Around 500 higher plant species, with around 12 percent endemism, and thus one of Africa's six rich plants biodiversity countries, are believed to have a home in Ethiopia . The genetic diversity of the different biotic make-up is also high, making the country a vital diversity hotspot for plants. Ethiopia has a large portion of two of the world's 25 biodiversity-rich hotspot regions, namely the Eastern Afromontane Biodiversity Hotspot and the Horn of Africa-Biodiversity Hotspot. These hotspots are home to a lot of useful wild biodiversity, especially medicinal plants. Medicinal plants are the oldest known source of healing for both human and livestock diseases.
It is estimated that nearly 6000 plant species with popular therapeutic usage in Africa . About 80% of the people in the country use raw medicinal plants to meet their primary health care needs. This high percentage is due to a variety of factors, including restricted exposure to modern pharmaceutical products, and accessibility.
This research has recorded the distribution of 50 medicinal plants in 26 families used for treating common animal and human diseases. Out of the 26 plant families, Solanaceae (14.3%) was the biggest contributor, followed by Asteraceae and Poaceae (10.2%) and Euphorbiaceae (8.16%). Solanaceae are considered to have a wide variety of alkaloids. Therapeutic, these are the most potent known anticholinergic species used for medicinal purposes in the world. The Solanaceae family is characteristically ethnobotanical, which is commonly used by humans. It is an essential source of food, spice, and medicine and is also recorded for insecticidal properties .
In the report, Asteraceae and Poaceae were the second dominant families in human health care. However, other ethnobotanical researchers   considered Asteraceae to be dominant in their field of study. This can be attributed to the geographical location, the social condition, and other cultural causes of local communities. The degree of ethnobotanical exploration in their areas of study may be a further explanation, or the entire region may not have been explored thoroughly.
In the field of research, most plants have been used for treating human and livestock diseases. Among the 50 medicinal plants, 41 species were used for the treatment of 27 human ailments, whereas one species was used to treat one livestock ailments. The other eight species were used for the treatment of four common human and livestock diseases. Many medicinal plants have been used to treat a greater proportion of human diseases than animals because of human diseases such as stomachache, snake biting, cough, malaria, wound, ‘mitch’, and toothache. The rural population in the study area due to its socio-economic situation, the distance from its living area, and a lack of road infrastructure are not readily accessible for modern medical facilities. Abebe  and Hostettmann and Marston  have stated that 80% of people in the country are still using herbal remedies for various problems. Similar results from their study sites have been recorded in Ethiopia by many researchers   . Medicinal plants are often gathered from the wild by the healers in the study field. Most ethnomedicinal plants come from wild areas  .
The medicinal plants in the study area had diverse growth forms; in this case, herbs were the dominant growth form. Similarly, Chama , Giday et al. , Hailemariam et al. , and Lulekal et al.  reported that most medicinal plants were herbs in Damot Gale, Sheko, Konta and Ankober districts, respectively. In contrast, the majority of medicinal plants were shrubs in the south Omo and Mana Angetu , . Regassa , in Hawassa city, indicated that the majority of the collected medicinal plants there were trees.
The results showed here that leaves were the most commonly used component, contributing rather than harvesting a root and/or whole plant to the conservation of plants. In the same way, Hailemariam et al. , Giday et al. , and Chama  reported leaves as the predominant plant part used in their study site. In contrast, the most frequently used plant parts were roots in the Hadiya zone  and in Benna-Tsemaye . Lulekal et al.  and Tolossa et al.  also noted roots were the most commonly used plant part in a study focusing on Mana Angetu district and south Omo, respectively.
The local people in the Diguna Fango district use different remedy preparation process based on the type of disease to be treated. Eating, chewing, grinding, squeezing, drinking, smelling, powdering, painting, boiling, hold on, and spitting were some of the preparation methods used to treat human and livestock diseases. In this survey, eating and chewing were the most widely used process. Apart from Diguna Fango, the most widely used remedy preparation methods have also been identified in similar findings   . These were grinding, followed by chewing, boiling, eating, and in liquid form.
The remedies prepared have been administered in various ways. Some of the administrative routes have been oral, dermal, and nasal. In the present region, most remedies have been administered orally and the dermal and nasal routes have been followed. In various parts of Ethiopia, similar findings have also been reported. In the district of Damot Woyde the majority of medicinal plants were given orally . Tolossa et al.  reported that the majority of plants were used in oral applications in the south Omo. Tolossa and Megersa  found that prepared remedies were widely administered orally in Berbere district, Bale zone of Oromia Regional State.
In the study area, the diseases affecting both humans and livestock were 28 in number. This indicated that the people of the district suffered from fewer ailments as compared to those in other areas, such as in the Berbere district, Tolossa and Megersa , Damot Gale district,  and the south Omo . Moreover, a single human ailment found to be treatable by several medicinal plants. This is in agreement with the findings of earlier studies , ,  that found a single disease to be treated by several medicinal plants. The present study found that 22.58% of medicinal plants were used to treat gastrointestinal diseases, with slightly lower rates for dermatological infections/diseases (12.9%). Similarly, among the south Omo people, 24.2% of medicinal plants were used to treat gastrointestinal complaints .
On average, the number of medicinal plants was substantially higher for informants under the age of 20 years than for informants above 35 years and by illiterate informants than literate ones. This may be due to the influence of modernization and a lack of interest among younger generations in botanical medicines that would contribute to the conventional knowledge of older people. Similar conclusions also show that there are substantial gaps between different age groups in traditional knowledge . Unlike the study now underway, the literary young people Tefera and Kim  have a higher level of knowledge in the use of medicinal plants than analphabets and old people.
For gastrointestinal disorders, the highest citation was found, followed by Fever. Similarly, the most frequently treated diseases in Hawassa  and South Omo  were gastrointestinal disorder and parasite infection. Furthermore, a study conducted in the Ethiopian community Sheko revealed that the widely treated diseases were skin and gastrointestinal problems . In Berta, the ethnic group of Benishangul-Gumuz, diarrhea was a widely treated disease . The disparity may be influenced by the climate, ethnicity, and hygiene variations in the regions.
The highest-fidelity levels (100%) were found for Croton macrostachyus, Pentas spp., Triticumdicoccon, and Commelinabenghalensis in the current study. The first two species were in the skeletomuscular system disorders categories and the following two species were in endocrine/metabolic/nutritional and dermatological infections/diseases categories, respectively. The category with the highest ICF values was cardiovascular system diseases, followed by Fever (Malaria). Similarly, the category with the highest ICF values was fever (malaria), followed by insects and ectoparasites diseases in Hawassa zuria district . Regassa  reported stomachache had high degrees of ICF and that malaria showed the highest FL in Hawassa city.
The highest informant consensus value was found for Triticum dicoccon (Schrank) which was cited by 60 respondents for treatment of bone fractures and weight gain. Medicinal plants with higher informant consensus need to be seriously considered for further ethnopharmacological studies since they are species widely applied by many people and they have been utilized for a long time .
The output of the preference ranking indicated that Hageniaabyssinica (Bruce ex Steud.) J.F.Gmel., Rutachalepensis L., and Solanumincanum L. were the most commonly preferred medicinal plants as treatment for stomachache in humans in the study area. Similar findings for south Omo showed that the highest numbers of plant species were reported to treat abdominal or stomach disorders . Acaciaabyssinica Benth, Syzygiumguineense subsp. Macrocarpum (Engl.) F. White and Eucalyptusglobulus Labill, were ranked as the most threatened medicinal plants of the study area.
According to the direct matrix ranking results, Perseaamericana Mill, was ranked first as the most preferred medicinal plant used for various purposes by the local people. The second and third most preferable medicinal plants were Acaciaabyssinica Benth. and Eucalyptusglobulus Labill., respectively. However, Prunusafricanus is the most preferred medicinal plant for various uses in the Hadiya zone . Crotonmacrostachyus is the most multipurpose medicinal plant in the Berbere district of the Bale zone . In the present study, Perseaamericana Mill. was used as a type of food, as fodder, as cash crop, in house construction, and sometimes in charcoal making.
According to the responses from informants, the main causes of the loss of medicinal plants in the study area were charcoal production following agricultural expansion, firewood, household construction and furniture making, deforestation, secrecy, unwillingness of the young generation, oral-based knowledge transfer, lack of awareness and environmental degradation. Similar results were found in other research concerning threats to medicinal plants in Berbere district , Damot Gale , and south Omo . In order to maintain the indigenous knowledge and prevent the extinction of medicinal plant resources, greater conservation understanding of all members of the society is required.
Comparison with previous ethnobotanical studies
Allium sativum L. and Vernonia amygdalina, Sch. Bip., were the most frequently used plant for stomachache, malaria, wound, evil eye, and cough in the present study, and similarly, Chama  reported this plant use for malaria in Damot Woyde district. Giday etal.  reported for headache treatment in Sheko and for evil eye Wubetu . Coffeearabica L. was the most frequently used plant for headaches and wound in the present study. These findings also agreed with the study conducted in the Sheko district  and Guba Lafto district . The plant in the present study for the treatment of wounds is reported for the first time.
Capsicum annuum L. and Capsicum frutescens L. were the most commonly used medicinal plants as a treatment for headache in the present study. Similar findings for Sheko people showed that the plants were reported to treat headache . Aloe vera was reported in the present study for the treatment of malaria, diabetes, and wound. The previous studies conducted in other areas mentioned the use of Aloe spp. for cold and malaria treatment in Kembata  and Damot Woyde district .
Zingiber officinale and Rhamnus prinoides was the most frequently used plant and reported to be used against tonsillitis and cough in our study. Similarly, Chama  mentioned these plants are used for tonsillitis and cough. Triticumdicoccon (Schrank) Schübl, Linumusitatissimum L. and Hordeumvulgare L. were used to treat bone fractures; weight gain, liver disease, and bone strength in the present study, whereas it is used for similar purpose in other study areas .
Moringa stenopetala (Bakerf.) Cufod was documented for amoeba, hypertension, malaria, asthma treatment in the current study. Hailemariam et al.  and Tefera and Kim  reported this plant use for similar health problems from Konta special woreda and Hawassa zuria district, respectively.
Citrus aurantiifolia (Christm.) Swingle, Datura stramonium L. and Dovyalis abyssinica (A. Rich.), were reported for the first time to be used for toothache treatment in the present study. However, Citrus aurantiifolia (Christ) was mentioned by Tefera and Kim  for their area of study in order to treat gastritis and hypertension. Soni etal.  indicated the treatment of stomach and intestinal pain that results from worm infestation, toothache, and fever from inflammation by using Datura stramonium L. Tuasha et al.  reported Dovyalis abyssinica (A. Rich.) for treat of malignancies in Dalle district.
Nigella sativa L. was used for stomachache in the present study. Similarly, this plant was reported for stomachache and headache in Hawassa city . Others reported it for common cold, asthma, leprosy, and streptothricosis  and . Capsicum annum L. and Carica papaya L. reported in the present study for the treatment of gastritis were supported by Amsalu etal.  and Maji and Banerji . According to Amsalu etal. , these plants are used for the treatment of dysentery and vomiting.
Croton macrostachyus Hochst. ex Delile and Euphorbia abyssinica were reported for swelling and headache treatment in the current study. Amsalu et al.  and Abera  reported these plants for gastrointestinal disease and rabies. However, in line with the present finding Tefera and kim  reported Euphorbia abyssinica for treatment of swelling, gastritis, malaria, and headache. Citrus aurantiifolia (Christm.) Swingle reported in the present study for the treatment of motion sickness. Similarly, Mohsenzadeh etal.  mentioned this plant for motion sickness treatment. Another study mentioned Cordiaafricana Lam. as a good treatment for motion sickness .
Artemisia abyssinica Sch. Bip. ex. Rich and Ruta chalepensis L. were the most frequently used plant for evil eye and stomachache in the present study. This finding agrees with the finding of Chama  and disagrees with the finding of Giday etal.  conducted in other areas which stated the plant use for headache and cold.
According to the comparison of our findings with others ethnobotanical studies in Ethiopia, novel plant uses of some medicinal plants were documented. Commelina benghalensis L., Manihotesculenta Crantz., Pentas spp., Persea americana Mill., Solanummacrocarpon L., Sorghumbicolor (L.) Moench and Spilanthesmauritiana DC. were completely novel use in our study area and never ever reported in other similar investigations. The pharmacological activities of these plants are novel findings that are only known in this area for such medicinal purposes.
Dosages of herbal remedies
There is no standardization of the dosage of herbal remedies in the study area; the sum depends on the herbalist who prepares the herbs for medicine. The same plant species with a specific part are recommended in different doses for the treatment of related conditions. Various reports consider the lack of standardization and quality control one of the key disadvantages of traditional medicine. There remains no consensus among informants on the doses and inadequate dosage accuracy of certain prescription remedies .
Several authors recall that a restriction on traditional medicinal plants is the lack of an appropriate dosage for a specific disease. The dosage also varies between the plants  . The toxicity and harm potential of some medicinal plants are a common concern for people who want standardization in conventional medicine. Traditional practitioners are usually believed to either disregard the strengths of the drugs themselves or to not bother to match doses to patients' size or bodyweight . However, some traditional healers are known to prescribe various dosages and frequencies according to age, gender, and other conditions or to vary from one medicine to the other.
Medicinal plants trade and cultivation
Commercialization and marketing of medicinal plants shall take place on the market on a weekly or biweekly. The fresh and dried collections of some plants is sold were Artemisia afra, Ruta chalepensis, Linum usitatissimum L., Lippia adoensis Hochst., Ocimumgratissimum L., Triticum dicoccon (Schrank) Schübl, Hordeum vulgare L., Avena sativa L. and all Capsicum spps. In addition, parts of different medicinal plants are also marketed for their medicinal value (Allium sativum, Lepidium sativum, Nigella sativa, and Zingiber officinale Rosc). Drugs using indigenous medicine are the cheapest and mostly the only available form of healthcare in rural areas of Ethiopia. Friends, relatives, and neighbors provide traditional treatment free of charge or paid under more flexible arrangements, such as payment in cash or kind and on a credit basis. This is particularly prevalent in rural communities.
Plants are not grown for medicinal purposes, with the exception of the rare cases where certain food crops of medicinal value are grown. This is because the quantity of medicinal plants traded is very small and there is no coordination of large-scale added value and production. Therefore, in the future, there is a potential for higher demand for certain species and it is therefore important to recognize them and to conduct the necessary investigations into the techniques of propagation and cultivation. Such a program will also be the basis for small enterprises to improve the potential to generate local population income.