dwarf Labrador tea

Names and Synonyms

Common Names

• dwarf Labrador tea
• marsh Labrador tea
• narrow-leaved Labrador tea
• northern Labrador tea
• crystal-tea
• marsh-tea
• wild rosemary

Scientific Names

Accepted name

Synonyms

• Ledum maximum
• Ledum palustre f. decumbens
• Ledum decumbens
• Ledum palustre subsp. longifolium
• Rhododendron tomentosum subsp. subarcticum
• Rhododendron palustriforme
• Ledum palustre f. parvifolium
• Ledum palustriforme
• Ledum palustre
• Ledum palustre var. longifolium
• Ledum odoratissimum
• Rhododendron subarcticum
• Ledum palustre var. maximum
• Ledum palustre var. angustum
• Ledum palustre var. dilatatum
• Ledum dilatatum
• Ledum palustre f. denudatum
• Ledum groenlandicum f. denudatum
• Ledum palustre var. decumbens
• Ledum palustre var. angustifolium
• Ledum palustre subsp. decumbens
• Ledum palustre var. minus
• Rhododendron tomentosum subsp. decumbens

Regional and Traditional Names

Sources: Wikidata, Catalogue of Life

Taxonomical Classification

This plant belongs to the kingdom Plantae and is classified under the phylum Streptophyta and the class Equisetopsida. Within the subclass Magnoliidae, it is organized under the order Ericales and the family Ericaceae. Finally, it is identified by the genus Rhododendron.

Sources: The World Checklist of Vascular Plants (WCVP)

Distribution

This plant exhibits a specific distribution across several regions of the European continent. In Northern Europe, its presence is documented in the countries of Finland, Norway, and Sweden. Moving toward the center of the continent, it can also be found within Middle Europe. Specifically, its range includes the mountainous landscapes of Austria. Finally, the species extends its reach into the Czechia-Slovakia region.

Sources: The World Checklist of Vascular Plants (WCVP)

Botanical Identification

Ecology

The ecology of Rhododendron tomeentum is characterized by its specific preference for montane environments, typically thriving within forest ecosystems and hilly terrains. It is often found growing in substrates that include sandy soil, which influences its distribution across diverse landscapes. This species occupies a distinct vertical niche within its environment, with an elevational range that spans from a minimum of 400 m AMSL to a maximum of 1400 m AMSL. On average, the plant is most commonly situated at a mean elevation of approximately 900 m AMSL, where the combination of forest cover and topographical variation provides its optimal growing conditions.

Elevational range max:

1400 m AMSL

Elevational range mean:

900 m AMSL

Elevational range min:

400 m AMSL

Habitat :

forest, hills, sand

Genetics

The genetics of Rhododendron tomentosum are characterized by a diploid chromosomal configuration, with a ploidy level designated as 2n. This diploid state indicates that the species possesses two complete sets of chromosomes within its somatic cells, providing a stable genetic foundation for its complex biochemical profiles. Such genetic stability is fundamental to the inheritance of the secondary metabolites, such as grayanotoxins and various terpenoids, which are essential to its medicinal properties. The genomic structure of this species supports the evolutionary adaptation of its specific phenotypic traits, ensuring the consistent expression of its characteristic morphological and chemical signatures through successive generations.

Ploidy :

2, n

Life history

The life history of Rhododendron tomeentum is characterized by its status as a perennial plant, ensuring its survival across multiple growing seasons. As a chamaephyte, its growth form is defined by buds located close to the soil surface, allowing it to persist through varying environmental conditions. Furthermore, the plant maintains an evergreen deciduousness, retaining its foliage throughout the year to support continuous physiological processes.

Deciduousness :

evergreen

Life form :

chamaephyte

Lifecycle :

perennial

Morphology

The morphology of Rhododendron tomentosum is characterized by its growth form as a woody shrub, functioning as a self-supporting plant that does not require climbing structures. It is a terrestrial species that grows independently, lacking parasitic or epiphytic tendencies. In terms of stature, the plant exhibits a variable height, with individual specimens typically ranging from a minimum of 0.12 m to a maximum of 1.25 m, resulting in an average plant height of approximately 0.54 m. Its shoot orientation is described as prostrate, contributing to its overall structural habit.

Aquatic :

terrestrial

Climber :

self-supporting

Epiphyte :

terrestrial

Growth form :

shrub

Parasite :

independent

Plant height max:

1.25 m

Plant height mean:

0.541666666666667 m

Plant height min:

0.12 m

Shoot orientation :

prostrate

Woodiness :

woody

Physiology

The physiology of Rhododendron tomeentum is characterized by a C3 photosynthetic pathway, which dictates its carbon fixation processes and metabolic efficiency. The leaf morphology exhibits significant variation, with leaf lengths ranging from a minimum of 1 cm to a mean of 2 cm, reaching a maximum of 3 cm. The width of the leaves is comparatively narrow, measuring between a minimum of 0.1 cm and a maximum of 0.3 cm, with an overall mean width of 0.2 cm. Furthermore, the plant demonstrates a mean Specific Leaf Area (SLA) of 105.88 cm²/g, reflecting its leaf density and the structural investment in its photosynthetic tissues.

Leaf length max:

3 cm

Leaf length mean:

2 cm

Leaf length min:

1 cm

Leaf width max:

0.3 cm

Leaf width mean:

0.2 cm

Leaf width min:

0.1 cm

Photosynthetic pathway :

C3

Specific Leaf Area (SLA) mean:

105.88 cm²/g

Reproduction

The reproduction of Rhododendron tomeentum is characterized by a sexual process facilitated by bisexual flowers. The flowering period typically begins in May and concludes in July. The plant utilizes a biotic pollination syndrome, specifically relying on insects to facilitate the transfer of pollen. Self-fertilization is present within the species, ensuring reproductive success under varying environmental conditions. Following pollination, the plant produces fruits that vary in size, with a mean length of 0.375 cm, ranging from a minimum of 0.35 cm to a maximum of 0.4 cm. The seeds produced are extremely lightweight, featuring a mean mass of $1.1 \times 10^{-5}$ g, with values ranging from a minimum of $6 \times 10^{-6}$ g to a maximum of $6 \times 10^{-6}$ g. Dispersal is achieved through an anemochorous syndrome, meaning the seeds are dispersed by the wind.

Dispersal syndrome :

anemochorous

Flowering time :

May

Flowering time :

Jul

Fruit length max:

0.4 cm

Fruit length mean:

0.375 cm

Fruit length min:

0.35 cm

Pollination syndrome :

insect

Pollination syndrome :

biotic

Reproduction sexual :

bisexual

Seed mass max:

6e-06 g

Seed mass mean:

1.1e-05 g

Self fertilization :

present

Sources: Global Inventory of Floras and Traits (GIFT)

Plant Parts

Rhododendron tomentosum has 2 reported plant parts identified across 3 scientific publications and several other databases that are studied for medicinal purposes. The most consistently reported plant part include leaf, stem.

Leaf

1. Journal of ethnopharmacology
2. ACS omega

Stem

1. Antioxidants (Basel, Switzerland)

Chemicals

Rhododendron tomentosum has 19 reported phytochemicals identified across 3 scientific publications and several other databases. The most consistently reported chemicals include 5-Hydroxy-7,4'-dimethoxy-6-methylflavone, ASCARIDOLE, Allo-Aromadendrene, Coumarins, EO.

5-Hydroxy-7,4'-dimethoxy-6-methylflavone

1. Dr. Duke

ASCARIDOLE

1. ACS omega

Allo-Aromadendrene

1. Dr. Duke

Coumarins

1. ACS omega

EO

1. Dr. Duke

Ericolin

1. Dr. Duke

Hyperoside

1. Dr. Duke

Ledol

1. Dr. Duke

MYRCENE

1. Dr. Duke

P-CYMENE

1. ACS omega

Activities

Rhododendron tomentosum has 215 reported activities identified across 3 scientific publications and several other databases. The most consistently reported activities include Analgesic, Anticancer, Antidiabetic, Antioxidant, Antiviral.

Analgesic

1. Dr. Duke
2. Fitoterapia

Anticancer

1. Dr. Duke
2. Fitoterapia

Antidiabetic

1. Dr. Duke
2. Fitoterapia

Antioxidant

1. Dr. Duke
2. Fitoterapia

Antiviral

1. Dr. Duke
2. Fitoterapia

11B-HSD-Inhibitor

1. Dr. Duke

5-Lipoxygenase-Inhibitor

1. Dr. Duke

ACE-Inhibitor

1. Dr. Duke

ATPase-Inhibitor

1. Dr. Duke

Acaricide

1. Dr. Duke

Conditions

Rhododendron tomentosum has 1 reported investigations on conditions identified across 3 scientific publications and several other databases. The most consistently reported conditions include acute myeloid leukemia.

Acute myeloid leukemia

1. Phytotherapy research : PTR

Preparations

Rhododendron tomentosum has 8 reported preparations identified across 3 scientific publications and several other databases. The most consistently reported preparations include decoctions of Rhododendron tomentosum leaves, essential oil, ethanolic extracts, extracts, honey.

Decoctions of rhododendron tomentosum leaves

1. Journal of ethnopharmacology

Essential oil

1. ACS omega

Ethanolic extracts

1. Canadian journal of physiology and pharmacology

Extracts

1. Phytotherapy research : PTR

Honey

1. Journal of applied toxicology : JAT

Insect repellent

1. Journal of ethnobiology and ethnomedicine

Tundra tea

1. Phytotherapy research : PTR

Volatile oil

1. Zhong yao cai = Zhongyaocai = Journal of Chinese medicinal materials