The present invention relates to novel solid forms of 3-difluoromethyl-1-methyl-1H-pyrazole-4-carboxylic acid (9-isopropyl-1,2,3,4-tetrahydro-1,4-methano-naphthalen-5-yl)-amide, such as crystal modifications and hydrates, compositions comprising these novel solid forms and to the use thereof in the control of disease infestation in cultivated plants.