The study area lies in Dhaka, Gazipur, Manikganj and Tangail districts that are located in central Bangladesh, in between 23º38'−24º48'N and 89º41'−90º42'E (BBS, 2011). In this study, data were collected from the representative homesteads of these districts from 2013 to 2018, mostly in rainy and winter seasons. A total of 280 homesteads per district, total 1120 homesteads belonging to 40 villages of 20 upazilas of four districts, composing an area of about 4.64 sq km., were visited through 240 field trips. Four categories of homesteads, old joint, old isolated, new joint and new isolated, were selected from each district for better representation of the homesteads following a preliminary reconnaissance survey. The old homesteads selected for this study were 20 years to 80 years old and the new ones were five years to less than 20 years old. The selected homesteads of each of the four districts were equal in number, more or less homogenous and located in plain land areas in order to promote reasonable comparison. Representative specimens of each species with flowers and fruits (monocots) or sporangia (pteridophytes) were collected during the field trips. The collection, preparation, pressing, drying, mounting, and storing of representative plant specimens were completed following routine herbarium methods (Jain and Rao, 1977; Hyland, 1972). The collected specimens were identified through consulting the experts, taxonomic descriptions and keys available in the relevant literatures (Hooker, 1872-1897; Wu et al., 1995-2013), and matching with relevant voucher specimens preserved at Jahangirnagar University Herbarium (JUH), and Bangladesh National Herbarium (DACB). The nomenclatural databases (TROPICOS, 2010; The Plant List, 2013; International Plant Names Index, 2015) and relevant literarures (Khan and Rahman, 1989-2002; Rahman, 2003; Rahman and Khanam, 2003; Khanam and Ara, 2007-2008; Ara and Khan, 2009; Huq, 1986a; Siddiqui et al., 2007; Ahmed et al., 2008, Ahmed et al., 2008-2009; Jacson, 1893-1955; Wu et al., 1995-2013 and Watson et al., 2011) were consulted for knowing the valid and updated nomenclature of each taxon. The families of pteridophytes have been placed first and arranged following the classification system of Pichi (1977) and those of the monocotyledons according to Cronquist’s system (Cronquist, 1981). The families Amaryllidaceae and Colchicaceae, not included in Cronquist (1981)’s System, are placed besides their close family Liliaceae. The genera and species under each family have been arranged alphabetically. All voucher specimens are housed at JUH. The similarities in species composition in the homesteads of four districts have been measured following Jaccard coefficient (Jaccard, 1912).