great willowherb

Names and Synonyms

Common Names

• great hairy willowherb
• great willowherb
• hairy willowherb

Scientific Names

Accepted name

Synonyms

• Epilobium hirsutum subsp. foliosum
• Epilobium hirsutum var. minus
• Epilobium hirsutum var. glabriusculum
• Epilobium hirsutum var. foliis-variegatis
• Epilobium hirsutum var. villosum
• Epilobium hirsutum subsp. parviflorum
• Epilobium tomentosum
• Chamaenerion grandiflorum
• Chamaenerion hirsutum
• Epilobium mirei
• Epilobium nassirelinulci
• Epilobium himalense
• Epilobium hirsutum var. africanum
• Epilobium hirsutum f. valdepilosum
• Epilobium hirsutum f. alboroseum
• Epilobium hirsutum var. laetum
• Epilobium hirsutum f. minor
• Epilobium hirsutum f. minus
• Epilobium hirsutum var. sericeum
• Epilobium hirsutum var. villosissimum
• Epilobium serratum
• Epilobium aquaticum
• Epilobium amplexicaule
• Epilobium hirsutum var. tomentosum
• Epilobium hirsutum var. subglabrum
• Epilobium hirsutum var. villosissimum

Regional and Traditional Names

Sources: Wikidata, Catalogue of Life

Taxonomical Classification

This plant belongs to the kingdom Plantae and the phylum Streptophyta, falling under the class Equisetopsida and subclass Magnoliidae. Within the order Myrtales, it is classified under the family Onagraceae. Finally, it is categorized within the genus Epilobium.

Sources: The World Checklist of Vascular Plants (WCVP)

Distribution

This plant exhibits a specific distribution pattern across various regions of Northern Europe. It can be found growing naturally within the borders of Denmark. The species also extends its range to include the landscapes of Finland. Additionally, it is documented to inhabit parts of Great Britain and Ireland. Finally, its presence is noted within the territory of Norway.

Sources: The World Checklist of Vascular Plants (WCVP)

Botanical Identification

Ecology

The ecology of Epilobium hirsutum is characterized by its preference for highly moist environments, typically found colonizing rivers and swamps. This species exhibits a broad altitudinal distribution, ranging from sea level (0 m AMSL) up to a maximum elevation of 3200 m AMSL. Throughout its natural range, it maintains a mean elevation of approximately 1250 m AMSL, where it thrives in the saturated soils and riparian zones characteristic of its primary habitats.

Elevational range max:

3200 m AMSL

Elevational range mean:

1250 m AMSL

Elevational range min:

0 m AMSL

Habitat :

rivers, swamps

Life history

The life history of Epilobium hirsutum is characterized by its nature as a perennial plant, allowing it to persist through multiple growing seasons. As a hemicryptophyte, its regenerative buds are located at or just below the soil surface, protected by leaf litter or organic debris during unfavorable periods. The species exhibits a deciduous growth pattern, shedding its foliage seasonally as part of its life cycle.

Deciduousness :

deciduous

Life form :

hemicryptophyte

Lifecycle :

perennial

Morphology

The morphology of Epilobium hirsutum is characterized by its growth form as a non-woody herb and forb, which functions as an independent organism rather than a parasite or epiphyte. It is a terrestrial species that maintains a self-supporting structure, lacking any climbing or vine-like tendencies. The shoots exhibit an erect orientation, supporting a plant height that varies significantly depending on environmental conditions, with minimum measurements recorded at 0.21 m, a mean height of approximately 0.975 m, and a maximum height reaching up to 2.74 m.

Aquatic :

terrestrial

Climber :

self-supporting

Epiphyte :

terrestrial

Growth form :

herb

Growth form :

forb

Parasite :

independent

Plant height max:

2.74 m

Plant height mean:

0.975 m

Plant height min:

0.21 m

Shoot orientation :

erect

Woodiness :

non-woody

Physiology

The physiology of Epilobium hirsutum is characterized by a C3 photosynthetic pathway and a non-carnivorous nutritional strategy. Its leaf morphology demonstrates significant variability, with leaf lengths ranging from a minimum of 4 cm to a maximum of 13 cm, while leaf widths fluctuate between 0.3 cm and 4 cm. The leaves typically exhibit a linear form, maintaining an average leaf size of 28.33 cm². Furthermore, the plant possesses a mean Specific Leaf Area (SLA) of 269.2 cm²/g, reflecting its physiological approach to resource acquisition and leaf mass distribution.

Carnivory :

non-carnivorous

Leaf form :

linear

Leaf length max:

13 cm

Leaf length min:

4 cm

Leaf size mean:

28.33 cm²

Leaf width max:

4 cm

Leaf width min:

0.3 cm

Photosynthetic pathway :

C3

Specific Leaf Area (SLA) mean:

269.2 cm²/g

Reproduction

The reproduction of Epilobium hirsutum is characterized by a sexual reproductive cycle facilitated by biotic pollination. The flowering period typically begins in June and extends through September, featuring pink flowers that range in length from 1.2 cm to 1.8 cm. These flowers utilize a biotic pollination syndrome, specifically attracting insects such as bees to facilitate pollen transfer, and the plant is capable of self-fertilization. Following successful pollination, the plant develops dry, dehiscent fruit in the form of a capsule. These capsules vary in length, with a mean measurement of 5.75 cm, a minimum of 2.5 cm, and a maximum reach of 9 cm. Once mature, the fruit undergoes dehiscence to release its seeds, which are dispersed via an anemochorous (wind-dispersal) syndrome. The seeds themselves are extremely minute, possessing a mean mass of approximately 0.00011195 g (ranging from 0.00005 g to 0.000138 g) and a mean volume of 0.0995 mm³ (ranging from 0.099 mm³ to 0.1 mm³). Notably, asexual reproduction is absent in this species.

Dehiscence :

dehiscent

Dispersal syndrome :

anemochorous

Flower colour :

pink

Flower length max:

1.8 cm

Flower length min:

1.2 cm

Flowering time :

Jun

Flowering time :

Sep

Fruit dryness :

dry

Fruit length max:

9 cm

Fruit length mean:

5.75 cm

Fruit length min:

2.5 cm

Fruit type :

capsule

Pollination syndrome :

insect

Pollination syndrome :

bee

Pollination syndrome :

biotic

Reproduction asexual :

absent

Seed mass max:

0.000138 g

Seed mass mean:

0.00011195 g

Seed mass min:

5e-05 g

Seed volume max:

0.1 mm³

Seed volume mean:

0.0995 mm³

Seed volume min:

0.099 mm³

Self fertilization :

present

Sources: Global Inventory of Floras and Traits (GIFT)

Chemicals

Epilobium hirsutum has 14 reported phytochemicals identified across 0 scientific publications and several other databases. The most consistently reported chemicals include ellagic acid, Flavonoids, Oenothein B, CHLOROGENIC ACID, Ellagitannins.

ellagic acid

1. Natural product communications
2. European journal of drug metabolism and pharmacokinetics
3. Nutrition and cancer

Flavonoids

1. Natural product communications
2. Frontiers in pharmacology

Oenothein B

1. Frontiers in pharmacology
2. Phytomedicine : international journal of phytotherapy and phytopharmacology

CHLOROGENIC ACID

1. Frontiers in pharmacology

Ellagitannins

1. Frontiers in pharmacology

Gallic acid

1. Natural product communications

Hyperoside

1. Frontiers in pharmacology

Isoquercitrin

1. Frontiers in pharmacology

Myricetin 3-O-rhamnoside

1. Phytomedicine : international journal of phytotherapy and phytopharmacology

Oenothein A

1. Frontiers in pharmacology

Activities

Epilobium hirsutum has 1 reported activities identified across 0 scientific publications and several other databases. The most consistently reported activities include Antioxidant.

Antioxidant

1. Phytomedicine : international journal of phytotherapy and phytopharmacology

Medicinal Uses

Epilobium hirsutum has 3 reported medicinal uses identified across 0 scientific publications and several other databases. The most consistently reported uses include SARS-CoV-2, bladder, influenza viruses.

Most Reported Uses

Preparations