Traditional Herbal Knowledge among the Inhabitants: A Case Study in Urgam Valley of Chamoli Garhwal, Uttarakhand, India

The Indian Himalaya is rich in plant species, including many medicinal plants, greatly valued by local inhabitants for health care needs. The study in Urgam Valley of Uttarakhand, India, is to identity and document traditional knowledge of medicinal plants. The study revealed high consensus on medicinal plant usage, with 51 species belonging to 31 families used for local health care. Number of species and uses known increases with age, and elders and specialist healers retain higher levels of traditional medicinal plant knowledge, having unique knowledge of medicinal plants and their uses as well as preparation.


Introduction
India is rich in floral diversity, with more than 17,000 angiosperm species, 64 gymnosperms, 1,200 pteridophytes, 2,850 bryophytes, and 2,021 lichens [1]. Out of the total, 7,500 species have been reported to have medicinal uses [2]. Diverse topography and climatic conditions provide the Indian Himalaya with an especially rich medicinal plants, whereby alpine areas being the major source of important medicinal plants.
Inhabitants of rural and remote areas still rely on plants as a major component of their health care systems. Indigenous medicines provide considerable economic benefits to local people [3]. The World Health Organization (WHO) mentioned that about 25% of modern medicines are developed from plant sources used traditionally; and research on traditional medicinal herbal plants leads to discovery of 75% of herbal drugs [3,4] Locals acquire knowledge of the economic values and medicinal properties of many plants through need, observation, trial and error, and the transmitted experiences of elders. Often, knowledge is concentrated in specialist healers. Most diseases cured by local herbalist are common problems such as respiratory diseases, aches and pains, wounds, and musculoskeletal ailments. Inhabitants often use local medicinal plants without prior advice of local traditional healers because they are using these plants since generations [5]. This knowledge may be passed secretively from one generation to the next through word of mouth [6] or inherited via medico-spiritual manuscripts [7]. Although knowledge of these valuable plants is often restricted within lineages or in other ways, ensuring that the younger generations in these areas acquire this knowledge is essential to its continuity in use and sustainability. Medicinal plant richness of the Indian Himalaya is exemplified in Garhwal Himalaya, within northwestern India. This study focused on traditional herbal medicines of Urgam, a mountain valley in the Garhwal Himalaya rich in medicinal plants which are still used by local inhabitants and specialist healers.   The questionnaires were then compiled detailed information for each plant on local name, life form, local uses, method of use or drug preparation, and amount of use (dose). Apart from the general population survey of villagers and shepherds, local male (Vaidyas) and female specialists (Daai) were also sought to compare their knowledge to that of the general population.

Plant Collection and Identification.
Voucher specimens were prepared for the traditionally used plants documented in this study. Specimens were identified using Flora of District Garhwal [8] and Flora of Chamoli [9] and in comparison with the specimens of Garhwal University Herbarium, Srinagar Garhwal (GUH Use. An informant consensus factor (ICF) was used to measure the consensus in plant use for a given illness treatment in the study area. To develop this consensus, all treated diseases were grouped into nine categories: (a) gastrointestinal disorders, (b) fever and aches, (c) diseases of the skin, (d) remove weakness, immunomodulator, anaemia, (e) ophthalmologic complaints, (f) poisonous bite, (g) dental problems, (h) ear ache, and (i) hearing problems. Within these categories, ICF was calculated according to the following formula [11]: where Nur refers to the number of use-reports for a particular ailment category and Ntaxa refers to the number of taxa used for a particular ailment category by all informants. ICF value ranges from 0 to 1. A high ICF value (close to 1.0) indicates "consensus" indicating relatively few taxa is reported by a large proportion of informants for an ailment category.

Comparing Plants and Uses across Informants.
To test whether the traditional medicinal plant knowledge varied with age, the total plants or total uses reported by each informant (excluding healers) were summed up and ran linear regressions and natural spline regressions, using the package splines [12] in the R statistical framework (Version 3.3.0). To test whether healers reported a different set of plants and uses altogether, the 89 informants who had reported more than 10 species were compared. A matrix with plants as columns and informants were constructed as rows, calculated Bray-Curtis distances among each pair of informants based on how similar their answers were, and used nonmetric multidimensional scaling to plot informants based on these distances. To calculate the significance of specialist healer status, the fit of this factor on the location of informants in the ordination space was compared to that of 999 randomized shuffles using the R package vegan [13].

Demographic Features of Informants.
A total of 96 people were interviewed consisting of seven local healers from both female (Daai) and male (Vaidyas healers). Most (48 participants or 50%) were 41-60 years old with 27 informants or 28.1% were 40 years old and younger. Seventeen were illiterate, while 4 young practitioners held a tertiary education (degree/diploma) ( Table 1).

Comparing Plants and Uses across Informants.
Inhabitants of Urgam Valley have a generally strong knowledge of medicinal plants, with informants reporting on average 18 plant species and 13 uses. This knowledge increases with age: linear regressions on age significantly increase for uses (y=0.18 * age+5.3, p<0.01, r-squared = 0.39) and for plant species (y=0.24 * age+5.5, p<0.01, r-squared = 0.37). The natural spline regressions show that this effect is less steep at higher ages (significantly nonlinear): that is, there is less increase in knowledge after about age 50 ( Figure 6(a)). and anti-cancer [25] Evidence-Based Complementary and Alternative Medicine 5      [76] 10 Evidence-Based Complementary and Alternative Medicine    Healers, who were excluded from this analysis, report more plants and more uses than the average predicted value for their age (Figure 6(b)). Elders also tend more to report learning from their parents as a source of knowledge and tend to easily identify plants and their localities and characters, while some younger informants struggled to give information.
Ordinations show similarity between informants by plotting those who reported more similar lists of plants or more similar lists of species are closer together (Figure 7). Although there is a great deal of overlap, specialist healers do report a significantly different set of plants (p=0.01, r-squared=0.06) and uses (p<0.01, r-squared=0.07) than nonspecialists. For instance, Dioscorea bulbifera, Polygonatum verticillatum, Jurinea macrocephala, and Prunus persica were only reported by healers; Bergenia ciliata, Allium cepa, and Cinnamomum tamala were more widely reported, but most frequently by healers (all healers reported these plants, compared to only <50% of nonhealers). Likewise, infection after breakage of hair in body "Baaltod" was only reported by healers, and Control blood pressure' and "Ear ache" were reported more widely, but much more frequently by healers (all healers reported these uses, compared to <50% of nonhealers).

Discussion
Medicinal plants are globally used in local health care by ethnic communities of the world and the knowledge of folk medicine is being documented throughout the world.
Our  14 Evidence-Based Complementary and Alternative Medicine  uses and of medicinal plants is higher in elders (bujurg), who learnt this knowledge from their parents or forefathers and associated plant medicine with positive attitudes, but also with regular practice of identifying and using plants to treat different ailments. We also showed that specialists tend to report different and unique species and were associated with some species that were widely reported, but most consistently reported by specialist. For instance, Bergenia ciliata (Haworth) Sternberg was reported here used for stones by every healer. This is a widely used plant, with similar use citations reported locally [8,105] but also across the greater Himalayan region for a variety of uses [106] Most commonly mentioned plants across the general population have also been reported previously for similar uses from the region. For instance, Picrorhiza kurrooa Benth., which was reported by nearly every informant, is used for fever similar to Bhat et al. [107], where it was reported for fever and stomach ache. Zanthoxylum armatum DC., reported by 95 informants for cleaning teeth and toothache, was reported for similar uses locally [108] and more distantly by Abbasi et al. [109]. Berberis lycium Royle DC., reported by 92 informants for conjunctivitis, was also reported by Gaur [8] for ophthalmia and Bhat et al. [107] for eye irritation. Aconitum heterophyllum Wall.ex Royle root powder, reported by 69 informants for stomach ache and fever, was also reported elsewhere [107,108] for the same uses. More distantly, the species is also reported for dysentery [106] in Northern Pakistan. Juglans regia L., reported by 56 for cleaning teeth and treatment of skin diseases, was also reported for similar uses from Northern Pakistan [106,110] while, in Uttarakhand, Gaur [8] reported its use as fishery, dye, fungicide, and insecticide. Dactylorhiza hatagirea (Don.) Soo., reported by 39 for cut and wounds and stomach ache, was also reported for similar uses locally [107]. Aconitum balfourii Stapt., which was uncommonly reported for snake bites in this study, was reported previously for similar uses: use in poisonous skin diseases [107], as antidote of snake and scorpion sting, and for rheumatism, arthritis and paralysis from Nanda Devi Biosphere reserve [111], and leprosy [108].

Conclusion
The study suggests that while there remains a rich knowledge of medicinal plants in Urgam Valley, most knowledge is held by elders (bujurg) and specialist healers (vaidyas and daai). Knowledge of medicinal plants is important and frequently used by local inhabitants to support their health care. Pharmacological activity on most of the plants is yet unknown so medicinal plants use in Urgam might be helpful in new drug discovery and pharmacological properties. Most of the highly useful plants of Himalaya are threatened with overexploitation and irregular harvesting and now limited to few pockets. Ex situ and in situ conservation should be implemented to conserve biodiversity and these valuable medicinal plants. Cultivation, rather than wild-harvest, of threatened valuable medicinal plants may support the traditional uses documented here, while also protecting wild populations.

Data Availability
The data used to support the findings of this study are available from the corresponding author upon request.

Conflicts of Interest
The authors declare that there are no conflicts of interest.