrated edges and small black dots on the serrations. Flowers are up to ⅞" (2.5 cm) across.

Medical: St. John’s wort is widely used to treat depression, and a number of studies have been performed to assess the efficacy of these treatments. Studies have reported contradictory results, and this has become a contentious issue, in part because pharmaceutical companies stand to lose a very profitable business in other antidepressant drugs. Some studies have concluded that St. John’s wort is more effective than placebo and equally as effective as tricyclic antidepressants, and roughly as effective as serotonin reuptake inhibitors such as Prozac and Zoloft. Other studies suggest no benefits. It is likely that St. John’s wort at least helps with depression.

Below is a comparison of some species of St. John’s wort:

 

Hypericum perforatum (St. John’s Wort, Common St. John’s Wort, Common St. Johnswort)

7/2/2014 · Conservation Area, Shirley St., Groton, MA
≈ 4½ × 7" (11 × 16 cm)

Hypericum perforatum (St. John’s Wort, Common St. John’s Wort, Common St. Johnswort)

7/3/2012 · Yellow Trail from Pearl Hill State Park to Willard Brook State Park, Ashby, MA
≈ 3½ × 2½" (9.6 × 7.2 cm)

Hypericum perforatum (St. John’s Wort, Common St. John’s Wort, Common St. Johnswort)

6/22/2010 · Nashua River Rail Trail, Ayer, MA
≈ 5 × 3½" (13 × 9.2 cm)

 
Hypericum mutilum
You are here
Hypericum perforatum
Common Name

Dwarf St. John’s-wort

St. John’s Wort
Plant 4-18" (10-45 cm) tall, sometimes up to 31" (79 cm), heavily branched, with a shrublike habit. Branches may be 4-angled or smooth, tapering, and sometimes winged. Less than 3' (91 cm) in height.
Flowers ¼" (6.3 mm) in size, yellow or yellow-orange, with five petals and 5-15 stamens. Beneath the petals of each flower there are somtimes green bracts that are narrower but roughly the same length, one for each petal. Blooms from July to October. Bright yellow, star-shaped, with five petals and many yellow stamens about the length of the petals. Petals have serrated edges and small black dots on the serrations. Flowers are up to ⅞" (2.5 cm) across.
Leaves Roughly oval in shape, and attached directly to the stem (sessile). They are opposite, unlobed, ½-1½" (1.3-3.8 cm) long and ¼-¾" (6.3-19 mm) across. Oval, about ⅜" (1.2 cm) long, with smooth edges, occurring in opposing pairs.
Fruit ¹/₁₆-⅛" (2-3.5 mm) in length.  
Range/ Zones

Habitats Sandy forest floodplains, sandy swamps, moist to wed sandy prairies; damp, sandy, acidic areas in general  
Type Wild Wild
Occurrence   Common, sometimes invasive

 

Online References:

Hypericum perforatum on Missouriplants.com

Hypericum perforatum on Wikipedia

Hypericum perforatum on www.mayoclinic.com

Hypericum perforatum on Plants for a Future, a resource and information centre for edible and otherwise useful plants

Hypericum perforatum on Wikimedia Commons

Hypericum perforatum on www.hypericum.com

Hypericum perforatum on the USDA Forest Service's Fire Effects Information Database

Hypericum perforatum on sites.duke.edu (PDF assessing the possible role of St. John’s Wort in the treatment of depression)

Hypericum perforatum (St. John’s Wort, Common St. John’s Wort, Common St. Johnswort)

7/2/2014 · Conservation Area, Shirley St., Groton, MA
≈ 7 × 4½" (16 × 11 cm)

Hypericum perforatum (St. John’s Wort, Common St. John’s Wort, Common St. Johnswort)

6/24/2015 · Nashua River Rail Trail, Groton Ctr, Groton, MA
≈ 4½ × 3" (11 × 7.4 cm)

Hypericum perforatum (St. John’s Wort, Common St. John’s Wort, Common St. Johnswort)

6/24/2015 · Nashua River Rail Trail, Groton Ctr, Groton, MA
≈ 4 × 3½" (10 × 9.6 cm)

Hypericum perforatum (St. John’s Wort, Common St. John’s Wort, Common St. Johnswort)

7/27/2009 · Nashua River Rail Trail, Groton, MA
≈ 5 × 3" (12 × 8.5 cm)

Hypericum perforatum (St. John’s Wort, Common St. John’s Wort, Common St. Johnswort)

6/16/2010 · Nashua River Rail Trail, Groton Center, Groton, MA
≈ 9 × 6" (23 × 15 cm)

Hypericum perforatum (St. John’s Wort, Common St. John’s Wort, Common St. Johnswort)

7/17/2009 · Mt. Lebanon St, Trail, Pepperell, MA
≈ 10 × 7" (26 × 17 cm)

Hypericum perforatum (St. John’s Wort, Common St. John’s Wort, Common St. Johnswort)

6/29/2014 · Mount Agamenticus, York, ME
≈ 9 × 6" (22 × 15 cm)

Hypericum perforatum (St. John’s Wort, Common St. John’s Wort, Common St. Johnswort)

9/3/2009 · Nashua River Rail Trail, Ayer, MA
≈ 4½ × 6" (11 × 14 cm)

Hypericum perforatum (St. John’s Wort, Common St. John’s Wort, Common St. Johnswort)

6/28/2017
≈ 4½ × 3½" (11 × 9.3 cm)

Hypericum perforatum (St. John’s Wort, Common St. John’s Wort, Common St. Johnswort)

8/7/2013 · Amos Kendall Conservation Land, Dunstable, MA
≈ 7 × 5" (18 × 13 cm)

Hypericum perforatum (St. John’s Wort, Common St. John’s Wort, Common St. Johnswort)

7/3/2005 · Pepperell, MA

Hypericum perforatum (St. John’s Wort, Common St. John’s Wort, Common St. Johnswort)

7/17/2009 · Mt. Lebanon St, Trail, Pepperell, MA
≈ 12 × 8" (29 × 19 cm)

Hypericum perforatum description by Thomas H. Kent, last updated 5 Oct 2016.

© FloraFinder.org. All rights reserved.


 

Hypericum perforatum (St. John’s Wort, Common St. John’s Wort, Common St. Johnswort)

7/28/2013 · Andres Institute of Art, Big Bear Mountain, Brookline, NH
≈ 3½ × 4" (9.8 × 10 cm)

Hypericum perforatum (St. John’s Wort, Common St. John’s Wort, Common St. Johnswort)

7/27/2009 · Nashua River Rail Trail, Groton, MA
≈ 5 × 3½" (12 × 9.5 cm)

Hypericum perforatum (St. John’s Wort, Common St. John’s Wort, Common St. Johnswort)

6/29/2014 · Mount Agamenticus, York, ME
≈ 6 × 9" (15 × 22 cm)

Hypericum perforatum (St. John’s Wort, Common St. John’s Wort, Common St. Johnswort)

7/9/2010 · Nashua River Rail Trail, Groton Center, Groton, MA
≈ 3 × 2" (8.2 × 5.8 cm)

Hypericum perforatum (St. John’s Wort, Common St. John’s Wort, Common St. Johnswort)

6/24/2015 · Nashua River Rail Trail, Groton Ctr, Groton, MA
≈ 8 × 6" (20 × 14 cm)

Hypericum perforatum (St. John’s Wort, Common St. John’s Wort, Common St. Johnswort)

7/28/2013 · Andres Institute of Art, Big Bear Mountain, Brookline, NH
≈ 10 × 7" (25 × 16 cm)

Hypericum perforatum (St. John’s Wort, Common St. John’s Wort, Common St. Johnswort)

6/24/2015 · Nashua River Rail Trail, Groton Ctr, Groton, MA
≈ 10 × 7" (25 × 16 cm)

Hypericum perforatum (St. John’s Wort, Common St. John’s Wort, Common St. Johnswort)

Notice the little black dots along the edges of the petals. · 7/21/2013 · Gibbet Hill, Groton, MA
≈ 2½ × 1¾" (6.4 × 4.7 cm)

Hypericum perforatum (St. John’s Wort, Common St. John’s Wort, Common St. Johnswort)

6/21/2010 · Nashua River Rail Trail, Groton Center, Groton, MA
≈ 3½ × 2½" (9.8 × 6.6 cm)

Hypericum perforatum (St. John’s Wort, Common St. John’s Wort, Common St. Johnswort)

7/13/2015 · Mt. Ascutney State Park, Ascutney, VT
≈ 4 × 4" (10 × 10 cm)

Hypericum perforatum (St. John’s Wort, Common St. John’s Wort, Common St. Johnswort)

6/16/2010 · Nashua River Rail Trail, Groton Center, Groton, MA
≈ 4½ × 7" (11 × 17 cm)

Hypericum perforatum (St. John’s Wort, Common St. John’s Wort, Common St. Johnswort)

7/28/2013 · Andres Institute of Art, Big Bear Mountain, Brookline, NH
≈ 10 × 7" (25 × 16 cm)

Range:

About this map...