Local people’s interaction with Wejig-Mahgo-Waren Massif Forest in Southern Tigray, Ethiopia

Abstract

Background

Ethiopia is home to a rich diversity of traditional knowledge and practices, including the use of medicinal plants for healthcare. This study investigates the ethnobotanical knowledge and use of medicinal plants among communities residing near the Wejig-Mahgo-Waren Massif Forest in Southern Tigray, Ethiopia, and compares these findings with the broader Ethiopian ethnobotanical database.

Methods

Data were collected through semi-structured interviews with 309 randomly selected informants and 30 key informants. Ethnobotanical analytical tools, including preference ranking, informant consensus factor (ICF), and fidelity level (FL), were employed. A comparative analysis was conducted with the Ethiopian ethnobotanical database to assess novel reports and commonalities across regions.

Results

Fifty-two plant species were documented for treating human and livestock ailments. The study revealed significant differences in medicinal plant knowledge among social groups, with men, older individuals, and illiterate informants demonstrating greater knowledge. A comparative analysis with the Ethiopian ethnobotanical database highlighted both commonalities and unique uses of medicinal plants in the study area. The study shares a 51.6% similarity index with previous Ethiopian ethnobotanical studies. However, livestock medicinal plant similarity is low (7.9%), indicating highly localized ethnoveterinary practices. Dermatological diseases scored the highest ICF value (0.98), and Verbascum sinaiticum had the highest FL (96.15%).

Conclusion

The study underscores the critical role of the Wejig-Mahgo-Waren Massif Forest in supporting traditional medical practices. The findings highlight the need for conservation and scientific validation of these medicinal plants to ensure their sustainability and benefits for future generations. The comparative analysis provides valuable insights into the ethnobotanical practices across Ethiopia, emphasizing the importance of cross-cultural interpretations in ethnobotanical research.

Introduction

In many developing countries, people mostly rely on ethnomedicinal knowledge to treat diseases, because Western based health care system is inefficient due to poor staffing or because Western drugs are expensive. Ethnomedicine is a system of maintaining health and curing diseases based on folk beliefs and traditional knowledge, skills, methods and practices. Ethnomedicinal knowledge is disappearing because of rapid socio-economic, environmental, and technological changes. Therefore, ethnomedicinal knowledge must be systematically documented and conserved it is lost forever [1].

The connection of people with plants in earlier times is evidenced as they created durable representations of plants, drawing them in stone or molding them in clay. Such images not only provide modern ethnobotanists with clues concerning plant origins, but functional as tangible indicators of the importance of these people attached to plants [2]. From earliest times, humankind has used plants in attempting to cure diseases and related physical sufferings. Primitive people in all ages have also had some knowledge of medicinal plants, derived as the result of trial and error [3].

Ethiopia is home to many languages, cultures and beliefs, which have in turn contributed to the high diversity of traditional knowledge and practices of the people which, among others, includes the use of medicinal plants. Plants have been used in the country both in the prevention and cure of various diseases of humans and their animals from time immemorial [4]. It was reported that, 80% of the Ethiopian population depends on tradition medicine for their health care; more than 95% of traditional medicinal preparations are of plant origin [5].

In Ethiopia like many of the developing countries, medicinal plants have not been well documented and scientifically validated. Similar to other region of Ethiopia, people living in Tigray in general and the study area in particular have traditional practices which they accumulated for long times and has been transferred across generations to treat both human and livestock ailments. However, as most of the information held by traditional healers and local people passed to generation by word of mouth, there is a possibility for it to be lost in the process. Limited research works had been conducted in the Tigray region on some medicinal plants used for curing human and animals with specific ailments. This study aims to document and analyze the ethnobotanical knowledge of medicinal plants used by local communities and to conduct a comparative statistical analysis with the Ethiopian Ethnobotanical Database.

Materials and methods

Wejig-Mahgo-Waren massif forest is an elongated chain of natural forest that is located in the Southern Tigray at about 630 km North of Addis Ababa or some 120 km south of Mekelle town, the capital of Tigray Regional State. It is located between 12° 47ʹ and 12° 58ʹ North latitude and 39° 30ʹ-39° 48ʹ East longitudes with altitudinal variation from 1627 to 2970 m.a.s.l., covering a total area of 8,772 ha.

According to Ministry of Environment and Forestry of Ethiopia [6], Wejig-Mahgo-Waren massif forest is partly degraded; and thus, there are intact areas in which this study was conducted. The patches of remnant natural forests belong to the Dry Afromontane forest types with dominant trees, like Juniperus procera, Olea europaea subsp. cuspidata, and Acacia abyssinica. The vegetation type in most of the area is of the secondary forest type. The forest area falls within five sub-districts of three districts (Alaje, Hintalo Wajirat, and Raya Azebo) (Fig. 1). The following were districts (sub-districts) found in and near to the forest: Alaje (Ayba), Hintalo Wajirat (Tsehafti) and Raya Azebo (Tsigea, Ebo).

Fig. 1

Map of Ethiopia showing Tigray Regional State and the study area (Hintalo Wajirat, Alaje and Raya Azebo districts with the forest area shaded green) (developed using ArcGIS 10.4.1)

According to 1998–2017 rainfall data, the study area has a high rainfall distribution in July and August and a little in March, April and May. The average maximum temperature in the study area is recorded in June (25.68 °C) and May (24.90 °C). On the other hand, average minimum temperature is recorded in December (5.47 °C) and January (6.88 °C) [7].

The topography in the study area includes hill areas, flat lands, mountains, and valleys. The dominant soils are Leptosols and Regosols. The major crops growing in the area are teff, maize, barley, wheat, beans, peas, lentils, sorghum and pepper. Livestock husbandry is an integral part of the mixed farming system in the study area.

Tigrigna is an official language in Tigray region which is the language mostly spoken by the local people of the study area. Based on the population census of 2007 by the Ethiopian Central Statistical Agency, the total population of Alaje, Hintalo Wajirat and Raya Azebo districts is 107,972, 153,505 and135,870, respectively.

Sample size determination and selection of site and informants

Selections of districts were carried out by considering sub-districts and villages that were found in the forest and nearby villages. The following were sub-districts (villages) found in and around the forest: Ayba (Arera), Tsehafti (Waren, Ago), Ebo (Mahgo) and Tsigea (Wejig) (Table 1). Ethnobotanical data were collected between April 2017 and September 2018 covering all the seasons. The total number of informants involved in the ethnobotanical survey from the study sites were 339 (200 male and 139 female). Informants’ ages ranged from 22 to 86 years (254 were < 50, whereas 85 were > 50 years old). Three hundred nine informants were randomly selected for collecting data about medicinal plants uses, while thirty key informants (five to eight from each of the study villages) were preferentially selected with the help of local administrators, elders and other community members for ranking exercise and collection of specific diseases cured by few traditional healers. The key informants included elders, and knowledgeable persons. Oral informed consent was obtained from each informant who participated in this study after explaining the purpose of the study. The GPS coordinates and altitude were recorded on-site using a handheld GPS device. Ecological characteristics were documented through field observations. Information on ethnicity, language, religion, and population size was gathered through structured interviews with community members and verified with local administrative records during the study (Table 2).

Table 1 Number of households included in the study sub-districts and villages that were found around the forest

Table 2 Study districts with corresponding items recorded

The sample size for collecting quantitative data for this research to ensure the required representative sample size of households from the five sub-districts was determined using the method in Bartlett et al. [8]. According to sub-districts administrations, the total number of households in five villages of Arera, Ago, Mahgo, Waren and Wejig were 2236. Thus, the total required sample size was 339 informants.

Data collection

Ethnobotanical data were collected through semi-structured interview and guided field walks [9]. Interviews were conducted in the local language of the people, which is Tigrigna. The plant specimens of the claimed medicinal plants were brought to the National Herbarium of Addis Ababa University for identification, confirmation and final deposition.

Data analysis

Data were summarized using Microsoft Office Excel 2010 computer programme and SPSS 20. Descriptive and Inferential (Ttest) statistical methods were employed to analyze and summarize the ethnobotanical data.

Preference ranking [9] was conducted by eight key informants to identify medicinal plants used for febrile illness. Informant Consensus Factor (ICF) was obtained by “Number of use citation (reports) in each disease category (n_ur) minus the number of species used (n_t), divided by the numbers of use citations (reports) in each category minus one” [10]. The disease categories in the study area included: (1) gastrointestinal, (2) dermatological, (3) external injuries, bleeding and snakebites, (4), evil eye, (5) febrile illness, (6) oral, dental and pharyngeal, (7) sensory and nervous system and (8) other categories.

The relative healing potential of each reported medicinal plant used against human and livestock ailments was evaluated using an index of fidelity level (FL) [11] given below:

FL = Ip/Iu X 100, where Ip is the number of informants who independently cited the importance of a species for treating a particular disease and Iu is the total number of informants who reported the plant for any given disease.

Results

Medicinal plants reported

Fifty-two plants species were used to treat human and/or livestock diseases in the study area. Growth habits of the medicinal plants included shrubs (24 species, 46.15%), trees (13 species, 25.00%), herbs (11 species, 21.15%) and climbers (4 species, 7.69%).

Diseases treated

The reported medicinal plants were used to treat 50 human and five livestock diseases. Of the total number of medicinal plants, 45 (68.18%) were used to treat human diseases (Table 3), 8 (12.12%) were employed to treat diseases of livestock (Table 4) and 13 (19.69%) were used against diseases of both human and livestock (Table 5).With regard to human diseases, febrile illness was the one, against which, a high number of medicinal plants (6 species) were prescribed, followed by evil eye (5 species), jaundice (4 species) and wound (4 species). The diseases cancer, cholera, malaria and snakebite were treated by 3 species each. Both eye infection and dislocation of joints were the prevailing livestock diseases in the study area against each three species were used, followed by those used against leech infestation (2 species).

Table 3 Medicinal plants used to treat only human diseases

Table 4 Medicinal plants used to treat livestock diseases

Table 5 Medicinal plants used to treat both human and livestock diseases

The study shares a 51.6% similarity index with previous Ethiopian ethnobotanical studies. However, livestock medicinal plant similarity is low (7.9%), indicating highly localized ethnoveterinary practices (Table 6). A comparative analysis with the Ethiopian ethnobotanical database revealed both commonalities and unique uses of medicinal plants in the study area (Table 7). For example, Eucalyptus globulus and Withania somnifera were commonly reported across multiple regions, while Verbascum sinaiticum was uniquely prominent in the study area for treating dermatological diseases. The study also identified novel uses of certain plants, such as Clematis simensis for treating kidney ailments, which had not been previously documented in other Ethiopian studies.

Table 6 Distribution and similarity index of medicinal plant species in the study

Table 7 Novel medicinal plant species and their uses

Mode of preparation

It was found out that most remedies were processed by crushing (83.33%), chewing (9.26%) and boiling (4.63%). The majority of the remedies were prepared from fresh materials only. Some remedies were prepared from either dried or fresh materials while few were prepared from dried materials only. Considerable preparations were made from mixture of different plant species with the use of water and different additives, such as honey, butter, water and cheese. The additives were believed to reduce poisonings, improve flavor and mitigate other side effects.

Modes of administration, dosage and antidotes

Informants indicated that drinking was the most employed mode of administration with 41 (34.75%) reports, followed by tying 28 (23.73%), smoking 15 (12.71) and washing 11 (9.32%). Others were administered by rubbing on the affected/infected part and through swallowing (11.01%). Result shows that there was no agreement among informants in materials used for measurement or in unit used. Most informants used cup, spoon, drops and fingers to determine doses and differed doses were reported even for same or similar diseases. Most of the remedies were reported to have no adverse effects except for some species, such as Phytolacca dodecandra L ‘Herit., Justicia schimperiana (Hochst. ex Nees) T. Anders., Clematis simensis Fresen. and Solanum marginatum L.f. that were indicated to be poisonous both to human and livestock. Milk, honey, yoghurt and butter were the commonly reported antidotes in case of adverse side effects.

The most-preferred plants for treating human ailments

The output of preference ranking exercise on medicinal plants that were reported to be used against febrile illness revealed Eucalyptus globulus Labill. as the best-preferred species. Withania somnifera (L.) Dunal and Olea europaea subsp. cuspidata (Wall. ex G. Don) Cif. were also among the most-preferred species ranked 2nd and 3rd, respectively (Table 8).

Table 8 Results of preference ranking of six medicinal plants reported for treatment of febrile illness

Disease categories of the highest ICF values

About eight disease categories were identified from the 50 human ailments reported in the study area. The dermatological diseases category was the one with the highest ICF value (0.98) which was followed by external injuries, bleeding and snake bites (0.92), and gastrointestinal complaints (0.84).

Medicinal plants of the highest fidelity level values

Of the plants used to treat human ailments, the highest fidelity level (96.15%) was recorded for Verbascum sinaiticum Benth., followed by Withania somnifera (89.47%), Eucalyptus globulus (88.24%) and Datura stramonium L. (75.86%). Verbascum sinaiticum and Withania somnifera were reported to be used to treat dermatological and sensory and nervous systems diseases, respectively.

Plant use knowledge comparison between different social groups

Significant differences (p < 0.05) were observed between the average numbers of medicinal plants claimed by men and women informants, informants belonging to age groups below 50 and above 50 years and illiterate and literate informants, and key and general informant categories. Higher averages were calculated for men than women, for older people than younger ones, for illiterate people than literate ones and for key informants than general informants (Table 9). In the study area, it was widely observed that grandparents served as the main source of traditional medical knowledge that commonly transferred their knowledge orally to their eldest son and other trusted family members secretly.

Table 9 Statistical test of significance difference between average numbers of medicinal plants reported by different informant groups

Discussion

Ethnomedicinal knowledge of local communities

The local communities living on the fringe of the Wejig-Mahgo-Waren massif forest have amassed significant knowledge about their natural environment, particularly regarding medicinal plants. This study recorded 52 medicinal plant species, reflecting higher richness compared to areas like the Zay people (33 species) [12], Tanqua-Abergele and Kolla-Tembien (29 species) [13], and Alamata (25 species) [14] and Mekelle town (25 species) [15]. However, the medicinal plant diversity was lower than reports from Kilte Awlaelo (114 species) [16], Ofla (113 species) [17], Asgede Tsimbila (68 species) [18], Atsbi and Adi Keyih (58 species) [19] and Ankober (151 species) [20].

The reliance on traditional medicinal plants underscores their role in fulfilling the primary healthcare needs of local communities, influenced by factors such as cultural significance, economic constraints, accessibility, and perceived efficacy. These findings align with broader observations in Ethiopia, where medicinal plants play a critical role in healthcare systems due to limited access to modern medical facilities [20].

The study highlights the rich ethnomedicinal knowledge of the local communities near the Wejig-Mahgo-Waren Massif Forest. The comparative analysis with the Ethiopian ethnobotanical database reveals both shared and unique medicinal plant uses across different regions. For instance, the widespread use of Eucalyptus globulus for febrile illnesses aligns with findings from other Ethiopian studies, while the unique use of Verbascum sinaiticum for dermatological conditions underscores the localized nature of traditional knowledge.

Impact of deforestation and drought

Informants noted a decline in the use of medicinal plants compared to earlier generations, primarily attributed to ongoing deforestation and recurrent droughts. The dominance of shrubs as the primary plant habit in the study area suggests significant ecological transitions, where dry afromontane forests have largely been converted to shrub lands. Similar trends have been documented in other regions of Ethiopia, where shrubs often dominate degraded landscapes [21, 22]. However, contrasting studies in Ethiopia have reported herbs as the dominant growth form in less degraded ecosystems [13, 16, 17, 19].

Therapeutic applications and efficacy

A significant number of medicinal plants were utilized for treating febrile illnesses, with Eucalyptus globulus being the most frequently cited species. This suggests both the prevalence of febrile conditions in the study area and the perceived efficacy of E. globulus in treating such ailments. The preference for leaves in remedy preparation, as opposed to roots, highlights a sustainable harvesting practice that minimizes plant destruction. Previous studies have emphasized the importance of leaf-based remedies in reducing environmental pressure on medicinal plant populations [16–18]. The use of roots in remedies, while reported less frequently in this study, is a notable concern. Excessive root harvesting can threaten species survival, especially for slow-reproducing plants, as corroborated by studies from Ankober [20] and Atsbi [19].

Preparation, measurement, and challenges

Fresh plant materials were predominantly used for remedy preparation, attributed to the belief in higher efficacy due to active ingredients. Additives such as honey, butter, and yogurt were commonly incorporated, reflecting traditional practices observed across Ethiopia [16, 20]. However, inconsistencies in measurement and dosage remain a significant drawback, with adverse effects like vomiting and diarrhea reported by informants. Such challenges underscore the global issue of standardizing traditional medicine practices [5, 16].

Knowledge transmission and generational gaps

The study found that indigenous knowledge is primarily transmitted orally within families, with grandparents serving as the main custodians of this knowledge. However, modern education, urbanization, and declining interest among younger generations pose threats to the continuity of this tradition. This pattern has been similarly observed in other Ethiopian cultural groups [23, 24] and globally [26, 32]. The secrecy surrounding knowledge transfer, often limited to trusted family members, serves as a means of safeguarding both cultural heritage and social respect.

Consensus and informant agreement

The highest informant consensus factor (ICF) values were observed for medicinal plants used to treat dermatological diseases, external injuries, and febrile illnesses. These findings are consistent with other Ethiopian studies, which highlight the high prevalence of these ailments in rural communities [10, 20]. The fidelity level (FL) values for Verbascum sinaiticum and Withania somnifera further confirm their significance as key therapeutic plants, warranting further phytochemical and pharmacological investigations [10, 25].

Comparison across social groups

Men demonstrated higher knowledge of medicinal plants than women, which may be linked to traditional practices where sons are often chosen as knowledge heirs [28]. However, contrasting studies have reported no significant gender differences in medicinal plant knowledge [29], while others suggest women, particularly as caregivers, often possess specialized medicinal knowledge [30]. Elderly individuals and key informants held more extensive knowledge compared to younger or general community members, reinforcing concerns about knowledge erosion due to modernization and reduced intergenerational transfer [23, 24, 26].

Comparison between different social groups

The results revealed that men had better medicinal plant knowledge than women and this could probably be due to the reason that boys were usually selected in the study area for the proper transfer of the knowledge.. Other studies conducted elsewhere demonstrated similar results [24, 26, 27]. [28] stated that parents in Ethiopia prefer to pass their traditional medical knowledge more to sons than to daughters. However, a study conducted in other parts of the country demonstrated that there is no significant difference in medicinal plant knowledge between men and women [20, 29]. In contrast, [30] have reported on the presence of more specialized knowledge on medicinal plants with women informants than with men since the former are often called upon to diagnose and treat certain types of diseases.

The significant difference on average number of medicinal plants reported by different age groups compared in this investigation shows that better indigenous knowledge on use of medicinal plants is held by elderly people than by the younger generation. This shows the big gap between generations and which could be resulted in the decline of indigenous knowledge on medicinal plants down the generations. This could partly be attributed to the impact of modernization (including urbanization and advent of formal education), secrecy and oral system of knowledge transfer. The scenario is the same for other cultural groups in Ethiopia [20, 23, 24] and elsewhere in the world [26, 31, 32]. [32] The other significant differences observed in the numbers of reported medicinal plants were between key and general informants which could relate to the impact of age-old experience and maximum degree of secrecy of the former in using medicinal plants, and between literate and illiterate informants which may be related to modernization of the former. Similar results were reported by other authors [20, 23, 24, 28]. According to [30], community members who have greater contact with medicinal plants were more knowledgeable about therapeutic uses of these plants than those with only intermittent contact.

Environmental and Public Health Implications: The reliance on medicinal plants in the study area reflects the limited access to modern healthcare facilities, a common issue in rural Ethiopia. However, the ongoing deforestation and climate change pose significant threats to the availability of these medicinal plants. The dominance of shrubs in the study area suggests ecological degradation, which could further limit the diversity of medicinal plants available for traditional use.

Sustainability and Conservation: The study underscores the need for sustainable harvesting practices, particularly for plants like Clematis simensis, which are used for both human and livestock ailments. The overharvesting of roots, as observed in some cases, could threaten the survival of certain species. Conservation efforts should focus on preserving the biodiversity of the Wejig-Mahgo-Waren Massif Forest while promoting sustainable use of its medicinal plants.

Conclusion

The findings of this study contribute to the broader understanding of ethnobotanical practices in Ethiopia and highlight the importance of cross-cultural comparisons in ethnobotanical research. The conservation and scientific validation of medicinal plants are essential to ensure their continued availability and efficacy for future generations.