Ethnobotanical Study of Medicinal Plants Used against Human Diseases in Zuway Dugda District, Ethiopia

Introduction In Ethiopia, traditional medicine has significantly contributed to the treatment of public health conditions. However, when contrasted with the ethnic diversity of Ethiopians, the number of medicinal plants that have been documented remains limited. As a result, the study aimed to record the medicinal plants used in the Zuway Dugda district communities. Methodology. An ethnobotanical study of medicinal plants used by local people of Zuway Dugda district was carried out from February 2020 to November 2020. Semistructured interviews, a market survey, field observations, and group discussions were used to gather pertinent data. One hundred informants (83 males and 17 females) provided data. 76 informants were chosen at random, while 24 key informants were chosen on the basis of recommendations from local elders. Data were analyzed using descriptive statistics, preference ranking, paired comparison, and direct matrix ranking. Results A total of 73 plant species, representing 62 genera and 40 families, were collected and identified. Asteraceae, Fabaceae, and Solanaceae had the most species, with each family having 6 (8.22%) species, followed by Euphorbiaceae, which had 4 (5.48%) species. The wild harvest of approximately 49 medicinal plants (or 67.12%) was used. 31 plant species, or 42.47% herbs, were found to be the most commonly used life forms. The most frequently used plant parts were reported to be the leaves, which accounted for 55 species (41.35%) and then the roots 25(18.80%). Headache, toothache, depression, febrile illness, and fever had the lowest ICF values (0.33), while snake bite-related issues had the highest ICF values (0.93). The results of the preference ranking indicated that locals prefer to treat wounds with Asparagus africanus Lam. The community used Cordia africana Lam. the most, according to direct matrix ranking. Conclusions It is essential to combine indigenous knowledge with scientific methods in order to extract the most benefit from medicinal plants. The results of the ICF and preference ranking could be used as a prelude to this. Since A. africanus was found to be the most effective wound-healing medicinal plant in the current study, further phytochemical and pharmacological research is recommended.


Introduction
Since the beginning of time, people all over the world have used plants to treat diseases.Plant-based drugs have been developed as a result of some of the fndings from worldwide research to confrm their efectiveness [1].Te use of traditional remedies greatly aided the development of modern drugs.Treatment methods that have been in use for hundreds of years prior to the development and spread of modern medicine make up traditional medicine [2].Te social and cultural traditions of various nations infuence the wide range of these practices.
Exercises, spiritual therapies, manual techniques, and medicines derived from plants, animals, or minerals are all included in traditional medicine [3].Tese practices, approaches, knowledge, and beliefs are used to treat, identify, or prevent illness in addition to maintain health.Traditional healers and plant-based medicines are heavily used in developing countries to treat human diseases.As a result, ethnobotanical studies are useful for capturing, interpreting, and disseminating information about the ways in which human civilizations and plant diversity interact [4,5].
Ethnobotanical studies have been conducted by various scholars worldwide.According to recent evaluations, the number of published ethnobotanical studies is increasing annually, both in Ethiopia [6] and elsewhere in the world [7].Albuquerque et al. [7] claim that additional ethnobotanical research might demonstrate the remarkable advancement of the feld as a science.An impressive number of medicinal plants that are used to treat illnesses in humans and livestock have been gathered as a result of a number of studies that were carried out in various regions of Ethiopia.Megersa and Woldetsadik, for example, found 51 plant species that local people in the Damot Woyde district in southern Ethiopia used to prepare traditional medicines [8].In the Suro Barguda district, 98 diferent medicinal plants were used to treat human ailments [1].Usman et al. [9] and Abdela et al. [10] conducted a similar study and recorded 62 and 112 medicinal plants that were used to treat human diseases, respectively.Te indigenous people of Ethiopia have reportedly used a number of medicinal plants, which suggests that they have extensive knowledge of these plants and their applications [8].
According to these studies, the country's knowledge of medicinal plants is vanishing for a variety of reasons.Indigenous knowledge of medicinal plants is passed down from one generation to the next orally.In this way, the knowledge transfer system may lose fundamental information about how to use plants and their parts, drug preparation techniques, and other things [11].Te primary threats to medicinal plants in Ethiopia were also identifed as the expansion of modern education, religion, agricultural expansion, urbanization, overexploitation, and frewood collection.Local people of Ethiopia had the knowledge of conserving medicinal plants though many authors reported the efort is minimal.Te Guji Oromo has their belief (Waaqefannaa) which has a positive contribution to medicinal plants management.In this indigenous belief, cutting big trees is out of forbidden, because when it falls, it has a very huge sound and power which would disturb God (Waaqa) and all humans closer to the area as well [1].Te study conducted in Wayu Tuka district showed that local healers do not conserve medicinal plants very well, and they preferred to collect them from wild stands when patients visit them.Local people conserve medicinal plants of the public domain in home gardens where Ocimum urticifolium hort.ex Benth and Ruta chalepensis L. are among the frequently grown medicinal plants [11].Te local people of Asagirt district use some methods to conserve and protect medicinal plant species.Te highest conservation method recommended by the local people was home gardens, followed by plantation in mosques and churches [12].
Taking into account the diverse cultures, ethnicities, types of vegetation, and climate zones, the country has very little documented ethnobotanical information about medicinal plants.Te Zuway Dugda district in Oromia is one of the areas that receive less attention.Hence, the aim of the present study was to document the medicinal plants and associated knowledge of the communities in Zuway Dugda district and the threats currently afecting medicinal plants.Te specifc goals of the study were to evaluate how the district's local communities conserve medicinal plants for use in the treatment of human diseases.

Description of the Study Area.
Zuway Dugda district is situated at 7 °44″N and 8 °16″ N and 38 °50″ E and 39 °8″ E. It is located at about 156 km south east of Addis Ababa, in East Arsi Zone of Oromia Regional state Ethiopia.Te district's capital, Ogolcho, is approximately 46 kilometers away in Zonal Capital Asella (Figure 1).

Topography.
Te altitude of the district ranges from 1600 to 1800 meters above sea level and the district has various topographic features, 65% (53,388,615 ha) of the land areas is plain, 15% (12,320,449 ha) hilly areas, and clifs and valleys account 12% (9,856,359 ha) and 8% (6,570,906 ha), respectively [13].

Climate.
According to Zuway Dugda district administration ofce [13], the climate of the area is classifed traditionally into two main agroclimate zones; "Baddadaree (Woina dega) and Gammojjii" (Kola).Te total land mass of the district, about 89.65% (73,635,222 ha) fall under "Gammojjii" while 10.35% (8,501,111 ha) is categorized under, "Baddadaree" (Woina dega).Te rainy season (winter) is traditionally called, "Ganna" and dry season (summer) is, Bona "Ganna" (rainy season) is extends from June to August with the highest peak in July and August.Te highest monthly rainfall in July and the lowest May.Te maximum mean temperature was recorded in February and May (32 °C).Te minimum mean temperature was recorded in October and November (19 °C).In general, the mean annual temperature and mean annual rainfall of the Zuway Dugda district is (21.3 °C) and (732 mm), respectively (Figure 2).

Population.
Te population of the Zuway Dugda district in 2023 projected to be 175,208 according to CSA [14], with 49.7% (87,145) of those people being male and 50.2% (88,063) being female.Te Oromo people make up the majority of the community in the district.Afan Oromo is a widely spoken language in the district.

Educational and Health Services.
Tere are three nongovernmental kindergarten schools in the district [15].Te district also has six frst-cycle elementary schools (ages 1-4), 39 second-cycle elementary schools (ages 5-8), fve secondary schools (grades 9-12), and one private high school.However, the district only has one government school for technical and vocational education.
Tere are thirteen health posts, six governmental health centers, and four nongovernmental clinics [16].In general, the district's health issues are connected, either directly or indirectly, to issues with sanitation, poor diet, a lack of potable water, and poor house condition.In this region, high fever is a common symptom of acute febrile illness, whose cause is unknown.Te most prevalent human diseases in the district are acute febrile illness, upper respiratory tract infection, pneumonia, wound and injury (accident), gastrointestinal tract infection, diarrhea, sexually transmitted diseases, urinary tract infection, skin infection, and joint disease.

Study Sites and Informant Selection
Techniques.Study sites and informants were selected based on the information gathered from Zuway Dugda district administration, health 2 Evidence-Based Complementary and Alternative Medicine and agricultural ofces.Accordingly, six (6) kebeles (the smallest administrative unit), namely, Kiyansho, Unisheti, Arba chefe, Genale, Chefe jile, and Areta cufa were selected from a total of 30 kebeles for data collection with purposive sampling method based on their agroecological conditions, recommendations of local elders, the availability of traditional medicine practitioners, and vegetation cover.Kiyansho, Genale, Chefe jile, and Unisheti were selected from low land agro climatic zones and Arba chefe and Areta cufa from midland.From the six selected kebeles, a total of 100 informants (83 males and 17 females) were selected randomly.
Based on the information they provided during an interview, 24 key informants (22 males and 2 females) were selected.Each of the sampled Kebele health ofcers, local authorities, and knowledgeable elders provided information about healers who were also considered as a key informant.Evidence-Based Complementary and Alternative Medicine 2.7.Ethnobotanical Data Collection.Ethnobotanical data were collected from February 2, 2020 to November 2, 2020 through semistructured interviews, guided feld walks, observations, and focus group discussions (Figure 3).Te semistructured interviews were conducted using Englishlanguage questions that had been translated into Afan Oromo.Te items of the interview are based on the informants' gender, age, occupation, educational level, religion, and category (healer or general informant).Te uses of medicinal plants, which include local names, diseases treated, parts used, preparation methods, administration routes, dosage, habitats, and how local people conserve medicinal plants, are also included in the list of questions.Guided feld walks were conducted with interviewees and other local indigenous people to look for additional wild medicinal plants and gather specimens for vouchers.All interviews were conducted in the Afan Oromo language, which is spoken by the people who live in the area under study.

Market Surveys.
In Chefe Jila and Ogolcho towns, two markets, Jila and Abura, were chosen for the current study (Figure 4).In order to record the names of the medicinal plants, prices, and other aspects of herbal medicines sold in the local markets of the study area, market surveys were conducted.In accordance with the recommendations outlined by Martin [4] and Alexiades [17], observations in the two markets and interviews regarding aspects of wild plant products were carried out in order to identify the medicinal plants that are sold in the market.

Voucher Specimen Collection and Identifcation.
During a guided feld walk, the voucher specimens were collected, and the plants were numbered, pressed, and dried for identifcation.Specimens were identifed both in the feld and in the Madda Walabu University mini herbarium.In addition, various Ethiopian and Eritrean foras were used in the identifcation process [18][19][20][21][22][23][24].

Data Analysis
2.8.1.Descriptive Statistics.Te information on medicinal plants, use, and related knowledge was analyzed and summarized using a descriptive statistical approach, such as percentage and frequency.Descriptive statistics were used to examine the most important information on medicinal plants that locals reported, including the most frequently used plants, medicinal value, application, methods of preparation, route of application, diseases treated, and parts utilized and habits.For analysis, a Microsoft Excel spread sheet was employed.MS Excel spread sheet was used for analysis.

Informant Consensus Factor.
Te diseases of the study area were grouped into various categories based on the site of occurrence of the disease, condition of the disease, and treatment resemblance of the disease to the local people.In order to evaluate the reliability of information during the interview, informants are contact at least two times for the same ideas and the validity of the information is proving and record.Only the relevant ones are analyzed.Te informant consensus factor (ICF) was calculated for each category to identify the agreements of the informants on the reported cures for the group of ailments.Te ICF was calculated as follows: number of use citations in each category (nur) minus the number of species used (nt), divided by the number of use citations in each category minus one [25].Te factor provides a range of 0-1, where a high value acts as a good indicator for a high rate of informant consensus.Here, ICF is informant consensus factor.ICF � ur is number of use citation, n t is number of species used. (1) 2.8.3.Preference Ranking.Following Martin [4], a preference ranking was computed for the eight most important medicinal plants used to heal wounds.Ten of the key informants were shown these plants with the goal of getting their own preferences for the best recommended therapeutic herbs.Te medical plant thought to be most capable of curing the ailment has the greatest value (fve), while the one thought to be least capable has the lowest value (1).Each species' value was added together, and each species' ranking was established using the overall score.

Paired Comparison.
A pairwise comparison method was used to determine the relative importance of plant species, where items were presented in pairs and decisions were made by individual respondents about the relative importance of one of the items in the pair [4].Based on Martin's recommendations [4], a pairwise comparison of the  Evidence-Based Complementary and Alternative Medicine popularity of fve medicinal plant species used to treat febrile illnesses was calculated.Tus, seven key informants were randomly selected by coin toss to independently demonstrate answers to fve pairs of traditional medicinal plants known to treat febrile illnesses.A list of pairs of selected items containing all possible combinations is created, the order of the pairs and the order within each pair are randomized, and then, each pair is presented to the selected informant and the responses were recorded.Total scores are summarized and ranked.Te total number of possible pairs (10) was obtained by applying the following formula: , where n is the number of items. (2) 2.8.5.Direct Matrix Ranking.A direct matrix ranking was performed to compare the multipurpose medicinal plants commonly reported by informants after cotton [26].Based on the relative benefts obtained from each plant, six multipurpose tree species across medicinal plants and seven uses for these plants are listed.To assign a use score to each attribute (5 = best, 4 = very good, 3 = good, 2 = less used, 1 = least used, and 0 = less used), ten key informants were selected.Based on information gathered from informants, average values for each use of the species were obtained and the values for each species were summed and ranked.1).Of the medicinal plants used for human diseases, 49 (67.12%)species were collected from wild vegetation and 24 (32.88%)species were collected from home gardens.

Growth Form and Plant Parts Used to Treat Human
Diseases.A growth habit analysis of medicinal plants showed that 31 species (42.47%) of herbs represented the highest percentage, while shrubs represented by 23 species (31.51%) (Figure 5).Regarding plant parts used, 55 (41.35%) were leaves and 25 were roots, accounting for 18.8%, which were mainly used to treat human diseases (Figure 6).

Conditions of Preparation, Dosage, and Route of Administration.
Local people in the study area prepare herbal remedies for various ailments, and medicinal plants are available fresh, dried, or fresh and dried.It was reported that approximately 59.4% were used in fresh form, 35.34% were made from dried plant parts, and 5.26% were made from both dried and fresh plant parts.Among the collected medicinal plants, preparations were mainly used in the study area, mainly single and diferent types of plant parts.Of the two diferent formulations used by local populations Evidence-Based Complementary and Alternative Medicine in the study area, 84.96% were associated with a single plant species and 15.04% were associated with diferent plant species.
Local people of the study area used diferent units of measure and dosing durations to determine dosage.Local units such as fnger length for (bark, root, stem, etc.), various measuring materials (spoon, cofee cup, teacup, glass cup, etc.), and numbers (leaves, seeds, fruits, tubers, rhizomes, fowers, latex, etc.) were used to estimate and correct the dose of the drug.However, these measurements are not precise enough to determine exact doses.Remedies were administered without exact dosages, but locals used traditional units of measurement, such as spoons, cofee cups, teacups, counts or numbers, tin can, and glasses to determine dosage particularly taken through mouth, nose, ears, and eyes.
Local people in the study area were administered traditional medicine mainly orally.Oral accounts for 63.91%, followed by dermal (23.31%), nasal (10.53%), and other (2.25%) (Table 2).Locals also reported that various additives were administered when administering traditional medicines.Te remedies were taken with cofee, milk, honey, water, salt, tea, red tef powder, sugar, oil, and butter.

Transfer of Knowledge on Medicinal Plants.
Ethnomedicinal knowledge is concentrated among elders and their relatives in the community and is difcult to transfer the knowledge from older to younger generations.Te informants of the current study who were interviewed indicated that they obtained their knowledge of medicinal plants from a variety of sources, mostly from family (71%), relatives and friends (10%), and others got it from a healer (4%) through the transfer of specifc knowledge about medicinal plants.Knowledge of the identifcation and handling of medicines with the ingredients used and ecology is mainly related to oral knowledge transfer by locals and the elderly.Oral transmission of knowledge about such medicinal plants is declining and knowledge about medicinal plants is disappearing.Indigenous knowledge of medicinal plants encountered problems in passing on this knowledge and the practice of traditional medicine, according to informants, as younger generations were unwilling to acquire knowledge of traditional medicinal plants.

Informant Consensus.
Of the 73 medicinal plants collected in the study area, the use of some medicinal plants to treat human diseases was frequently reported, while the use of others was less reported.Among the medicinal plants reported in the study area, Ocimum lamiifolium Hochst.was named by 57 respondents, followed by Aloe pubescens Reynolds, 54 respondents named the plant species (Table 3).6 Evidence-Based Complementary and Alternative Medicine

Evidence-Based Complementary and Alternative Medicine
Informant Consensus Factor (ICF).Diseases in the study area were grouped into diferent categories based on the location of disease occurrence, disease status, and similarity of disease treatment to local populations.Medicinal plants believed to be efective in treating specifc ailments had higher ICF scores, indicating that these ailments were more common than those with lower ICF (Table 4).Snake bites had the highest ICF value (0.93) in the study area due to disease incidences.Depression, febrile illness, fever, headache, and toothache (0.33) had the lowest ICF scores in the study area.

Preference Ranking.
Wound was one of the most common diseases in the study area.Eight medicinal plants have been described as efective in treating wounds, and ten leading informants ranked these eight plant species based on their perception of their level of efectiveness.Tus, A. africanus was the most preferred medicinal plant for wound healing and Solanum marginatum L.f. was the least preferred medicinal plant (Table 5).

Paired Comparison.
For medicinal plants identifed by informants to treat febrile illnesses, paired comparison between fve medicinal plants was performed.Seven key informants participated in this activity.Hence, O. lamiifolium ranked frst, followed by B. aegyptiaca, and the least preferred medicinal plant for treating febrile diseases was Cynoglossum lanceolatum B.Heyne ex Wall (Table 6).

Direct Matrix Ranking.
In the study area, plant species with multiple uses were studied.Key informants selected 10 plant species with multiple uses.Common uses include medicine, frewood, charcoal, construction, fencing, and edibles.Tis fnding indicates that C. africana ranked frst for its multiple uses, followed by Olea europaea subsp.Cuspidata (Walland G.Don) Cif.; on the other hand, Carica papaya L. came last and was the least frequently used in the study area (Table 7).

Marketable Medicinal Plants.
As explained by the respondents, traditional medicines prepared by healers from plants or parts of plants are sold at home rather than on the open market due to the preference of local people.Medicinal plants marketed on the open market as a spice for nonmedicinal purposes A. sativum, A. cepa, Artemisia abyssinica Sch.Bip., Capsicum annuum L., Coriandrum sativum L., Lepidium sativum L., Nigella sativa L., O. basilicum, Trigonella foenum-graecum L., and Zingiber ofcinale Roscoe, food (Brassica carinata A.Braun, B. nigra (L.) K.Koch, Cucurbita pepo L. and L. usitatissimum, C. papaya and Citrus limon (L.) Osbeck).

Treat and Conservation of Medicinal Plants of Study Area
(1) Treat of Medicinal Plants.Agricultural expansion, charcoal production, construction, and frewood collection were common threats to medicinal plants.Informants ranked agricultural expansion (19.13%) as the most common threat to medicinal plants, followed by charcoal production (18.7%) (Table 8).
(2) Conservation of Medicinal Plants.Eforts to conserve medicinal plants within the district were classifed as low.Some traditional practitioners have begun to grow medicinal plants in home gardens, but their eforts have been minimal.Medicinal plants grown in home gardens include A. cepa, Daucus carota L. and A. cepa, V. abyssinica, C. annum, L. sativum, R. chalepensis L., Cymbopogon citratus (DC.)Stapf, and Rhamnus prinoides L'Her.

Medicinal Plants of the Study Area.
A total of 73 medicinal plants belonging to 62 genera and 40 families were reported to be used for the treatment of human diseases by local informants in the study area.Te number of medicinal plants reported and their use by the local population of the area shows the depth of local indigenous knowledge of medicinal plants and their uses.Te knowledge and practice of a large number of medicinal plants by the people of the Zuway Duguda district shows that the indigenous people of the study area still rely on traditional medicines derived from plants.Asteraceae, Fabaceae, and Solanaceae are the most commonly reported medicinal plants.Fabaceae has also been described as a major medicinal family in ethnobotanical studies elsewhere in Ethiopia [1,27,28].Similar studies reported Asteraceae as the major family in Ethiopia [8,12,29,30], and Solanaceae was mentioned in the work of Mesfn et al. [31].In contrast, other studies found Lamiacae [32] and Euphorbiaceae [33] to be dominant over others.Two families (Asteraceae and Fabaceae) are most common in the Ethiopian fower region.In addition, the Asteraceae is dominant because its members are known for their scent properties and are widespread in nature.Tis dominance may be due to the herbaceous lifestyle of the family.Te fndings are reasonable since the mentioned families are represented by higher number of species in the Ethiopian fora.Te majority of medicinal plant species obtained from wild habitats.Of the 73 medicinal plants collected, majority were obtained from the wild.Te results indicate that communities tend to rely more on wild-collected medicinal plants than on home gardens.Our results are consistent with the general pattern reported in many ethnobotanical studies conducted in Ethiopia [9,10,34,35] and elsewhere in the world [36,37].Tese fndings call for the urgent need of medicinal plants conservation in home gardens or by other approaches.

Growth Form and Plant Parts Used.
Te most common herbal remedies used by the people of the Zuway Dugda district were derived from herbs.Te report indicates that herb use was easy and accessible, as the herb grows primarily on roadsides and in home gardens at the study site.Similar results were reported by previous ethnobotanical studies [10,[37][38][39].In contrast, other studies have found shrubs to predominate in traditional medicine preparations [1,40,41].Te shrub dominance, as shown by Eshete and Molla [1], may be due to the high prevalence and impact resistance of shrubs in the study area.
In terms of parts of use, leaves were the most commonly used for treatment within the study area compared to other parts.Our results were consistent with previous studies reporting leaves as a major medicinal plant part in various other study areas [29,34,37,42].Given the most abundant leaves used for medicinal purposes in the study area, the risk of destroying medicinal plants was considered minimal.Te reason for the frequent use of leaves may lie in their function as centers of photosynthesis and other metabolic activities, thus most secondary metabolites are formed in leaves [43].In addition, leaves are considered the simplest and most accessible part of the plant for medicinal preparations, rather than other parts of the plant [37].Other studies on aspects of ethnobotany have shown that the root is the most commonly harvested part of the plant used to make traditional medicines [33,36,44].Te use of root for traditional medicine preparation may have a detrimental impact on plant species and thus a wise approach of collection or conservation of such medicinal plants is vital.Evidence-Based Complementary and Alternative Medicine Most traditional medicines are primarily from single plants or plant parts.Tis fnding is similar to others reported in Ethiopia [39,45].Other similar studies have reported the use of mixtures of diferent species to treat disease, rather than using a single species [46].Tis difference may be due to diferent sources of information.Te present study was conducted across communities, whereas the previous study was conducted with traditional healers shown to be the most common [11].

Route of Administration and Dosage of Traditional
Medicine.Te most common route of administration was oral followed by dermal.Reports similar to our study showed that oral administration of drugs was common, followed by dermal and nasal administration [1,9,28].In other studies, topical application is an important method of administering herbal medicines used to treat various external diseases [37].For this reason, oral and dermal administration allows rapid physiological responses between prepared drugs and pathogens, enhancing their therapeutic potential [47].Tis may be because the two pathways are more efective, as the prepared drug reacts quickly with the pathogen's physiology and enhances its healing power [39].Frequent occurrences of internal disease in the study area may also be a further indication.
Regarding doses, local people in the study area used a variety of units of measurement, including cofee cup, fngertip, teaspoon, glass, and palm.Traditional units of measurement such as spoons, cofee cups, teacups, counts or numbers, tin cans, and glass cups are commonly used to determine dosage.In a similar study, Eshete and Molla [1] reported that dosages prescribed for various ailments are based on patient age, sex, and physical appearance.Tis indicates that there is no standardized measurement, except that it is determined based on the long experience of traditional healers [1].Similar approaches have been reported in diferent parts of the country [32,39].Lack of precise dosage is known to be a major drawback of using traditional medicine [48].Tis discrepancy could cause problems for patients due to overdose efects.However, as reported by Megersa and Tamrat, local healers give various additives as antidotes to side efects [32].

Informant Consensus Factor (ICF).
Te results of the study showed that common diseases in the study area had higher informant consensus factors.Snakebite had the highest ICF score, followed by fever and headache, due to the high incidence of illness in this region.Te highest calculated ICF value indicates the best agreement among informants regarding the use of a medicinal plant species to treat a particular disease [39].High ICF values are important for naming plants of particular interest when searching for bioactive compounds [49].In addition, plants achieving higher informant consensus scores were thought to exhibit better efcacy when the treatment included a biologically active ingredient compared to plants with lower informant consensus scores.Diferent results have been reported by researchers in diferent parts of the world.Tus, the highest ICF value for bone and joint disease was recorded in Rif, northern Morocco [42], and gastrointestinal disease recorded his highest ICF value reported by Eshete and Molla in Suro Barguda district, Ethiopia [1].Te diference of fndings among studies could be due to the diference in the prevalence of diseases in the study areas.

Preference Ranking.
When there are diferent species prescribed for the same health problem, people show preference for one over the other.Te analysis of preference ranking exercise on medicinal plants that were reported to be used against wounds showed that A. africanus was the most preferred species followed by D. viscosa.Tis fnding showed that wound was most frequently reported human disease in the district.Similar studies conducted by Jima and Megersa [33] in Berbere district reported diferent medicinal plants used for wound treatment.Tis fnding may show as the medicinal plant knowledge varies among diferent communities and also show the importance of such studies to discover a modern drug for diseases.

Direct Matrix Ranking. Direct matrix ranking results
showed that C. africana ranked is a versatile plant species.Te results of Megersa et al. [11] showed C. africana as the highest multipurpose species in the Wayu Tuka district, West Wellega Zone of Oromia, Western Ethiopia, and Goro district Bale Zone of Oromia [9].Local communities in the Hulet Eju Enese district also use C. africana for various purposes [41].On the other hand, various plant species have been reported to rank among the highest for multi-purpose use in various communities in Ethiopia.For example, O. europaea subsp.cuspidata has been described as the best plant species used for various purposes in communities of Sedie Muja district [39], Prunus africana (Hook.f.) Kalkman [1] in Suro Barguda district.A wide range of plant species are  [34].For example, C. africana is endangered due to its multiple uses, as evidenced by its sparse distribution in various regions of Ethiopia [11,31].Terefore, it is attracting attention as a native tree species.Conservation priority is therefore given by using domestic in situ and ex situ conservation [50].Additional conservation measures are urgently needed to prevent future extinctions of other reported multipurpose plant species [51].

Conclusions
Our results indicate that plant species play an important role in the treatment of various human diseases in the Zuway Dugda district of Ethiopia.As a result of this study, 73 medicinal plant species were recorded.Asteraceae, Fabaceae, and Solanaceae are the three families with the highest percentage of medicinal plants in the study area.Te number of medicinal plant species recorded in the study area is a good indicator of the potential of medicinal plants for the development of modern medicines.To get the most out of medicinal plants, it is essential to implement indigenous knowledge in a scientifc way.For this, the ICF and preference ranking results can be used as precursors.In the present study, A. africanus was the most preferred medicinal plant for treating wounds.Terefore, it is recommended to conduct phytochemical and pharmacological studies to confrm the wound-healing properties of the plant.Medicinal plants in the study area are threatened by various factors, with agricultural expansion accounting for the largest share.Local communities play an important role in preserving medicinal plants around their home gardens, but it is clear that most plant species are where they have been collected from wild habitats.Te efort involved is minimal.Terefore, the focus of conservation should be on the most threatened and preferred medicinal and multipurpose plant species.

Figure 3 :
Figure 3: Group discussion held on threats and conservation to medicinal plants with informants' photo taken by Fikadu, (2020).

Figure 5 :Figure 6 :
Figure 5: Growth forms of medicinal plants in the study area.
smoke of pounded roots is inhaled N L Headache Dried leaf of C. spinarum is pounded and the smoke is used as treatment for headache F L Stomachache Leaf of C. spinarum is pounded mixed with honey.Two-three spoon is taken early in the morning before breakfast O Acokanthera schimperi (A.DC.)Schwein Qaraaruu Sh W F L Leprosy Leaves of this plant are pounded together with B. antidysentetica, Rumex abyssinicus jacq.then mixed with butter and applied on the skin root is pounded together with leaves of D. viscosa, mixed with butter and applied on the wound F L Malaria Leaf is crushed, mixed with milk and taken one cofee cup every morning until the individual goes from the Echinops angustilobus S. Moore Qoree harree H W D/F R Headache Fine root powder is mixed with pounded A. sativum and taken pasted with honey O TN058 Echinops hispidus fresen.Kaabariic hoo H W D R/St Evil eye Crushed and placed on fre and inhaled by all householders Sm TN042Artemisia abyssinica sch.Bip.ex A. Rich Harrittaa H HG F wh Evil eye Leaf concoction together with root of E. kebericho is added to a burning fre and smoked to the patient Sm TN033 Artemisia schimperi Sch.Bip.ex engl.L/F r Fungal on skin Te fruit or leaves of X. strumarium is rubbed and of V. amygdalina concocted with leaves of R. chalepensis.One cup is served as a drink for 3-5 days with cold water in the morning O TN025 Skin infection Leaf of V. amygdalina is pounded and is washed by the plant or the leaf of is used as a soap to wash the infected body D Internal worm Te decocted leaves with 1cup of cofee for elders and half for children, 3leaf together with O. lamiifolium is pounded and drunk with cofee or rub the body with the leaves boiled in water then drunk and the head of the patient is washed with it or smell the plant as it O Heliotropiu m cinerascens steud.ex.DC. of H. cinerascens are extracted water taken into body by one cup of tea or cofee of L. sativum, bulb of A. sativum and rhizome of Z. ofcinale are pounded together and given to of L. sativum and bulb of A. sativum are pounded together and given to human with honey problem Crushed and eaten with A. sativum by adding salt of B. carinata together with seed of R. communis crushed, powdered and mixed with honey and fresh/dry root bark mixed with leaf of C. macrostachyus and water is given as drink fresh root of C. cunninghamiana are mixed in water and the solution is taken fresh young leaf and the bark is pounded, boiled, add butter, cool it and after it solidifes, three nine tablets are made and three tablets for children, fve to nine tablets for elders is given.Milk is drunk as or eleven shoot tips is cut, cooked together with R. chalepensis and one spoonful of the solution is drunk per a day for seven consecutive days O F B Stomachac he Fresh bark together with bulb of A. sativum, is pounded, mixed with butter and eaten O TN04 Euphorbia abyssinica J.F.Gmel.Adaam ii T W F/D L Gonorrhea Very small amount of the milky latex is mixed with red tef four, bake and eaten for three consecutive days O pounded, mixed with small quantity of latex from Aloe spp.And drunk one cofee cup before bed time for disease Latex is mixed with E. tef powder to prepare bread and given crushed, mixed with honey and half teaspoon is eaten for three consecutive days O TN016 V. abyssinica (Hochst.ex Benth.)Kyal. of T. foenum-graecum is mix with water, seed of T. foenum-graecum is crushed, powdered, mixed with honey and little water then boiled like "porridge" and eaten O Salicaceae Dovyalis abyssinica (A.Rich.Wa rb) Kooshi moo Sh W F Fr Intestinal parasites Fruit is eaten as food for the case of intestinal parasite before breakfast leaf of O. lamiifolium together with leaf of E. globulus, is pounded, mixed with water and drunk or inhale the vapor of the boiled mixture the root of W. somnifera are pounded, mixed with water, boil, cool and then drunk O Ajuga integrifolia Buch.Harma gussaa H W D/F L Body swelling Dry or fresh leaves are pounded & drunk or tied chewed and swallow its content, root is crushed, boil and drunk for three days fne powder of the root is mixed with the powder of the leaf of A. africanus and is applied O Oleaceae Olea europaea subsp.cuspidata (Wall.together with dried leaf of Chenopodium myricoides is boiled in water and steam the vapor to root of A. abyssinica, J. schimperiana is pounded, mixed with water; one katicala glass of the solution is given at interval of roots of C. citratus with root of C. macrostachyus are pounded dried put on fre and the smoke is of N. sativa is pounded powdered and added to cofee.Ten drunk for 3cofee bean is mixed with butter and eaten or drunk before breakfast for 3of C. arabica is roasted, pounded, powdered and applied on afected part N D S Spider poison Seed of C. arabica is roasted, powdered, mixed with butter seeds of C. arabica is pounded together with Leaf of T. foenum graecum, mixed with butter and rubbed on the external eye of C. limon is pounded, powdered, mixed with milk and boiled and added sugar then drink pure liquid during pounded together with Z. ofcinale, added to cofee and then a cup of cofee is drunk every morning for three consecutive days leaf together with leaf of D. stramonium is rubbed on the body of the patient or washes with the solution of leaf together W. sominifera and L. tomentosa, are pounded, half spoon is added to a cup of cofee and drunk every morning until leaf is chopped and placed in the nostrils or small amount of the fruit juice is applied through the and seed of C. annuum is pounded, powdered mixed with butter and creamed the infected part D TN053 D Fr/S Tonsillitis Fruit and seed of C. annuum is pounded, powdered, mixed with oil, roasted and drunk O Withania somnifera (L.) Dunal in DC. leaf is squeezed with leaves of R. chalepensis and drunk leaves of U. simensis with the bark of C. macrostachyhus are pounded, powdered, mixed with little water, fltered, then a cup of fltrate is drunk for 5 days in the morning O Verbanaceae Lippia adoensis var.adoensis Hochst.Fresh or dried root together with the dried bark of C. macrostachyus is crushed and eaten after breakfast pounded and boiled and a tea spoon of it is added to cup of cofee and drunk for three days every O Vitaceae Cyphostemma cyphopetalum (Fresen.)Desc.ex wild & R.B.Drumm.fower is squeezed and the juice is applied or the fower is rubbed over the wound fresh of leave is chew and tie on surface part of swelled body O Hb � habit; Pu-part used; Ut � used to treat; Cp � condition of preparation; RA � route of administration; T � tree; H � herb; Sh � shrub; Cl � climber; Hu � human; F � fresh; D � dry; F/D � fresh and dry; O � oral; De � dermal; Na � nasal; Ey � eye; Er � ear; L � leaf; R � root; Sm � smoke; St � stem; Ba � bark; Fl � fower; Fr � fruit; S � seed; Bu � bulb; La � latex; Wp � whole plant; Ht � habitat; HG � home garden; W � wild; VN � voucher number.

Table 1 :
Taxonomic diversity of medicinal plants in Zuway Dugda district.

Table 2 :
List of medicinal plants used to treat human in the study area.

Table 4 :
Informant consensus factor by categories of diseases in the study area.

Table 5 :
Preference ranking of medicinal plants used to treat wound in Zuway Dugda district.

Table 6 :
Paired comparison of medicinal plants used to treat febrile illness (R stands for informants).

Table 8 :
Ranking of medicinal plants reported as threatened in the study area.