Phenological description for the initial development stage of five Brazilian native forest species according to <scp>BBCH</scp> scale

Abstract A specific phenological scale designated for each forest species facilitates the standardization of different phenophases encountered during the growth and development of seeds to seedlings. This study is the first to apply the Biologische Bundesanstalt, Bundessortenamt and Chemical Industry scale to describe the phenophases during the initial development of five important Brazilian forest species: Bauhinia forficata Link, Ceiba speciosa (A.St.‐Hil.) Ravenna, Handroanthus chrysotrichus (Mart. ex DC.) Mattos, Handroanthus impetiginosus (Mart. ex DC.) Mattos and Tabebuia roseoalba (Ridl.) Sandwith. Phenological data were collected from experiments conducted across multiple sowing dates between 2022 and 2024 at the Federal University of Itajubá, in Itajubá, Minas Gerais State, Brazil. Two phenophases (main growth stages) were identified and described, that is, stage 0 (germination) and development stage 1 (leaf development), along with 12 sub‐stages. The species reached sub‐stage 110 (10th visible leaf on the main stem), marking the end of initial development, within approximately 171 days ( H. chrysotrichus ), 184 days ( C. speciosa ) and 190 days ( H. impetiginosus , B. forficata and T. roseoalba ), with variations observed in the duration of the sub‐stages (00‐110) in all species. This study highlights the variations in the duration of sub‐stages associated with the emergence and vegetative development phenophases across the five forest species studied. The binary codes assigned in this study can be used for multiple purposes, including the standardization and optimization of silvicultural techniques, as well as establishing comparative benchmarks for global warming studies, such as phenological cycle lengthening or shortening.