During the survey conducted by KFRI, a list of plants of the National Park is prepared. Since this was a rapid survey, the list is not exhaustive and contains mostly perennial species. 62 species of trees, 174 species of herbs and shrubs and 39 species of climbers were recorded during the survey. For a complete list of plants occurring in the Park, a detailed inventory study covering different seasons is necessary. The list of trees, herbs, shrubs and climbers reported from the Park are given in Annexure 2.

As per the study conducted in the Sholas of Idukki District by K. Swarupanandan et al of KFRI, 543 species of pteridophytes and angiosperms were recorded in Mannavanshola and Eravikulam. Nearly 20% (109 species) of the taxa are ‘endemic’ and 25% (128 species are classified as ‘rare’ and another 26 species are considered to be in a ‘threatened state’. Two rare pteridophytes namely, Elaphoglossum stelligerum Sledge and Pleopeltis macrocarpa (Bory ex Willd.) Kaulf collected from Mannavanshola are new records to Kerala (Kumar, 1997). The list of endemic, rare and threatened species of pteridophytes and angiosperms are given in Annexures 6 and 7.

The fungi species of Mannavanshola were also studied by the Plant Pathology division of KFRI. About 11 species of fungi are recorded from this Shola of which Collectotrichum acutatum is a new record to Kerala. The soil microflora of the shola forests of Eravikulam and Munnar were also studied by various research organisations.