One to two-year-old seedlings of tree species found in riparian forests were investigated for frost sensibility as of June/August 1990, in Moji-Guaçu Municipality. São Paulo State. At least two frost affected the seedlings in the experimental area during this period. Around 2750 seedlings from 13 species were planted in a 2.5-hectare area on the shores of the Moji-Guaçu river. Variations in total height and budding were recorded monthly. Scores from to 5 were given based on pre-stablished criteria. General morphology, initiation of vegetative growth and seedling behavior were observed in relation to riverbank proximity. The most obvious effects on seedlings were changes in leaf color and texture; the leaves turned blackish or reddish, followed by abscission and total or partial death of aerial parts. Of the species investigated, planting restrictions on seedlings in frost-prone areas should be applied only to Platycyamus regnelli Benth. (Leguminosae), Hymenaea courbaril L. (Leguminosae) and Alchornea s (Euphorbiaceae). The other species showed considerable capacity for recuperation, suggesting resistance and/or tolerance to frost damage.
riparian forest; frost; native species