Rhododendron arboreum, Tree rhododendron

Rhododendron arboreum, commonly known as tree rhododendron is an evergreen shrub or small tree belonging to Ericaceae with a showy display of bright red flowers. The plant is native to the Himalayas from Kashmir eastwards to Nagaland and widely grows in Bhutan, China, India, Myanmar, Nepal, Sri Lanka, Pakistan, and Thailand. Rhododendron arboreum is the national flower of Nepal. In India, it is the state tree of Uttarakhand and the state flower of Himachal Pradesh and Nagaland. Rhododendron is derived from Greek words:  “rhodo” means “rose” and “Dendron” means “tree.”  Its name means “tending to be woody or growing in a tree-like form.” The plant is commonly used in gardens, plantations due to its aesthetic value of attractive flower tree plants.

The plant is often harvested from the wild for local use as a food, medicine and source of materials – the flowers and bark are ingredients of commercial cosmetic preparations. The flowers are sold in local markets and used as offerings in temples. The plant can be used as a pioneer species for restoring native woodland and is often grown as an ornamental in gardens. It plays a major role in traditional remedies for different diseases due to its phytochemical potential. It is widely cultivated in different parts of the world for to its aesthetic, commercial and medicinal values.

Tree Rhododendron Facts

Plant Description

Tree rhododendron is a much-branched, evergreen or deciduous shrubs or small tree with a wide crown that normally grows about 20 m (66 ft.) tall, though more usually 12 m (39 ft.) tall and broad. It has been recorded as reaching heights of up to 66 feet (20 m). This plant holds the Guinness Record for World’s Largest Rhododendron. The tree discovered in 1993 at Mount Japfu in Kohima district of Nagaland, India, holds the Guinness Record for the tallest Rhododendron at 108 ft. measured at the time of discovery which is still growing. The plant is found growing in forests, thickets and slopes. The plant prefers moist but well-drained, leafy, humus-rich, acid pH soil, in dappled shade. The trunk is often much-branched, crooked or gnarled. Bark is reddish-brown, soft and rough, exfoliating in thin flakes.

Leaves

Leaves are stiffly leathery, oblong-lanceolate to oblong-oblanceolate, 10-20 cm long and 3.6 cm wide. Crowded towards the ends of branches, petiole is covered with white scales when young. Upper surface is with more or less deeply impressed veins, lower surface is with a compacted to dense and spongy white to fawn indumentum composed of dendroid hairs, occasionally also with a loose floccose rufous upper layer.

Flowers

Flowers of R. arboreum range in color from a deep scarlet, to red with white markings, pink to white. Bearing up to twenty blossoms in a single truss this rhododendron is a spectacular sight when in full bloom. It is reported that the bright red forms of this rhododendron are generally found at the lower elevations. Flowers are showy, red in dense globose cymes. Calyx- fine cleft, Corolla-tube spotted funnel-shaped, Stamens-homozygous declining, Filaments are filiform, Anthers-ovate, and Style is capitate. Flowering normally takes place in between April to May.

Fruit

Fertile flowers are followed by a curved capsule central column composed of fine lobes, longitudinally ribbed; up to 3.8 cm long and 1.25 cm. Seeds are minute, dark brown, compressed, thin linear having an obvolute membrane. Fruiting will occurs on the month of September till October.

Health benefits of Tree rhododendron

Tree rhododendron leaves and flowers have been put to various medicinal purposes traditionally. Latest research has evaluated anti-diabetic, antioxidant, infection?, or irritation, often causing pain?, swelling?, heat, or redness. সহজ বাংলা: শরীরের প্রদাহ; ব্যথা, ফোলা বা লালভাব হতে পারে।" data-rx-term="inflammation" data-rx-definition="Inflammation is the body’s response to injury, infection, or irritation, often causing pain, swelling, heat, or redness. সহজ বাংলা: শরীরের প্রদাহ; ব্যথা, ফোলা বা লালভাব হতে পারে।">inflammation?, pain, or swelling. সহজ বাংলা: প্রদাহ/ফোলা/ব্যথা কমায়।" data-rx-term="anti-inflammatory" data-rx-definition="Anti-inflammatory means reducing inflammation, pain, or swelling. সহজ বাংলা: প্রদাহ/ফোলা/ব্যথা কমায়।">anti-inflammatory?, antimicrobial, heart and liver protective property of Tree rhododendron flower. These and other health benefits of the Tree rhododendron flower is listed below:

1. Acts as an infection?, or irritation, often causing pain?, swelling?, heat, or redness. সহজ বাংলা: শরীরের প্রদাহ; ব্যথা, ফোলা বা লালভাব হতে পারে।" data-rx-term="inflammation" data-rx-definition="Inflammation is the body’s response to injury, infection, or irritation, often causing pain, swelling, heat, or redness. সহজ বাংলা: শরীরের প্রদাহ; ব্যথা, ফোলা বা লালভাব হতে পারে।">inflammation?, pain, or swelling. সহজ বাংলা: প্রদাহ/ফোলা/ব্যথা কমায়।" data-rx-term="anti-inflammatory" data-rx-definition="Anti-inflammatory means reducing inflammation, pain, or swelling. সহজ বাংলা: প্রদাহ/ফোলা/ব্যথা কমায়।">anti-inflammatory?

Various Ayurvedic and homeopathic medicines have used Tree rhododendron flowers and leaves for treating body infection?, or irritation, often causing pain?, swelling?, heat, or redness. সহজ বাংলা: শরীরের প্রদাহ; ব্যথা, ফোলা বা লালভাব হতে পারে।" data-rx-term="inflammation" data-rx-definition="Inflammation is the body’s response to injury, infection, or irritation, often causing pain, swelling, heat, or redness. সহজ বাংলা: শরীরের প্রদাহ; ব্যথা, ফোলা বা লালভাব হতে পারে।">inflammation? and treat gout, rheumatism, bronchitis and stiffness?, or reduced movement. সহজ বাংলা: জয়েন্টের প্রদাহ।" data-rx-term="arthritis" data-rx-definition="Arthritis means joint inflammation causing pain, swelling, stiffness, or reduced movement. সহজ বাংলা: জয়েন্টের প্রদাহ।">arthritis?. Research with Rhododendron arboretum showed important anti-inflammatory? properties. Animal studies showed ability of Tree rhododendron flower extract to cure paw edema? in rats. Flavonoid, tannin, Saponin and other phytochemicals are believed to be responsible for such effect. Two such chemical with strong anti-inflammatory property – Quercetin and Rutin are found in Tree rhododendron flower. Quercetin is known to relieve inflammation of prostate, kidney and urinary bladder. Rutin is helpful in treating painful ulcers in mouth and gastrointestinal tract and used for osteoarthritis?.

2. Pain? killing ability

Young leaves of Tree rhododendron have been traditionally used in treating pain? in the head or upper neck. সহজ বাংলা: মাথাব্যথা।" data-rx-term="headache" data-rx-definition="Headache means pain in the head or upper neck. সহজ বাংলা: মাথাব্যথা।">headache?. Paste made from tree leaves is applied to forehead to relieve head ache. Leaves of Tree rhododendron are astringent and used as poultice in treating wounds and reducing skin infection?, or irritation, often causing pain, swelling?, heat, or redness. সহজ বাংলা: শরীরের প্রদাহ; ব্যথা, ফোলা বা লালভাব হতে পারে।" data-rx-term="inflammation" data-rx-definition="Inflammation is the body’s response to injury, infection, or irritation, often causing pain, swelling, heat, or redness. সহজ বাংলা: শরীরের প্রদাহ; ব্যথা, ফোলা বা লালভাব হতে পারে।">inflammation?. Flower juice is helpful in relieving stomach ache. Animal studies with extract of burans flower and leaves have displayed potential to reduce stimulus of pain in rats.

3. Good antioxidant

Various phytochemicals have been isolated from Burans leaves and flower which have high antioxidant properties. They exhibit beneficial property in getting rid of harmful free radicals in body. Burans flower juice is thus a great antioxidant drink for your heart, liver, kidney and skins. Lab studies confirm antioxidant properties of Tree rhododendron flower and leaf extract and suggest its utilization in therapeutics.

4. Good for diabetes?

Local people from Nepal have been using Tree rhododendron flower for treating diabetes. Latest studies have confirmed anti-diabetic potential of flower and suggested its uses as functional food in treating type I and type II diabetes. Methanol extract of Tree rhododendron flower have showed in-vitro anti-diabetic activity suggesting its potential in development of new medicines for diabetes. Animal studies with flower extract showed reduced blood sugar and cholesterol levels in rats. This property can be attributed to presence of compound hyperin with antioxidant property and ability to inhibit action of certain glucose enzymes.

5. Treat diarrhea

Traditionally flowers and leaves of Tree rhododendron have been used as home remedy over diarrhea and dysentery. Dried petals powder and paste of dried leaves powder are found helpful in relieving diarrhea. Lab studies with ethyl acetate extract of burns flowers showed potential antidiarrheal activity. Similarly animal studies showed effectiveness of Tree rhododendron flower extract in treating castor oil and magnesium sulfate-induced diarrhea in rats. Flower extract showed ability to reduce frequency of stools in rats. Phytochemicals mainly flavonoids, tannins, sterols and reducing sugars were considered responsible for such ability to treat diarrhea.

6. Antimicrobial property

Flowers and leaves of Rhododendron arboretum consist of a wide range of phytochemicals many of which have independently reported antimicrobial properties. These include various bioactive steroids, Saponin and flavonoids. Lab studies with alcoholic extract of the flower have confirmed its effectiveness over wide strains of bacteria in various concentrations. Quercetin and p-coumaric acid are two such flavonoids present in flower with established antimicrobial action. P-coumaric acid is believed to exhibit antibacterial action and help modify gut flora.

7. Good for heart

Tree rhododendron flower juice is good for the heart. It helps in lowering blood pressure and bad cholesterol. Various phytochemicals in flower juice offer antioxidant property and protect heart from oxidative stress and reduces risk of stroke and other heart disorders. Quercetin and rutin are two flavonoid found in Tree rhododendron flower juice which have established its benefits for heart. Quercetin supplementation is prescribed in treating hypertension, atherosclerosis and other heart disorders, while rutin helps in preventing blood clots which pose risk of heart attacks. Drinking Tree rhododendron flower juice is thus good for heart and circulatory system.

Local people consume Tree rhododendron flower when it blooms and is believed to protect them from illness onset a change of weather including allergies, asthma, hives or hay fever. Quercetin in Tree rhododendron flower juice helps preventing allergic response of immune cells in body.

8. Protect liver

Tree rhododendron flower have been used in Ayurvedic medicinal forms to reduce cholesterol and as liver tonic. Animal research showed that alcoholic extract of Tree rhododendron flower and leaves was helpful in preventing liver damage by carbon tetracholoride intoxication. Studies thus confirm the traditional hepato-protective potential of flower. Investigations have attributed antioxidant properties of quercetin related flavonoids, saponins and phenolic compounds in flower and leaves. Tree rhododendron flower juice can also be enjoyed to relieve hangover.

9. Prevention of cancer

Key phytochemicals have been isolated from Tree rhododendron flower which independently have established their ability in preventing cancer. Quercetin and Rutin present in Tree rhododendron flower inhibits growth of cancer cells and reduces risk of cancer. Together with other phytochemicals they offer antioxidant properties which prevent damage of body cells leading to mutation and development of cancer.

10. Beneficial for Skin

Tree rhododendron flower juice is considered beneficial in preventing aging and bringing back skin glow. It is strong antioxidant and offers benefits in preventing damage of skin cells by oxidizing action of sunlight and pollution. It offers anti-inflammatory and anti-bacterial properties to the skin to treat acne, eczema, rashes, and other skin inflammation. Leaves are astringent and poultice; it offers the ability to heal wounds. Drinking its flower juice is good way to enjoy its benefits to your skin. Applying Tree rhododendron juice to your skin can help reduce wrinkles, itching and other skin inflammation.

One can try this homemade face pack using Tree rhododendron flower – Make powder of shade-dried flower. Mix this powder with honey and apply to your face. Leave it for 30 minutes before you wash it with cold water. It will offer glowing, clean skin free of wrinkles.

11. Fight with Respiratory Disease

Using Tree rhododendron is beneficial in treating respiratory diseases. Mix its dried leaves with tobacco, and inhale the smoke from it. It provides relief in respiratory disorders. Taking the powder of leaves of Tree rhododendron flower is also beneficial in respiratory diseases.

Traditional uses and benefits of Tree rhododendron

• Young leaves are made into a paste and then applied to the forehead in the treatment of headaches.
• The juice of the bark is used in the treatment of coughs, diarrhea and dysentery.
• Decoction of the flowers is used to check a tendency to vomit, especially if there is also a loss of appetite.
• The juice of the flowers is used in the treatment of menstrual disorders.
• Petals are eaten to assist the removal of any animal bones that have become stuck in the throat.
• It possesses numerous medicinal properties in the treatment of dysentery, diarrhea, detoxification, inflammation, fever, constipation, bronchitis and asthma.
• Nectar is brewed to make wine and is effective in diarrhea and dysentery.
• Snuff made from the bark of the tree is an excellent cold reliever.
• Juices of petals are good drink for summer and heart tonic.
• Petroleum ether  extract  decreases  the  rate  of heartbeat  and  contraction  in  isolated hearts of
• Wine made from the flowers, known as ‘Guranse’, is commonly drunk in parts of the Himalayas – it is said to be very pleasant and also to be very efficacious in the prevention of altitude sickness.
• The tincture of dried leaves of Rhododendron arboretum has been used in gout & rheumatism.
• Dried flowers are supposedly highly efficacious in checking diarrhea and blood dysentery.
• Fresh and dried corolla that is acid-sweet in nature is given when fish bones get struck in the gullet.
• Flower juice helps in increasing endurance and can be used as a sports drink to enhance performance.
• It is believed that the paste of bark helps in healing the cuts.
• Honey-mixed drink of flowers is used to cure blurry vision and asthma.
• Flower aqueous extract is used as a food coloring agent.
• Dried flowers fried in ghee are used to stop the blood dysentery.
• Crushed flowers are snuffed to stop the nasal bleeding.
• Flower juice is used to cure fever, stomach ache and heart-related problems.
• Dried leaf tincture is used for the treatment of rheumatism and gout.
• Leaves and bark are used to reduce the roughness of the skin.
• Bark juice is used to cure coughs, piles and liver disorders.
• Decoction of the roots is used to cure early stage of cancer.

Culinary Uses

• The tender leaves are used as cooked vegetables.
• Flowers are consumed raw or cooked.
• Flowers are sometimes simply pickled by adding salt and chili.
• In hilly areas, the flowers of Rhododendron arboreum with sweet & sour taste are used in the preparation of squash, jams, jellies, and local brew.
• Fresh petals are used to prepare chutney known as Sarah ki chutney.
• Flower buds are used as a vegetable.
• Local people pick Tree rhododendron’s fresh flowers and make juice, jam, jelly, and chutney out of them.

Other Facts

• It is the national flower of Nepal.
• In India it is the state tree of Uttarakhand and state flower of Nagaland.
• The juice of the leaves is spread over cots and beds to get rid of bed lice.
• Wood is used in turnery, it can also be used to make charcoal and for fuel.
• Wood is much used in Nepal where it is used for making household implements, building small houses and fences.
• Planks of the wood are carved to make boxes, cupboards and other furniture.
• It is a very good fuel, burning well with a long-lasting heat – over collection of the wood for fuel, and also for making charcoal, has become a cause for conservation concern.
• Grained wood is used for making ‘khukri’ handles, packsaddles, gift-boxes, gunstocks and posts.
• Flowers & leaves are fitted in long ropes made of munja grass & tied around the houses including temples as decorations.
• Postal stamp was issued by the Indian Postal Department to commemorate this flower.
• The main stem and branches of the Tree rhododendron are used as fuel wood.
• Tree rhododendron flower is also a part of worship. People offer them in temples while worshiping.
• The tallest Rhododendron arboreum is measured of 108 ft.

Tree rhododendron Chutney (sauce)

Ingredients

• Five-six flowers of Tree rhododendron
• Coriander one bunch
• Mint half a bunch
• Sesame Seeds two tablespoon
• Chopped onions two tablespoon
• Chopped ginger one teaspoon
• Lemon juice two teaspoon
• Salt as per taste
• Honey half tea spoon

Direction

1. Blend Tree rhododendron flowers, fresh coriander, and fresh mint after washing them properly.
2. Toss sesame seeds in a pan over heat and add to the blender.
3. Add chopped onions, ginger and blend to achieve desired consistency of sauce or chutney.
4. Remove to a serving bowl and add salt, lemon juice and honey. Mix well.

Tree rhododendron Paratha (bread)

Ingredients

• Two cups Wheat flour
• Half cup gram flour
• Half a cup chopped Tree rhododendron
• Two tablespoons chopped onion
• One teaspoon chopped fresh coriander
• One teaspoon grated ginger
• Salt as per taste
• Half teaspoon turmeric powder
• Chopped green chilly (Optional)

Directions

1. Sieve the flour and gram flour together and mix together all the ingredients.
2. Add water and knead to till the dough becomes stiff.
3. Make a dough ball of approximately 60 gm. and then roll it out with a rolling pin.
4. Cook it on a flat frying pan, apply ghee and cook till done.
5. Serve with pickle and yogurt.

Precautions

• The leaves are poisonous.
• The flowers can cause intoxication in large quantities.
• High doses may lead to toxicity.
• Flower or its juice may interfere with action of some medications for heart and diabetes.
• Leaves of the Tree rhododendron are toxic, and hence, it requires a proper and precise invention to make this juice available for people to drink for health purposes.

References