The debate over the origin of the flowering cherry in Rosaceae has been resolved by recent molecular studies (Ohta et al., 2007; Cho et al., 2014, 2016, 2017; Cheong et al., 2017; Baek et al., 2018; Cho and Kim, 2019), which show that the widely cultivated flowering cherry has a genetically distinct origin from the wild flowering cherry in Korea. Prunus × nudiflora (Koehne) Koidz., commonly known as “King cherry,” is a natural hybrid between P. itosakura var. ascendens (Makino) Makino and P. jamasakura Siebold ex Koidz./P. sargentii Rehder, and is native to Jejudo Island in Korea (Cho et al., 2014, 2016, 2017; Baek et al., 2018; Cho and Kim, 2019). The holotype specimen of P. × nudiflora was collected on Mt. Hallasan in 1908 by Taquet, who made many collections on Jejudo Island during his assignment to the Seoheung-ri Catholic Church from 1902 to 1915. Prunus × yedoensis Matsum., commonly known as “Somei-Yoshino cherry,” is an artificial hybrid between P. itosakura var. ascendens and P. speciosa (Koidz.) Nakai, and is presumed to have been produced in Japan (Takenaka, 1963; Iketani et al., 2007; Cho and Kim, 2019).

Jung (2019), in “The Gift of Emile Taquet,” notes that the cherry trees planted at the Catholic Archdiocese of Daegu are the same age as when Taquet, the discoverer of P. × nudiflora, was active in Daegu. He suggests that these trees may have been transplanted by Taquet and should therefore be identified as P. × nudiflora. Later, a DNA fingerprinting analysis reported in The Catholic Times of Korea (https://www.catholictimes.org/article/201603290153897) found that the cherry trees at the Catholic Archdiocese of Daegu are genetically identical to a King cherry tree of P. × nudiflora in Bonggae-dong, Jejudo Island. This tree is part of a wild King cherry population designated as a National Natural Monument in Korea.

Cho et al. (2016) identified the chloroplast haplotype of cherry trees at the Catholic Archdiocese of Daegu and analyzed the phylogenetic relationships among P. × nudiflora, P. × yedoensis, and P. itosakura var. ascendens using the rpl16 gene and the trnS-trnG intergenic spacer. The study showed that the cherry trees at the Catholic Archdiocese of Daegu were genetically distinct from P. × nudiflora and not closely related to P. itosakura var. ascendens, a Korean species involved in the origin of P. × nudiflora.

In the protologue describing P. × nudiflora as a variety of P. × yedoensis (P. × yedoensis var. nudiflora), based on Taquet’s specimen, Koehne (1912b) observed differences between the two taxa in leaf blade length, pedicel length, sepal margin, and hair distribution on the style. He noted that P. × nudiflora has soft, spreading hairs on the style extending up to one-fourth of its length, whereas P. × yedoensis has hairs halfway up the style (Koehne, 1912b). Leaf, pedicel, and sepal characteristics are highly variable in P. × nudiflora and cannot be used as diagnostic characters (Kim et al., 1998; Han et al., 2022). Recently, the surface of winter bud scales has been proposed to distinguish P. × nudiflora from P. × yedoensis (Han et al., 2022): the bud scales of P. × nudiflora are glabrous, whereas those of P. × yedoensis are densely pubescent.

Although both Jung (2019) and Cho et al. (2016) conducted molecular analyses of the same trees, their conclusions were mutually contradictory, and no detailed morphological investigation has yet been conducted. Accordingly, this study aims to clarify the floral characteristics of cherry trees planted at the Catholic Archdiocese of Daegu.

Typical plants of four cherry species and cherry trees planted at the Catholic Archdiocese of Daegu were included in this survey. On March 29, 2025, nine cherry trees within the Catholic Archdiocese of Daegu were examined for flowers, and on December 22, 2025, for winter buds. Among these, one tree was officially designated the Taquet’s cherry tree. There are six additional trees planted around it, and two other trees of comparable age in the vicinity. We examined more than 10 inflorescences per individual.

In addition, we examined six accessions of P. × nudiflora from Bonggae-dong on Jejudo Island on April 9, 2013, and from Shinlye-ri on April 13, 2019. These locations, which host very old trees, are designated as the natural habitat of P. × nudiflora, and we included typical trees to represent the wild population of the species. For comparison, we examined cultivated materials of P. × yedoensis from three locations: Gurye-gun (Jeollanam-do) on April 5, 2013; Seoul (at the National Meterological Museum) on March 30, 2014; and Gimcheon-si (Jikjisa Temple, Gyeongsangbuk-do) on April 12, 2013.

Furthermore, plants of P. itosakura var. ascendens from Gurye-gun (Hwaeomsa Temple) on April 5, 2013, and of P. leveilleana Koehne from Pocheon-si (Gyeonggi-do) on May 4, 2013, were studied. For each location, more than three accessions were examined during the flowering season from 2013 to 2019. The first author spent one day investigating floral characters at each location.

Our observations of floral traits in the Prunus collections (Fig. 1A), purportedly transplanted by Taquet at the Daegu Diocesan Office (Jung, 2019), showed that the cherry trees have glabrous styles (Fig. 1C), distinguishing them from both P. × nudiflora and P. × yedoensis, which have pubescent styles (Fig. 1F–I). All nine trees in the vicinity exhibited the same feature. In addition, the trees at the Daegu Diocesan Office have relatively slender pedicels with low hair density (Fig. 1B), further distinguishing them from P. × nudiflora and P. × yedoensis.

Typical plants of P. × nudiflora from Shinrye-ri (Fig. 1D) and those in Bonggae-dong, Jejudo (Fig. 1E, F) display the hair pattern described by Koehne (1912b), in which hairs cover up to a quarter of the style. The pubescence patterns on the style in P. × yedoensis tend to differ from those in P. × nudiflora, with hairs distributed in the lower half of the style (Fig. 1G–I). There are slight variations in pubescence distribution. Plants grown along the roadside in Gurye-gun show that hairs are present only up to just below the midpoint of the style (Fig. 1G), whereas the cherry tree at the National Meteorological Museum in Jongno-gu, Seoul (Fig. 1H), and the trees at Jikjisa Temple in Gimcheon, Gyeongbuk (Fig. 1I), exhibit hairs distributed up to the midpoint of the style. Although the distribution of hairs on the style alone does not satisfactorily distinguish P. × nudiflora from P. × yedoensis because of the wide range of morphological variation in the natural hybrid (Kim et al., 1998; Baek et al., 2018; Han et al., 2022), our observations for the sampled individuals are consistent with Koehne’s notes (Koehne, 1912b). Therefore, the Taquet’s cherry tree is not closely related to either P. × nudiflora or P. × yedoensis.

Morphological characteristics of winter buds further support the conclusion that the Taquet’s cherry tree cannot be identified as P. × nudiflora. Winter buds of P. × nudiflora are glabrous (Fig. 1M), whereas those of P. × yedoensis are densely covered with hairs (Fig. 1N) (Han et al., 2022). The Taquet’s cherry tree has densely pubescent winter buds (Fig. 1O). Thus, our morphological findings on the flowers and buds of the Taquet’s cherry tree align with the chloroplast haplotype data reported by Cho et al. (2016).

Prunus itosakura var. ascendens, the maternal parent of both P. × nudiflora and P. × yedoensis (Iketani et al., 2007; Cho et al., 2014, 2016; Baek et al., 2018; Cho and Kim, 2019), bears hairs extending to the middle of the style, as seen in the specimen from Hwaeomsa Temple in Gurye-gun (Fig. 1J), a designated national monument. In contrast, P. leveilleana has a glabrous style (Fig. 1K), as in the Taquet’s cherry tree. It is interesting to note that the type specimens of P. leveilleana housed in the Royal Botanic Garden Edinburgh Herbarium were collected by Taquet in 1909 from the mountains of Mokpo (Koehne, 1912a). However, P. leveilleana bears an umbellike inflorescence (Fig. 1L), unlike the Taquet’s cherry tree, which has a corymbose inflorescence (Fig. 1B). The winter bud scales of P. leveilleana are sparsely pubescent (Fig. 1P), making it difficult to identify the Taquet’s cherry tree as P. leveilleana. However, further investigation is needed to understand the range of variation in inflorescence shape and bud scale pubescence in wild populations of P. leveilleana. Furthermore, high-resolution molecular markers at the population level, such as genome-wide SNP data, and detailed morphological analysis of floral characters, including winter bud scales, inflorescence type and shape, pedicel diameter and pubescence, hypanthium shape and pubescence, and style pubescence, across the native species of Prunus are warranted.