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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 · Pearl Hill 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 ellipticum

Hypericum mutilum
You are here
Hypericum perforatum
Common Name

Pale St. John’s-wort

Dwarf St. John’s-wort

St. John’s Wort
Plant 8-20" (20-50 cm) tall. Stems are hairless, somewhat 4-angled.< 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 Yellow, in clusters of 1 to a few at stem and branch tips. Each flower is ⅜-½" (1-1.4 cm) around, with 5 yellow petals and 5 pale green sepals, a fountain of yellow stamens, and three styles fused into one in the center. (Rarely, the number of sepals and petals may be 4 or 6.) There are in excess of 100 stamens. Flowers appear from July to August. 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 ⅜-1½" (1-4 cm) × ⅛-¾" (3-20 mm), and elliptical-oblong in shape, generally rounded at leaf tips, and attached directly to the stem (sessile). 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 Capsules are ⅛-³/₁₆" (4-6 mm) × ⅛-³/₁₆" (3.5-5 mm), ellipsoid, and rounded to a tip. 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 Wild
Occurrence     Common, sometimes invasive

 

 
Hypericum punctatum
Common Name

Spotted St. John’s-wort
Plant 5-41" (13-105 cm) tall, with hairless red or green stems.
Flowers Yellow, 5-petaled flowers, densely clustered at stem tips, are ¼-½" (8-15 mm) around. Sepals are also dotted with rows of black dots. At the center of each flower is a round central ovary, from which 3 styles extend. The tip of each style is often red. Surrounding this are more than 13 stamens. Flowers appear from May to Sep.
Leaves Leaves are unlobed, hairless, opposite, oblong to oval elliptic, ¾-2" (1.9-5.7 cm) long × ¼-½" (8.3-12 mm) wide. New leaves are spotted with tiny black glands. They are typically widest somewhat past the midpoint. Leaves are usually attached to the stem (sessile).
Fruit Upright, ovoid or teardrop-shaped capsule ⅛-¼" (4-6.3 mm) long, reddish to deep purple.
Range/ Zones

Type Wild

 

Online References:

Hypericum perforatum on Missouriplants.com

Hypericum perforatum on Wikipedia

Hypericum perforatum on www.mayoclinic.org

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)

7/2/2015 · Bemis Rd., Pepperell, MA
≈ 4½ × 4" (11 × 10 cm)

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

7/17/2019 · Oceanview, Falmouth, ME
≈ 2½ × 2½" (7 × 6.9 cm)

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

6/24/2015 · Nashua River Rail Trail, 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, 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)

7/17/2019 · Oceanview, Falmouth, ME
≈ 6 × 4" (14 × 10 cm)

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

6/16/2010 · Nashua River Rail Trail, 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)

7/2/2015 · Bemis Rd., Pepperell, MA
≈ 4 × 6" (10 × 16 cm)

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

6/28/2017 · Andres Art Institute, Big Bear Mountain, Brookline, NH
≈ 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)

7/17/2019 · Oceanview, Falmouth, ME
≈ 3 × 2½" (8.1 × 6.3 cm)

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

7/2/2015 · Bemis Rd., Pepperell, MA
≈ 7 × 4½" (18 × 12 cm)

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

7/2/2015 · Bemis Rd., Pepperell, MA
≈ 22 × 20" (57 × 50 cm)

Hypericum perforatum description by Thomas H. Kent, last updated 20 Jul 2019.

© FloraFinder.org. All rights reserved.


 

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

7/28/2013 · Andres Institute of Art, 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)

7/17/2019 · Oceanview, Falmouth, ME
≈ 3½ × 5" (8.6 × 12 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, MA
≈ 3 × 2" (8.2 × 5.8 cm)

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

7/17/2019 · Oceanview, Falmouth, ME
≈ 2½ × 3½" (6.9 × 8.6 cm)

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

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

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

7/2/2015 · Bemis Rd., Pepperell, MA
≈ 8 × 5" (19 × 12 cm)

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

7/28/2013 · Andres Institute of Art, 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, MA
≈ 10 × 7" (25 × 16 cm)

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

7/17/2019 · Oceanview, Falmouth, ME
≈ 4 × 3" (10 × 8.4 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, 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)

7/2/2015 · Bemis Rd., Pepperell, MA
≈ 7 × 4½" (16 × 11 cm)

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

6/16/2010 · Nashua River Rail Trail, 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, Brookline, NH
≈ 10 × 7" (25 × 16 cm)

Range:

About this map...