Pharmacodynamic and ethnomedicinal uses of weed speices in nilgiris , Tamilnadu State , India : A review

Generally, weeds are considered as nuisances in the garden and enemies to the farmer, as there is a misconception that they are useless. Many of the herbs used in Indian traditional medicine and tribal medicine are considered weeds by agriculturists and field botanists (for example, Phyllanthus amarus L., Eclipta alba L., Centella asiatica (L.) etc.). Even though many of these weeds have high ethnopharmacological importance, they are being destroyed and there is a lack of scientific knowledge and guidance. In the Nilgiris many medicinally valuable weeds like Achyranthes bidentata Blume., Artemisia nilagirica Clarke., Centella asiatica L., are very prominent having good therapeutic values like diuretic, antimalarial and brain tonic. The main aim of this review is to expose the important pharmacodynamic and ethnomedicinal values of 50 prominent weeds belongs to 26 different families that grow wild in the Nilgiris. It is possible that some of these weeds could provide an additional income to farmers. There is increasing evidence to support that weeds are relatively high in bioactive molecules thus very important for new drug discovery. Innovative research should be encouraged and scientific workshops conducted by government bodies to communicate the medicinal value of weeds, make weeds economically important and to fill the gap between weeds, farmers and the economy.


INTRODUCTION Weed
A weed may be defined as any plant or vegetation that interferes with the objectives of farming or forestry, such as growing crops, grazing animals or cultivating forest plantations.A weed may also be defined as any plant growing where it is not wanted.For example, a plant may be valuable or useful in a garden, or on a farm or plantationbut if the same plant is growing where it reduces the value of agricultural produce or spoils aesthetic or environmental values, then it is considered a weed.However, some plants are weeds regardless of where they grow.
There are numerous definitions of a weed.Some common definitions include: 1.A plant that is out of place and not intentionally sown 2. A plant that grows where it is not wanted or welcomed 3. A plant whose virtues have not yet been discovered 4. A plant that is competitive, persistent, pernicious, and *Corresponding author.E-mail: chaitanya.phyto@yahoo.com,motmarrilalipop1@gmail.com.
interferes negatively with human activity.No matter which definition is used, weeds are plants whose undesirable qualities outweigh their good points, at least according to humans.Human activities create weed problems since no plant is a weed in nature.Though we may try to manipulate nature for our own good, nature is persistent.Through manipulation, we control certain weeds, while other more serious weeds may thrive due to favorable growing conditions.Weeds are naturally strong competitors, and those weeds that can best compete always tend to dominate.
Both humans and nature are involved in plant-breeding programs.The main difference between the two programs is that humans breed plants for yield, while nature breeds plants for survival.

Characteristics of weeds
There are approximately 250,000 species of plants worldwide; of those, about 3%, or 8,000 species, behave as weeds.Of those 8,000, only 200 to 250 are major problems in worldwide cropping systems.A plant is considered as weed if it has certain characteristics that set it apart from other plant species.
Weeds possess one or more of the following characteristics that allow them to survive and increase in nature: 1. Abundant seed production 2. Rapid population establishment 3. Seed dormancy 4. Long-term survival of buried seed 5. Adaptation for spread 6. Presence of vegetative reproductive structures 7. Ability to occupy sites disturbed by humans

Problems with weeds
Weeds are troublesome in many ways.Primarily, they reduce crop yield by competing for: water, light, soil nutrients, space, CO 2 , reducing crop quality by contaminating the commodity, interfering with harvest, serving as hosts for crop diseases or providing shelter for insects to overwinter, limiting the choice of crop rotation, sequences and cultural practices, producing chemical substances that can be allergins or toxins to humans, animals, or crop plants (allelopathy), producing thorns and woody stems that cause irritations and abrasions to skin, mouths, or hooves of livestock being unsightly, dominant, aggressive, or unattractive obstructing visibility along roadways, interfering with delivery of public utilities (power lines, telephone wires), obstructing the flow of water in water ways, and creating fire hazards, accelerating deterioration of recreational areas, parking lots, buildings and equipment, invading exotic weed species that can displace native species in stabilized natural areas.

Benefits of weeds
Despite the negative impacts of weeds, some plants usually thought of as weeds may actually provide some benefits, such as: Stabilizing and adding organic matter to soils, providing habitat and feed for wildlife, providing nectar for bees, offering aesthetic qualities, serving as a genetic reservoir for improved crops, providing products for human consumption and medicinal use, creating employment opportunities.

Controversial nature of weeds
Weeds have a controversial nature.But to the agriculturist, they are plants that need to be managed in an economical and practical way in order to produce medicine, food, feed, and fiber for humans and animals.In this context, the negative impacts of weeds indirectly affect all living beings.(http://www.weeds.psu.edu).

The term weed in variety of senses
The term weed is used in a variety of senses, generally centering around a plant that is not desired within a certain context.The term weed is a subjective one, without any classification value, since a plant that is a weed in one context is not a weed when growing where it belongs or is wanted.Indeed, a number of plants that many consider "weeds" are often intentionally grown by people in gardens or other cultivated-plant settings.Therefore, a weed is a plant that is considered by the user of the term to be a nuisance.The word commonly is applied to unwanted plants in human-controlled settings, especially farm fields and gardens, but also lawns, parks, woods, and other areas.More vaguely, "weed" is applied to any plants that grow and reproduce aggressively and invasively (Vjanick and Jules, 1979).

Beneficial weeds
Even though weeds may be considered as unwanted for a number of reasons, the most important one is that they interfere with food and fiber production in agriculture, but there are many weeds having ethnomedicinal and pharmacological value, like the phrases in the poem wrote by Gerard Manley Hopkins' "What would the world be, once bereft, of wet and wildness?Let them be left .O let them be left; wildness and wet; Long live the weeds and the wilderness yet."A number of weeds, such as the dandelion (Taraxacum officinale F.H.Wigg.) are edible, and their leaves and roots may be used for food or herbal medicine.Greater Burdock (Arctium lappais L.) common weed over much of the world, and is sometimes used to make soup and other medicine in East Asia.These socalled "beneficial weeds" may have other beneficial effects, such as drawing away the attacks of cropdestroying insects, but often are breeding grounds for insects and pathogens that attack other plants.Dandelions are one of several species which break up hardpan in overly cultivated fields, helping crops grow deeper root systems.Some modern species of domesticated flower actually originated as weeds in cultivated fields and have been bred by people into garden plants for their flowers or foliage.
An example of a crop weed that is grown in gardens is the corncockle (Agrostemma githago L.) which was a common field weed exported from Europe along with wheat, but now sometimes grown as a garden plant (Baker, 1974).White clover (Trifolium repens L.) is considered by some to be a weed in lawns, but in many other situations is a desirable source of fodder, honey and soil nitrogen (Andre, 1988)."Many gardeners will agree that hand-weeding is not the terrible drudgery that it is often made out to be.Some people find in it a kind of soothing monotony.It leaves their minds free to develop the plot for their next novel or to perfect the brilliant repartee with which they should have encountered a relative's latest example of unreasonableness (Christopher, 2001).Weeds have been found to represent a very important component of indigenous pharmacopoeias.The consumption of weedy greens has often been perceived to have a medicinal character (Govindaraj et al., 2011).In ancient Indian literatures all plants were not considered as weeds and it is clearly mentioned that every plant on this earth is useful for human beings, animals and other plants.It is ignorance of human beings as they consider some plants are useful and others as unwanted.Studies conducted by department of Agronomy.(IGAU), Raipur has revealed that weeds are a boon for tile farmers and industries.Uses of weeds of many important agricultural crops have been reported (http://www.ethnologue.com).

Nilgiris
The Nilgiri hills located in Western Ghats, Tamilnadu State, India have a history going backfor many centuries.It is not known why they were called the Blue Mountains (Table 1).Several sources cite the reason as the smoky haze enveloping the area, while other sources say it is because of the kurunji flower, which blooms every twelve years giving the slopes a bluish tinge.It was originally tribal land and was occupied by the todas around what is now the Ooty area, and by the Kotas around what is now the Kotagiri (Kothar Keri) area.The Badagas are one of the major non tribal populations in the district who reside in the mountain.Although the Nilgiri hills are mentioned in the Ramayana of Valmiki (estimated by Western scholars to have been recorded in the second century BCE), they remained all but undiscovered by Europeans until 1602.

Geographical distribution of the Nilgiris district
The district has an area of 2,452.50km 2 .The district is basically a hilly region, situated at an elevation of 2000 to 2,600 masl.Almost the entire district lies in the Western ghats.Its latitudinal and longitudinal dimensions being 130 km (Latitude: 10 -38 WP 11-49N) by 185 km (Longitude: 76° E to 77.15° E).The Nilgiris district is bounded by Mysore district of Karnataka and Wayanad district of Kerala in the North, Malappuram and Palakkad districts of Kerala in the West, Coimbatore district of Tamil Nadu in the South and Erode district of Tamil Nadu and Chamarajanagar district of Karnataka in the East.In Nilgiris district the topography is rolling and steep.About 60% of the cultivable land falls under the slopes ranging from 16 to 35%.The altitude of the Nilgiris results in a much cooler and wetter climate than the surrounding plains, so the area is popular as a retreat from the summer heat.The temperature remains to the maximum of 25°C and reaches a minimum of 0°C (Wang et al., 2011).

Tribal communities in Nilgiris
The Niligiris is gifted with richest flora in which lot of medicinally important plants are present.But many of these plants are considered as weeds or useless plants.But many of these weeds will grow wildly and in cultivated fields.Many of these weeds having ethno medicinal and pharmacodynamic importance but due to lack of proper guidance and scientific documentation, many of these weeds are under destruction due to their short term useless selfish benefits of mankind, but some tribal people like Todas, Kotas, Kurumbas, Paniyas and Kattunayakas are safeguarding this type of plants and using as tribal medicine to cure lot of diseases.

Tribes and weeds of Nilgiris
Todas: Centella asiatica (L) Urban (Apiaceae), locally known as "Vallarai".Plant juice is considered as refrigerant to the body, when given orally.

Kotas:
1. Achyaranthes aspera L. (Amaranthaceae), locally known as "Uthrunk".Leaf paste is applied on cuts, wounds and sores for quick healing.2. Lantana camara L. (Verbenaceae), locally known as "Thusik".Leaf juice is applied to the gum to stop Seed oil warmed and massaged twice a day in arthritic pain.The paste of root is applied for healing of cuts, wounds and boils
In Nepal, the root juice is used to treat pain and constipation bleeding and to reduce tooth-ache.
3. Rubia cordifolia L. (Rubiaceae), locally known as "Sappli Koth".Decoction of stem is orally administered as a restorative tonic.Root juice is given orally to cure jaundice.

Kurumbas:
1. A. aspera L. (Amaranthaceae), locally known as "Nayurvi Geeda".Decoction of whole plant with root is orally given for ease child birth and to mitigate labour pain.2. Ageratum conyzoides L. (Asteraceae), locally known as "Nasar soppu".Leaf juice is orally given as a cure for cough and cold.D) Paniyas: Oxalis corniculata L. (Oxalidaceae), locally known as "Pulichen segae.The whole plant extract in water is orally given for piles and also used as a febrifuge.

Kattunayakas:
1. A. aspera L. (Amaranthaceae), locally known as "Cherukadalai".The whole plant with water is made into paste and applied on body to relive sprain ached in the Joints.
As a trail, in this review, we are trying to expose the important weeds and their pharmacodynamic importance and to educate the society to prevent the destruction of these important weeds and can be made them as economically important plants (Rajan et al., 2002).

Important weeds in Nilgiris
Achyranthes bidentata Blume (Amaranthaceae) Description: A perennial herb grows up to height of 60 to 90 cm.It is hardy to zone 8.It is in flower from August to September, and the seeds ripen from September to October.The flowers are hermaphrodite (have both male and female organs).Achyranthes is an erect perennial with slender rambling branches, elliptical leaves, and greenish white flowers on terminal spikes grows up to 1 m tall.It is commonly known as Ox knee and locally known as Nayuruvi, Shiru-kadaladi.

Ethnomedicinal uses:
In Mizoram (India) the tribes uses leaf paste externally in treatment of leach bites and mosquito bites and the root decoction is used internally as a diuretic (Sharma et al., 2001).

Acalypha indica L. (Euphorbiaceae)
Description: An annual herb to about 80 cm high, having catkin type of inflorescence.It is widespread throughout India, Srilanka and African countries.It has numerous medicinal uses in India and is official in Indian Pharmacopoeia as an expectorant.It is commonly known as Indian nettle, locally known as Poonamayakki, Kuppaimeni.

Ethnomedicinal uses:
In Niligiris the tribal people uses leaf juice to cure ear problems, drowsiness, and digestive problems.The root of this plant is main source of tooth brush (Oudhia, 1999).

Aegeratum conyzoides L. (Asteraceae)
Description: Goat weed is a common tropical annual herbaceous weed.It is an erect softly hairy annual plant which grows up to a height of 2.5 feet.Oppositely arranged leaves are ovate to lance-like, coarsely rounded, and have toothed margin.Numerous pale blue or whitish flower heads are 6 mm across.It is commonly known as goat weed and locally known as Pumppillu, Appakkoti.

Ethnomedicinal uses:
The people of Pandalur village, Nilgiris uses the leaf paste externally used as wound healing activity and insect repellent (Govind raj et al., 2011).

Amaranthus spinosus L. (Amaranthaceae)
Description: It is an annual, erect monoecious herb up to 100(-130) cm tall and it is much branched.The stem is terete or obtusely angular, smooth or slightly hairy, and green or variably suffused with purple, having dense cluster of inflorescences.It is commonly known as spiny amaranth, locally known as mullukkeerai.

Ethnomedicinal uses:
The badaga community of Nilgiris uses the root and leaf decoction of this plant to promote digestion (Sathyavathi and Janardhanan, 2007).

Anthoxanthum odoratum L. (Poaceae)
Description: It is a grass grows in tufts and short lived.It can grow up to 100 cm.The stems are 25 to 40 cm (9.8-16 in) tall, with short but broad green leaves 3 to 5 mm (0.12-0.20 in) wide, which are slightly hairy.It flowers from April until June that is quite early in the season, with flower spikes of 4 to 6 cm (1.6-2.4 in) long and distributed in India, China and South Africa.It is commonly known as vernal grass, and locally known as vanilla grass.

Ethnomedicinal uses:
In west Bengal (India), traditional practitioners uses its tincture as a provocative to hay fever and hay asthma, a medicinal tincture from it is sniffed well into the nose and throat for immediate relief from congestion (Dheeraj et al., 2010).

Argemone mexicana L. (Papavaraceae)
Description: It is a prickly annual having strong branch grows 60 to 90 cm in height with yellow latex; leaves are simple, sessile and spiny; flowers are bright yellow.It is commonly known as Mexican poppy, and locally known as Mullmothakka.

Ethnomedicinal uses:
The badaga community in Nilgiris uses the flower decoction externally to treat eye infections (Sathyavathi and Janardhanan, 2007).

Artemisia nilagirica Clarke. (Asteraceae)
Description: It is an aromatic shrub, 1 to 2 m high, yellow or dark red small flowers, grows throughout India in hills up to 2400 m elevation.This medicinal herb is erect, hairy, often half-woody.The stems are leafy and branched.The leaves are pinnately lobed, 5 to 14 cm long, gray beneath.Mugwort blossoms with reddish brown or yellow flowers.The flowers are freely small and stand in long narrow clusters at the top of the stem.It is commonly known as Indian Wormwood, and locally known as Makkipu.

Ethnomedicinal uses:
The badaga community in Nilgiris uses the leaf and root decoction both externally and internally as mosquito repellent and in treatment of fever (Sathyavathi and Janardhanan, 2007).

Artemisia parviflora Roxb. (Asteraceae)
Description: It is a Perennial shrub growing to 1 m (3ft 3 in).It is hardy to zone 8.It is in flower from August to October, and the seeds ripen from September to October.The flowers are hermaphrodite (have both male and female organs) and are pollinated by Insects.It is commonly known as Japanese worm wood, and locally known as maccipatri.
Ethnomedicinal uses: Tribal people in Nilgiris used the Decoction of leaves as vermifuge and leaves juice is used externally on cuts, wounds and skin infections (Srivastava and Nyishi Community, 2010).

Asclepias curassavica L. (Asclepiadaceae)
Description: It is an evergreen perennial sub shrub that grows up to 1 m (3.3 ft) tall and have pale gray stems.The leaves are arranged oppositely on the stems and are lanceolate or oblong-lanceolate shaped ending in acuminate or acute tips.Like other members of the genus, the sap is milky.The flowers are in cymes with 10 to 20 flowers each.They have purple or red corollas and corona lobes that are yellow or orange.Flowering occurs nearly year round.It is commonly known as Scarlet milkweed and locally known as kammalchedi.

Ethnomedicinal uses:
In Nilgiris, the toda tribes use the leaf paste externally to treat wounds (Rajan et al., 2005).

Bidens biternata (Lour.) Merr (Asteraceae)
Description: It is erect annual herb, up to 1 m.It can be distinguished by the leaves, which are usually 5 to 7 foliolate, the basal pair sometimes further divided.The flowers are yellow, including the ray-florets.It is commonly known as Spanish needles and locally known as mukkuthi.

Ethnomedicinal uses:
In Harayana and Uttarpradesh states of India, people use leaf juice externally for the treatment of sores and ulcers.Root is used for the treatment of tooth ache (Panda, 2000).

Borreria latifolia Aubl. (Rubiaceae)
Description: A branched herb, prostrate, ascendent or erect, usually branched from the base, stems fleshy, 4winged, about 75 cm tall; leaves opposite, elliptical, broadest above the middle, tip broadly and shortly pointed, base tapered, variable in size about 2.5 to 5.0 cm long and 2.5 cm wide, thick, hairy on both sides, short leafstalk; leaf base joined with cup-shaped stipules with bristles on edges.Inflorescence in leaf axils, 0.6 to 1.2 cm across, off white, each flower with hairy calyx of four sepals; stamens 4 and stigma forked; flowers throughout the year; fruit hairy, splitting into two pairs to release seeds.It is commonly known as broad leaf button weed, and locally known as Kudalirakki.

Ethnomedicinal uses:
In Pandalur village, Nilgiris.The people use the aqueous whole plant extract to cure the intestinal and appendages problems (Govind et al., 2011).

Brassica juncea (L.) Czern. (Brassicaceae)
Description: It is a Perennial herb, usually grown as an annual or biennial, up to 1 m or more tall; branches long, erect or patent; lower leaves petioled, green, sometimes with a whitish bloom, ovate to obovate, variously lobed with toothed, scalloped or frilled edges, lyrate-with 1 to 2 lobes or leaflets on each side; upper leaves sub entire, short petiole, 30 to 60 mm long, 2 to 3.5 mm wide, constricted at intervals, sessile, attenuate into a tapering, seedless, short beak 5 to 10 mm long.Rooting depth 90 to 120 cm.Seeds about 5,660 to 6,000 per 0.01 kg (1/3 oz).It is commonly known as mustard plant and locally known as Kadugu.

Ethnomedicinal uses:
The badagas of Nilgiris uses the leaf or seed aqueous decoction externally to treat eye diseases (White patches in pupil) (Sathyavathi and Janardhanan, 2007).

Capsella bursapastoris L. (Brassicaceae)
Description: It grows from a rosette of lobed leaves at the base.From the base emerges a stem about 0.2 to 0.5 m tall, which bears a few pointed leaves which partly grasp the stem.The flowers are white and small, in loose racemes, and produce seed pods which are heartshaped.It is commonly known as shepherds purse and locally known as Mumiri.
Pharmacodynamic uses: Anti-hemorrhagic, in treatment of menorrhagia (Committee on Herbal Medicinal Products, 2010).

Ethnomedicinal uses:
In Indian medicine and Irula tribes of Nilgiris uses leaf juice externally and internally to treat menorrhagia and hemorrhages from renal and genito-urinary tract (Selva et al., 2009).

Centella asiatica (L.) Urb. (Umbelliferae)
Description: It grows in tropical swampy areas.The stems are slender, creeping stolons, green to reddishgreen in color, connecting plants to each other.It has long-stalked, green, reniform leaves with rounded apices which have smooth texture with palmately netted veins.The leaves are borne on pericladial petioles, around 2 cm.The rootstock consists of rhizomes, growing vertically down.They are creamish in color and covered with root hairs.The flowers are pinkish to red in color, born in small, rounded bunches (umbels) near the surface of the soil.It is commonly known as Indian pennywort and locally known as Kuthirai kokku or vallrai.

Ethnomedicinal uses:
The badagas of Nilgiris uses the aqueous whole plant decoction internally incase of body swelling, menstrual pain (Sathyavathi and Janardhanan, 2007).

Cardiospermum halicacabum L. (Sapindaceae)
Description: It is a woody perennial vine distributed almost globally in the tropics.It is a fast growing vine up to 10 feet.Leaves are trifoliate, up to 4 inches long, with highly lobed leaflets.The plant climb with tendrils and needs some form of support.The small white flowers bloom from summer through fall, flowers are not very showy.The fruit is more interesting, from which the plant gets its common name.It is a brown, thin-shelled, inflated angled capsule up to 3 cm across, containing 3 black seeds each, with a white heart-shaped scar.It is commonly known as balloon wine and locally known as Kottavan.

Ethnomedicinal uses:
In Pandalur village, Nilgiris.The people use the leaf decoction internally to cure cold, cough, fever, head ache and other minor diseases (Govind et al., 2011).

Crassocephalum crepidioides (Benth.) S. Moore. (Asteraceae)
Description: It is an erect annual slightly succulent herb growing up to 180 cm tall.Its use is widespread in many tropical and subtropical regions, but is especially prominent in tropical Africa.Its fleshy, mucilaginous leaves and stems are eaten as a vegetable, and many parts of the plant have medical uses.Commonly known as fire weed and locally known as Muyalkadhu.

Ethnomedicinal uses:
In Pandalur village, Nilgiris.The people use the broad leaf extracts are used to cure cut wounds and other inflammation (Govindraj et al., 2011).

Chenopodium ambrosioides L.var. (Chenopodiaceae)
Description: It is an annual or short-lived perennial plant, growing to 1.2 m tall, irregularly branched, with oblonglanceolate leaves up to 12 cm long.The flowers are small and green, produced in a branched panicle at the apex of the stem.Commonly known as worm seed and locally known as Kadu soppu.

Ethnomedicinal uses:
The badagas of Nilgiris uses leaf decoction internally to treat intestinal worms and stomach disorders (Sathyavathi and Janardhanan, 2007).

Chromolaena odorata (L.) R. king and Rabinson. (Asteraceae)
Description: It is a rapidly growing perennial herb.It is a multi-stemmed shrub to 2.5 m tall in open areas.It has soft stems but the base of the shrub is woody.In shady areas it becomes petiolated and behaves as a creeper, growing on other vegetation.It can then become up to 10 m tall.The plant is hairy and glandular and the leaves give off a pungent, aromatic odour when crushed.The leaves are opposite, triangular to elliptical with serrated edges.Leaves are 4 to 10 cm long by 1 to 5 cm wide.Leaf petioles are 1 to 4 cm long.The white to pale pink tubular flowers are in panicles of 10 to 35 flowers that form at the ends of branches.Commonly known as devil weed and locally known as communist.

Ethnomedicinal uses:
In Pandalur village, Nilgiris.The people use Mature leaves used to cure wound healing, leaf extracts used to control mosquito bite and prevent insect bite (Govindraj et al., 2011).

Cirsium wallichii DC. (Asteraceae)
Description: It is an extremely variable plant, 4 to 10 ft tall, with spreading branches.White to purplish-white flower-heads, clustered or solitary, are borne on leafless stalks, or are stalkless.They are 2 to 3.8 cm across, with florets about 1.6 cm.There are lance shaped bracts ending in erect or recurved spines.Stalkless leaves are pinnately lobed, with margins having very long, stout spines.Leaves are hairless above and cottony beneath.Stems are hairy and leafy.Commonly known as Wallichs Thistle and locally known as Bungsee.

Ethnomedicinal uses:
The leaf decoction is used by chotta bhangal community in western Himalaya to treat gastric problems (Sanjay et al., 2006).

Commelina benghalensis L.
Description: It is an annual or perennial herb.Leaves are ovate to lancolate, 2.5 to 7.5 cm long, 1.5 to 4 cm wide, with parallel veination, entire leaf margins, and pubescence on top and bottom.The leaf sheath is covered in red and sometimes white hairs at the apex which is a primary identification factor for this species.Stems can be erect or crawling along the ground rooting at the nodes or climbing if supported, 10 to 30 cm in height, 20 to 90 cm in length, covered in a fine pubescence and dichotomously branched.Flowers are produced in spathes often found in clusters, funnel shaped, fused by two sides, 10 to 20 mm long, 10 to 15 mm wide, on peduncles 1 to 3.5 mm in length.Aerial flowers are staminate, perfect, and chasmogamous with 3 petals 3 to 4 mm long.The upper two flower petals are blue to lilac in color, with the lower petal lighter in color or white and much less prominent.Seeds are rectangular, 1.6 to 3 mm in length, 1.3 to 1.8 mm wide, brown to black in color, and have a netted appearance.Commonly known as tropical spider wort and locally known as Aduthinnathalai.

Dodonea viscose (L.) Jacq. (Sapindaceae)
Description: It is a shrub growing to 1 to 3 m (3.3 to 9.8 ft) tall, rarely a small tree to 9 m (30 ft) tall.The leaves are simple elliptical, 4 to 7.5 cm (1.6 to 3.0 in) long and 1 to 1.5 cm (0.39 to 0.59 in) broad, alternate in arrangement, and secrete a resinous substance.The flowers are yellow to orange-red and produced in panicles about 2.5 cm (0.98 in) in length.The fruit is a capsule 1.5 cm (0.59 in) broad, red ripening brown, with two to four wings.Commonly known as hopbush and locally known as morantha.

Ethnomedicinal uses:
The badagas of Nilgiris uses the stems and leaves externally to treat bone fractures in animals (Sathyavathi and Janardhanan, 2007).

Kalanchoe pinnata (Lam.) Pers. (Crassulaceae)
Description: It is a shrub that grows up to tall of 1.8 m.The pendent flowers are on short, lateral branches on tall, upright, chandelier-like flower stalks.The individual flowers are tubular, 1 inch (2.5 cm) long, enclosed in papery, inflated, green to reddish pink sepals, and have 4 red, narrowly triangular lobes.The flowers dry on the plant and gradually turn a light papery brown color.The leaves have scalloped, dark maroon margins and are green, succulent, opposite, and mostly pinnately compound with 3 to 5 elliptic leaflets.New baby plants can form along the edges of the leaves.Commonly known as miracle leaf and locally known as Runakkalli or Raga kanni.

Ethnomedicinal uses:
The irular tribes of red hills, Tamilnadu, India eat raw leaves daily in empty stomach to treat stomach ulcers (Francisca and Rajendran, 2012).

Lantana camara L. (Verbenaceae)
Description: It is a low, erect or subscandent, vigorous shrub which can grow to 2 to 4 m in height.The leaf is ovate or ovate oblong, 2 to 10 cm long and 2 to 6 cm wide, arranged in opposite pairs.Leaves are bright green, rough, finely hairy, with serrate margins and emit a pungent odour when crushed.The stem in cultivated varieties is often non-thorny and in weedy varieties with recurved prickles.It is woody, square in cross section, hairy when young, cylindrical and up to 15 cm thick as it grows older.Lantana is able to climb to 15 m with the support of other vegetation.Flower heads contain 20 to 40 flowers, usually 2.5 cm across; the colour varies from white, cream or yellow to orange pink, purple and red.Commonly known as sleeper weed or wild sage and locally known as karadikke.

Ethnomedicinal uses:
The badagas of Nilgiris uses the leaf decoction internally to expel worms and externally to treat cuts and wounds (Sathyavathi and Janardhanan, 2007).

Leucas aspera (Wild.) Link. (Lamiaceae)
Description: It is an annual plant that can reach heights of 15 to 60 cm.The leaves can be obtuse, linear or linearly lanceolate or petiolate.The stem quadrangular and contains a wide stele.The epidermis of the stem is covered in a thick waxy cuticle and contains few traversed stomata.The roots contain epidermal cells which are very narrow and closely packed together.It is commonly known as common leucas and locally known as thumbaigidu.

Ethnomedicinal uses:
In Pandalur village, Nilgiris, the people uses leaf decoction used as to cure cold, cough, and skin disorders.Healthy leaves are used for the curry preparation (Govindaraj et al., 2011).

Lobelia nicotianaefolia Roth E & S. (Lobeliaceae)
Description: It is a tall, erect, much branched, somewhat hairy herb, which grows to 1.5 to 3 m in height.The leaves, resembling those of tobacco, are narrowly obovate-lanceolate, the lower ones being 30×5 cm, while the upper ones gradually become smaller.The flowers are large, white, and borne in terminal racemes 30 to 50 cm long.Flowers are 3 to 4 cm long, two-lipped.The sepal is smooth or hairy, narrow, about 1.2 cm long.The capsules are 2-celled, somewhat rounded, and about 1.5 cm in diameter.The seeds are numerous very small, ellipsoids and compressed.It is commonly known as wild tobacco and locally known as upperichedi.

Ethnomedicinal uses:
The kurichiar tribes of wayanad district, Kerala, uses Leaf paste mixed with a pinch of lime is applied to foul smelling wounds for speedy healing (Udayan et al., 2008).

Melilotus indica L. (Fabaceae)
Description: It is an annual herb, sprawling in the absence of a crop, but erect in crops such as wheat.The stem is thin and wiry when mature.A characteristic feature is the appearance of anthocyanin coloring in the form of a red stripe along the midrib of the leaflets which disappears at the time of flowering.The inflorescence is a dense raceme arising from leaf axils, 2 to 3 cm long with 15 to 50 flowers on a short peduncle 1.5 to 2 cm long.Flowers 2 to 2.5 mm long, yellow or pale-yellow, of typical leguminous structure.It is commonly known as Indian sweet clover and locally known as vana methika.

Ethnomedicinal uses:
In Margallah hills (Pakistan), people uses plant paste traditionally leaf as Emollient, in treating swelling, and internally to treat diarrhoea, bowl complaints (Asma et al., 2009).

Mirabilis jalapa L. (Nyctaginaceae)
Description: It is a long-lived (perennial) herb growing up to 2 m high, with a tuberous root.Its leaves are eggshaped in outline with broad end at base (ovate), oblong, or triangular, measuring to 9 cm long.; the leaf tip is acute, base cordate.The leaf stalk (petiole) is 4 cm long.Flowers of occur in groups of 3 to 7; flower stalks more or less absent; flowers are fragrant and open in the afternoon; flowers are tubular, white, pink or red in color, up to 6.5 long by 3.5 wide with 5 to 6 stamens.The fruit is a small, one-seeded capsule (anthocarp).It is commonly known as Four 0 clock flower and locally known as tolahoo.

Ethnomedicinal uses:
The badagas of Nilgiris uses the leaf paste externally to cure wounds (Sathyavathi and Janardhanan, 2007).

Ethnomedicinal uses:
In India, the whole plant is used as a mild laxative medicine, stomachic, antiseptic and emmenagogue, while a decoction of the roots is used to treat eye diseases (Valarmathi et al., 2010).

Nicandra physaloides (L.) Gaertn. ( Solanaceae)
Description: Plants grow to 1 m tall and are vigorous with spreading branches and ovate, mid-green, toothed and waved leaves.The flowers are bell-shaped and 5 cm or more across, pale violet with white throats.The flower becomes lantern-like towards the end of its bloom.It is commonly known as apple of peru and locally known as Ummathakkai.

Ethnomedicinal uses:
The badagas of Nilgiris uses the leaf paste externally to cure wounds (Sathyavathi and Janardhanan, 2007).

Oenothera rosea L´ Hér. ex Ait. (Onagraceae)
Description: It is an annual herb grows up to 2 ft (60 cm) tall.The flowers open at sunrise, are less than 1 inch (2.5 cm) wide, and have cream-colored anthers and 4 eggshaped petals with conspicuous darker veins.The flowers fade to a dark pink color and are followed by clubshaped seed capsules that are widest near the tip.The leaves are both in a basal rosette and on the stems, and they are green, alternate, hairless to sparsely hairy, variably wavy-toothed, and elliptic or oblanceolate in shape.The lower leaves are sometimes pinnatifid at the base.The multiple stems are green, hairy, branched or not, and erect to ascending.It is commonly known as rosy eveningprimrose and locally known as Mexican rose.
Ethnomedicinal uses: In the Himalayas.traditionally, the aqueous infusion of the leaves has been used in hepatic pains and kidney problems (Sumitra et al., 2012).

Opuntia stricta (Ker-Gawler) Haw (Cactaceae)
Description: It is a shrub or tree up to 5 m tall, forming sturdy trunk with age.Joints flattened, narrowly elliptic to ovate, varying in size, 30 to 60 cm long and 6 to 12 cm broad, attenuate below, often acute above, fairly thick, glaucous-green; areoles small to large, raised and woolly, with 3 to 6 radiating, unequally long, greyish white spines up to 3 (-10) cm long, straight or occasionally slightly curved, or spineless (in older plants and some cultivars).Leaves, if developed, are minute, subulate and early deciduous.Flowers about 7 cm long; hypanthium broadly cylindrical, contracted below, with numerous raised areoles spirally arranged, densely wooly and filled with glochidia, occasionally also bearing small spines and minute leaves; petaloid segments yellow or orange.Fruits ellipsoid, about 7 cm long, reddish, succulent, edible.Seeds are about 5 mm long.It is commonly known as noppales and locally known as nagakalli.

Ethnomedicinal uses:
The tribals of Sudi Konda Forest, East Godavari District, Andhra Pradesh used to treat for menorrhagia and metrorrhagia, 10 ml fruit juice mixed with 10 ml 0f rice washed water and a spoonful of sugar is administered twice a day for 3 days till to cure (Aniel et al., 2012).

Oxalis corniculata L. (Oxalidaceae)
Description: It is a annual/perennial growing to 0.1 m (0ft 4 in) by 0.3 m (1 ft).It is a somewhat delicate-appearing, low-growing, herbaceous plant.It has a narrow, creeping stem that readily roots at the nodes.The trifoliate leaves are subdivided into three rounded leaflets and resemble a clover in shape.Some varieties have green leaves, while others, have purple.The leaves have inconspicuous stipules at the base of each petiole.
The fruit is a narrow, cylindrical capsule, 1 to 2 cm long and noteworthy for its explosive discharge of the contained, 1 mm long seeds.It is commonly known as sleeping beauty and locally known as Kunnaullumajigai.

Persicaria nepalensis (Meissn.) H. (Polygonaceae)
Description: A slender spreading or procumbent annual herb, rooting at the lower nodes.Stem pale green, greenish-brown or red to bright red, ascending up to 50 cm, glabrous or with scattered gland-tipped hairs, these more numerous below the ocrea.Leaf lamina with the upper part 0.5-6 × 0.5-3 cm, ovate to ovate-deltate, acute at the apex, tapering or abruptly contracted and decurrent below for up to 1.5 cm forming a false petiole with auricles at the base, glabrous or with scattered hairs, gland-dotted beneath.Ocrea brown, membranous, 6 to 8 mm long, entire at the apex.Flowers in small, pedunculate heads 6 to 9 mm in diameter; heads solitary or paired, c. 12-flowered, subtended by a sessile involucral leaf; peduncles up to 5 cm long, with deflexing glandular hairs below the inflorescence; bracts hyaline, 3.5-5 × 1.5-2.5 mm, broadly lanceolate to ovate.It is commonly known as Nepalese smartweed or knotweed and locally known as Actalaree.

Ethnomedicinal uses:
In Nilgiris, the badaga community uses the root decoction internally to treat fever and vomiting as a home remedy (Sathyavathi and Janardhanan, 2007).

Plantago erosa ex Roxb. (Plantaginaceae)
Description: It is a sub shrub growing to 60 cm (23.5 in) tall.The leaves are sessile, but have a narrow part near the stem which is a pseudo-petiole.They have three or five parallel veins that diverge in the wider part of the leaf.Leaves are broad or narrow, depending on the species.The inflorescences are borne on stalks typically 5 to 40 cm (2.25 to 15.75 in) tall, and can be a short cone or a long spike, with numerous tiny wind-pollinated flowers.Commonly known as plantain and locally known as nelavarikke.

Ethnomedicinal uses:
In Nilgiris, the badaga community uses the whole plant juice uses externally and internally to treat muscle pains (Sathyavathi and Janardhanan, 2007) and the Adi tribe of Arunachal Pradesh, India uses the leaves as vegetable to treat constipation and also to improve digestion (Srivastava and Adi community, 2009).

Plectranthus barbatus Andr. (Lamiaceae)
Description: It is a densely hairy perennial herb, with pale blue flowers arranged in whorls, forming long leafless interrupted spikes.Flowers are up to 2 cm long, tube bent abruptly downward, longer than the sepal cup.Flowers are 2-lipped, the upper lip short, turned back, 3-lobed, the lower much longer, boat-shaped, pointed.Sepal cup is hairy, bell-shaped, with lance shaped, prickly-tipped sepals.Bracts are broadly ovate, pointed, overlapping in bud, soon falling.Leaves are ovate to oblong, blunt, rounded-toothed, short-stalked, 5 to 8 cm long.They are arranged in opposite pair's perpendicular to each other, along a 1 to 3 ft tall stem.It is commonly known as Indian coleus and locally known as karpuravalli.
Ethnomedicinal uses: Kothas, the native tribes of Chaitanya et al. 3521 Trichigadi in Nilgiris, South India consider the decoction of tuberous roots as tonic for well being (Rakshapal et al., 2011).

Description:
The genus primarily grows in northern temperate regions.They vary widely from prostrate herbaceous annual plants under 5 cm high, others erect herbaceous perennial plants growing from 3 to 4 m tall and yet others perennial woody vines growing from 20 to 30 m high in trees.Several are aquatic, growing as floating plants in ponds.The smoothedged leaves range from 1 to 30 cm long, and vary in shape between species from narrow lanceolate to oval, broad triangular, heart-shaped, or arrowhead forms.The stems are often reddish or red-speckled.The small flowers are, pink, white, or greenish, forming in summer in dense clusters from the leaf joints or stem apices.It is commonly known as tear thumb and locally known as Kappu annu gidu.

Prinsepia utilis Royle. ( Rosaceae)
Description: It is a spiny shrub, growing up to 1 to 5 m tall.Branches are grayish green, robust, branchlets green to grayish green, angled, brown velvety to hairless.Spines are up to 3.5 cm long.Winter buds are purplish red, ovoid to oblong, hairless.Leaf stalks are about 5 mm long.Leaf blade is oblong to ovate-lance shaped, 3.5 to 9 cm long, 1.5 to 3 cm wide, base broadly wedge-shaped to rounded, margin toothed, tip pointed to long pointed.Flowers are borne in racemes in leaf axils, or on short branchlets, 3 to 6 cm, many-flowered.Flowers are 1 cm in diameter.Flower-stalks are 4 to 8 mm, up to 1 cm in fruit.Flower base is cup-shaped, outside brown velvety.Commonly known as Himalayan cherry and locally known as cherara.
Ethnomedicinal uses: In Garhwal, Himalayas, seed oil warmed and massaged twice a day in arthritic pain.The paste of root is applied for healing of cuts, wounds and boils.

Ricinus communis L. (Euphorbiaceae)
Description: It is a fast-growing, suckering perennial shrub that can reach the size of a small tree (around 12 m or 39 feet), but it is not cold hardy.The glossy leaves are 15 to 45 cm (5.9 to 18 in) long, long-stalked, alternate and palmate with 5 to 12 deep lobes with coarsely toothed segments.In some varieties they start off dark reddish purple or bronze when young, gradually changing to a dark green, sometimes with a reddish tinge, as they mature.The leaves of some other varieties are green practically from the start, whereas in yet others a pigment masks the green colour of all the chlorophyll-bearing parts, leaves, stems and young fruit, so that they remain a dramatic purple-to-reddish-brown throughout the life of the plant.The flowers are borne in terminal panicle-like inflorescences of green or, in some varieties, shades of red monoecious flowers without petals.The male flowers are yellowish-green with prominent creamy stamens and are carried in ovoid spikes up to 15 cm (5.9 in) long; the female flowers, born at the tips of the spikes, have prominent red stigmas.It is commonly known as castor oil plant and locally known as Aamanakku.

Ethnomedicinal uses:
In Nilgiris, the tribal people use the seed decoction in treatment of stomach pain and dysentery and externally the seed oil is applied over skin to remove black scars (Sathyavathi and Janardhanan, 2007).

Rubus ellipticus Smith. ( Rubiaceae)
Description: It is a stout evergreen shrub with prickly stem that grows approximately 4.5 m tall.Its stems are covered with prickles and reddish hairs.Leaves are alternate and compound with three round to blunt leaflets of 5 to 10 cm long.The underside of the leaves is lighter than the upper surface and covered with downy hairs.The flowers are small and white with five petals.The fruit is a round yellow cluster of droplets which is easily detached from the receptacle.It is commonly known as yellow Himalayan raspberry and locally known as Tuppa mulli.

Ethnomedicinal uses:
The tribal of Nilgiris uses the decoction of this plant as an abortifacient (Vadivelan et al., 2000).

Rumex nepalensis Sprengel. (Polygonaceae)
Description: A stout, perennial herb up to 1.8 m tall.Stems green to greenish-brown, hollow, glabrous, striate.Leaf lamina 25-45 × 7-9 cm, oblong-lanceolate to linearlanceolate, obtuse or rounded at the apex, cuneate at the base, entire or crisped on the margin, glabrous or with scattered papillae on the undersurface, the upper leaves smaller; petiole of basal leaves 13 to 30 cm long.Flowers hermaphrodite, pedicellate, pendulous, in whorls borne in terminal racemose panicles; the basal whorls in the axils of foliaceous bracts; pedicels filiform, articulated near the base.Commonly known as dock weed and locally known as gongu.
Ethnomedicinal uses: In Nilgiris, the root and leaves paste is taken internally to treat jaundice (Sathyavathi and Janardhanan, 2007).

Sarothamnus scoparius L. (Fabaceae)
Description: It typically grow to 1 to 3 m (3-9 ft) tall, rarely to 4 m (13 ft), with main stems up to 5 cm (2 in) thick, rarely 10 cm (4 in).The shrub have green shoots with small deciduous trifoliate leaves 5 to 15 mm long, and in spring and summer is covered in profuse golden yellow flowers 20 to 30 mm from top to bottom and 15 to 20 mm wide.Flowering occurs after 50 to 80 growing degree days.In late summer, its legumes (seed pods) mature black, 2 to 3 cm long, 8 mm broad and 2 to 3 mm thick; they burst open, often with an audible crack, forcibly throwing seed from the parent plant.It is commonly known as Scotch broom and locally known as kothikeerai.

Ethnomedicinal uses:
In Nilgiris, the tribes use the leaf decoction internally as a good diuretic (Sathyavathi and Janardhanan, 2007).

Siegesbeckia orientalis L. (Asteraceae)
Description: It is an annual herb growing to 1.2 m (4 ft).The flowers are hermaphrodite (have both male and female organs.Leaves ovate, florets in solitary, axillary or terminal, heterogamous head, fruit achene and obovoid.It is commonly known as Holy herb and locally known as kadambu. Major constituents: Phenols, tannins, lignans, flavonoids, sterols, phenolic compounds, glycosides and Triterpenoids (Geetha and Gopal, 2011).

Ethnomedicinal uses:
In Nilgiris, the tribal people use the plant extract externally to treat various skin infections (Sasikumar et al., 2007).

Silybum marianum (L.) Gaertn (Asteraceae)
Description: It grows 30 to 200 cm tall, having an overall conical shape with a approx.160 cm max.diameter base.The stem is grooved and more or less cottony, and with the largest specimens the 'trunk' is hollow.The leaves are oblong to lanceolate.They are either lobate or pinnate, with spiny edges.They are hairless, shiny green, with milk-white veins.The flower heads are 4 to 12 cm long and wide, of red-purple colour.They flower from June to August in the North or December to February in the Southern Hemisphere (Summer through Autumn).The bracts are hairless, with triangular, spine-edged appendages, tipped with a stout yellow spine.The achenes are black, with a simple long white pappus, surrounded by a yellow basal ring.Commonly known as milk thistle and locally known as dudh patra.

Ethnomedicinal uses:
In Nilgiris, Kattunayakas tribes use the leaves and seed decoction internally to treat burning pain in anus and jaundice pain (Selvaraj et al., Chaitanya et al. 3523 2009).

Stellaria media L. (Caryophyllaceae)
Description: It is an annual herb growing to 0.1 m (0ft 4in) by 0.5 m (1ft 8in).Cotyledons are ovate, 1-12 mm long by 0.25-2 mm wide, with a slender reddish hypocotyl that is sparsely hairy, stems are usually running prostrate along the ground, rooting at the nodes, with the upper portion erect or ascending and freely branching.Stems are light green in color and with hairs in vertical rows.
Fruits are oval, one-celled capsule, whitish in color, containing numerous seeds and flowers are alone or in small clusters at the ends of stems.Flowers are small (3-6 mm wide) and consist of 5 white petals that are deeply lobed, giving the appearance of 10 petals.It is commonly and locally known as chick weed.
Ethnomedicinal uses: In Dibrugarh District (Assam, India).The whole plant paste and decoction is used externally and internally in treatment of skin diseases, bronchitis, rheumatic pains and dysmenorrhoea (Dilip et al., 2005).

Taraxacum officinale F.H. Wigg. (Asteraceae)
Description: It grows from generally unbranched taproots and produces one to more than ten stems that are typically 5 to 40 cm tall but sometimes up to 70 cm tall.The stems can be tintled purplish and produce flower heads that are held as taller than the foliage; the stems can be glabrous or are sparsely covered with short hairs.It is commonly known as Dandelion and locally known as Kanphul.

Ethnomedicinal uses:
The Irula and Kurumba tribes of Niligiris use the fresh plant juice internally against liver diseases and intermittent fevers (Selvaraj et al., 2009).

Tephrosia purpurea (L.) Pers. (Fabaceae)
Description: A small spreading perennial herb grows up to 50 cm in height.Leaves compound, imparipinnate, with 11 to 21 leaflets, oblong-lanceolate, small; flowers red or purple, in axillary racemes.Fruits pod, containing 4 to 8 seeds.It is commonly known as wild indigo and locally known as kavali.
Ethnomedicinal uses: In Jharkhand, India, the tribal uses the boiled extract of plant is a vermifuge and used to kill the intestinal worms (Hari et al., 2012).Tithonia diversifolia (Hemsl.)A.Gray.(Asteraceae) Description: It is 2 to 3 m (6.6-9.8 ft) in height with upright and sometimes ligneous stalks in the form of woody shrubs.The large, showy flowers are yellow to orange colored and 5 to 15 cm wide and 10 to 30 cm long.Leaves are sub-ovate, serrate, acute, 10 to 40 cm long, simply or mostly 3 to 7 lobed, somewhat glandular, and slightly grayish beneath.The seeds are achenes, 4angled, and 5 mm long seeds are spread by wind.It is commonly known as tree marigold and locally known as Kattu suryakanthi.
Ethnomedicinal uses: In Nigeria, the decoctions of its various parts are used for the treatment of malaria, diabetes mellitus, sore throat, liver and menstrual pains ( Ogundare, 2007).

Trifolium repens L. ( Fabaceae)
Description: This perennial plant is about 6" tall, branching from the base.Initially, it produces several compound leaves from a short stem that grows only a little, after which this stem rapidly elongates and becomes up to 1' long.These elongated stems sprawl along the ground and have the capacity to root at the nodes.They are hairless and light green.The alternate compound leaves are trifoliate and hairless.They occur at intervals along the elongated stems and have long hairless petioles.The leaflets are obovate or ovate.Their margins are finely serrate.Across the upper surface of each leaflet are white markings in the form of a chevron (an upside down "V"), although for this species these markings are often degenerate, irregular, or absent.Each leaflet is about ¾" long and about half as wide.At the base of each petiole there are a pair of small lanceolate stipules that are light green and membranous; sometimes they wrap around the elongated stems.Each stipule is less than ½" in length.It is commonly and locally known as white clover.

Ethnomedicinal uses:
The naga tribes of India use the whole plant decoction as deworming agent (Hornoy et al., 2012).

Urtica parviflora Roxb.( Utricaceae)
Description: An erect biennial herb grows up to 60 cm in height.Leaves are solitary, alternate, dentate, chordate base, with minute hairs, which produce intense itching when touched.Flowers are minute, greenish yellow, seen in long axillary panicles, with numerous minute seeds.It is commonly known as Nettle and locally known as aanathumba.
Ethnomedicinal uses: In Sikkim, the leaves and fresh roots are used for the treatment of fracture, dislocation of bones, boils, and decoction of herb is used as a febrifuge (Srivastava, 1993).

Verbascum thapsus L. (Scrophulariaceae)
Description: It is a dicotyledonous plant that produces a rosette of leaves in its first year of growth.The leaves are large, up to 50 cm long.The second year plants normally produce a single unbranched stem usually 1 to 2 m tall.In the East of its range in China, it is, however, only reported to grow up to 1.5 m tall.The tall pole-like stems end in a dense spike of flowers that can occupy up to half the stem length.All parts of the plants are covered with star-shaped trichomes.This cover is particularly thick on the leaves, giving them a silvery appearance.It is commonly known as Common Mullein and locally known as kadu gidu.
Ethnomedicinal uses: In Nilgiris, the badaga tribal people uses the leaf paste externally in treatment of cuts and wounds as an antiseptic (Sathyavathi and Janardhanan, 2007).

Conclusion
This review article has a paramount importance creating awareness for the public regarding the medicinal importance of weeds removing the misunderstanding from their minds that they consider it as useless.Moreover, it helps to motivate the public to safe guard these medicinally important weeds from all in once destruction.It is a misconception in people minds to consider all weeds as useless or hurdles to public, as some of these weeds having good ethno medicinal values globally and is good sources for new drug discovery and grows naturally in bulk, no need of specialized good agricultural practices, easily available in all the seasons.It is our duty to safe guards these beautiful nature gifts.
Globally some of these weeds are used as ethnomedicinal aids in treatment of fevers, pains, inflammations, microbial infections, worm infestations, cancer, wounds etc.But very less scientific validation is available on this area so there is a great scope for the phytoscientists to work on this area in order to explore the phytochemical or pharmacological importance of weeds.It is the duty of phytoscientists establish the scientific validation for these medicinally important weeds, so that the misconception of weeds as useless or public hurdle will convert to weeds as a pharmacologically and economically valuables.

Table 1 .
Pharmacodynamic and ethnomedicinal uses of weed speices in nilgiris.
Nettle Utricaceae Akaloids, flavanoid, terpenoids, glycosides, saponins and tannins Wound healing, hepatoprotective, Antioxidant and hypoglycemic activity The leaves and fresh roots are used for the treatment of fracture, bones, boils, and febrifuge