Rubus spp. seeds have a thick protective endocarp and testa (seedcoat) that can
restrict germination even under favorable conditions. The effect of pregermination
treatments were studied in Rubus chamaemorus L., R. eustephanos Focke ex Diels, R.
idaeus 'Amber' L., R. leucodermis Douglas ex Torrey & A. Gray, R. multibracteatus A....