EMERGENCE OF SEEDLINGS OF NATIVE TIMBER TREES OF YUCATAN PENINSULA

Abstract

The regional biodiversity of Yucatan Peninsula includes native tree species with potential to be used en reforestation; however, to use this potential, it is necessary to know the ecological preferences of the species. Therefore, the emergence of seedlings of native timber trees were assessed under different levels of shade (0, 35, 60 and 90%) at the nursery, and seedling emergence and survival after direct sowing of seeds in the lower and higher parts of the hills that are common in the Pensinsula, as well as the following species: cedar (Cedrela odorata), chakté (Caesalpinia mollis), ciricote (Cordia dodecandra), ja’abín (Piscidia piscipula), tzalam (Lysiloma latisiliquum) and granadillo (Platymiscium yucatanum). At the nursery, high levels of shade (60% and 90%) reduced the number of days required to attain 95% of the number of emerged seedlings in C.odorata. C. mollis was the only species that showed significant differences (p = 0.006) in the emergence of seedlings among shade treatments, obtaining the highest emergence per cent (53 and 49%) at 0% and 35% of shade. In the field, P. piscipula (p = 0.005) showed higher emergence in the lower part of the hills, and C. mollis (p = 0.015) in the higher part (1.9%). C. odorata showed higher survival (73.5%) in the high position (p = 0.001) and C. dodecandra (84.2%) in the low position (p = 0.02). The aforementioned results show that species differ in preferences for positions in the landscape, and that shade per cent has little effect on seedling emergence.