Traditional healers in Thailand are a primary source of health care for the Thai people. Highly experienced traditional healers are generally older people and they continue to pass away without recording or passing on their knowledge. Consequently, the cumulative knowledge held by traditional healers regarding the use of medicinal plants is being eroded and could be lost. In this study, we aimed to identify and document the medicinal plants and associated ethnobotanical knowledge held by traditional healers in Roi Et in northeastern Thailand. Data and plant specimens were collected from four traditional healers of the Phu Tai people. They were selected by purposive sampling and questioned using a semi-structured interview. The interviews covered their training, the ailments treated, treatment techniques, method of preparation and in addition, several healing sessions were observed. During field walks, we searched for the medicinal plants with the healers to review and document the availability of medicinal plants at each locality and in different habitats around the villages. Use values (UV) were calculated to estimate the importance of each medicinal plant and informant agreement ratios (IAR) were calculated to understand how widely known the uses were. The four Phu Tai traditional healers knew 162 medicinal plant species in 141 genera and 63 families. The family with the most medicinal plants was Leguminosae with 15 species. The plant part that they used most commonly was the stem, which was used for 82 species (49%). The most common preparation method was decoction, which was done for 124 species (75%). The most important and widely used medicinal plants were Rothmannia wittii, which had the highest use value (UV = 1.7). Most medicinal plants were used for treating tonic (34 species (21%)). Jaundice had the highest informant agreement ratio (IAR = 0.5). The most common life form among the medicinal plants was trees (56 species (34%)). The medicinal plants were mostly collected in community forests (81 species (49%)). Considering the richness of the healer’s pharmacopeia, and the fact that their profession is not being perpetuated, this study points to the urgent need to document the traditional knowledge from the old herbalists before it disappears with the last practitioners from rural communities in Thailand.

This study explores the ethnobotanical significance of plant species used in the Heet Sip Song (Twelve Monthly Merit-Making) ceremonies in Roi Et Province, Northeastern Thailand. A total of 80 plant species across 73 genera and 42 families were documented. The findings reveal that plants play multifaceted roles in ceremonial life, serving both symbolic and practical purposes rooted in spiritual belief systems and seasonal agricultural cycles. Quantitative analyses using Cultural Significance Index (CSI), Species Use Value (SUV), Genera Use Value (GUV), and Relative Frequency of Citation (RFC) highlighted the prominence of key species such as Oryza sativa, Musa acuminata, and Saccharum officinarum in ritual contexts. While staple crops dominate in frequency and cultural value, less commonly cited wild species fulfill specialized functions, reflecting deep local ecological knowledge. The integration of ritual and plant use promotes biodiversity conservation by maintaining plant populations and reinforcing sustainable harvesting practices. These results emphasize the vital role of traditional knowledge in conserving both biological and cultural diversity. As environmental pressures increase, this study underscores the importance of supporting community-led conservation efforts that honor indigenous practices and their contributions to ecological resilience.

Edible underground storage organ (EUO) plants, including tubers, rhizomes, corms, and root tubers, play a crucial role in food security, nutrition, traditional medicine, and local livelihoods, yet many regions of northeastern Thailand, including Maha Sarakham Province, remain underexplored in ethnobotanical research. This study aimed to document the diversity, traditional uses, and economic importance of EUO plants in the province. Field surveys, local market assessments, and ethnobotanical interviews were conducted, and voucher specimens were collected. Quantitative indices, including the Cultural Food Significance Index (CFSI), Fidelity Level (%FL), and economic value (EV), were applied to evaluate the cultural, medicinal, and economic significance of each species. A total of 53 EUO taxa from 22 families were recorded, representing both wild-harvested and cultivated resources. Dioscoreaceae and Zingiberaceae were among the most species-rich families. Among the EUO plants, Allium ascalonicum L. stood out for its cultural significance, Gloriosa superba L. for its medicinal importance, and Smallanthus sonchifolius (Poepp.) H.Rob. for its economic value. Several other EUO plants exhibited high cultural consensus and consistent use patterns, underscoring their integration into local diets, traditional healthcare, and rural economies. The study demonstrates that EUO plants contribute not only to dietary diversity and cultural identity but also to rural economies. These findings highlight the importance of conserving biological and traditional knowledge and promote sustainable cultivation and horticultural development of priority EUO species to strengthen local food system resilience.

Zingiberaceae is a diverse and culturally significant plant family across tropical Asia, yet in Roi Et Province, Thailand, it has remained poorly documented. This study aimed to provide the first comprehensive assessment of Zingiberaceae in Roi Et Province, Thailand. Previous studies in the region have been limited and did not systematically document species occurrence. The assessment began with an overview of species diversity, followed by an investigation of their ethnobotanical uses, an evaluation of their horticultural potential, and an assessment of their conservation status. Field surveys were conducted throughout Roi Et Province across various habitat types using exploratory sampling to record all observable Zingiberaceae species. Species were identified based on morphological characteristics and comparisons with existing taxonomic literature. A total of 97 species were recorded, including 86 native and 11 introduced taxa, with 23 species endemic to Thailand and 25 species featuring new distributions reported for the province. Species richness was highest in cultivated habitats, likely reflecting the active role of traditional agroecosystems in conserving both native and introduced taxa. Natural habitats such as wetlands and dry evergreen forests hosted species with restricted distributions, underscoring the need to preserve ecological heterogeneity. Ethnobotanical interviews revealed widespread local use of rhizomes and inflorescences for food, medicine, ornamentation, and ceremonial purposes. Phenological observations indicated synchronized flowering and fruiting aligned with the monsoon season, which are traits that supports successful reproduction but may also increase vulnerability under shifting climate regimes—highlighting the importance of monitoring for conservation and guiding optimal harvest timing. These findings demonstrate that both natural and cultivated systems are integral to maintaining Zingiberaceae diversity in the region. Conservation strategies should prioritize habitat protection, support traditional cultivation practices, and promote further research into economically and culturally valuable species.

This study investigates the plant diversity, ethnobotanical knowledge, and traditional uses of plants by the Lao Isan ethnic group in Na Chueak District, Maha Sarakham Province, Thailand. A total of 109 plant species, representing 48 families, were identified, with the Fabaceae, Euphorbiaceae, and Rubiaceae families being the most prevalent. This study highlights the ecological and cultural significance of these plants, many of which serve multiple purposes, including food, medicine, and other purposes. A use value analysis revealed that plants such as Schleichera oleosa (Lour.) Oken, Trigonostemon reidioides (Kurz) Craib, and Vietnamosasa pusilla (A.Chev. & A.Camus) T.Q.Nguyen have high functional importance in local cultural and medical practices. The Relative Frequency of Citation indicated that these species are integral to the community’s plant knowledge, with Trigonostemon reidioides and Vietnamosasa pusilla being especially prominent. Additionally, 62 species were identified for medicinal use, emphasizing the community’s reliance on plant-based remedies. This study also discusses the Informant Consensus Factor and Fidelity Level, which reveal strong agreement on the effectiveness of certain plants, particularly for treating digestive, respiratory, and wound healing conditions. This research contributes to the documentation of ethnobotanical knowledge, emphasizing the importance of traditional plant use for cultural continuity and sustainable resource management.

Medicinal plants remain vital in the Phu Tai community in Amnat Charoen in Thailand. Traditional healers’ knowledge is largely undocumented in the literature. Our objective was to document their medicinal plant practices to preserve this valuable knowledge. Our informants were 15 Phu Tai healers. We calculated use values (UV), family importance values (FIV), and informant agreement ratios (IAR) to gauge the significance of the 211 medicinal plants used by the healers. The most important plant families were Fabaceae and Zingiberaceae (FIV = 93). Kha min (Curcuma longa) was the most important medicinal species (UV = 0.66). The decoction was the most common preparation method (85%). Skin/subcutaneous cellular tissue disorders had the highest informant agreement ratio (IAR = 0.73). Shrubs were the most common life form (36%) among the medicinal plants; the majority were collected from community forests (51%) and were native to Thailand (86%). The most frequently used plant part for medicine was the leaf (27%). Medicinal plants that can be purchased were Ueang mai na (Hellenia speciosa), Thep tharo (Cinnamomum parthenoxylon), and Som khon (Talinum paniculatum). Interestingly, monks served as traditional healers. The healer’s age and education were not correlated with the number of medicinal plants they knew. The Amnat Charoen healers possess a rich traditional knowledge of medicinal plants. The information reported here is invaluable for further research in the field of cross-cultural ethnobotany and ethnopharmacology.