Nursery and field establishment techniques to improve seedling growth of three Costa Rican hardwoods

Seedlings of three economically important and ecologically different native hardwoods, Cordia alliodora (Boraginaceae), Hyeronima alchorneoides (Eupho rbiaceae), and Calophyllum brasiliense (Clusiaceae), were grown in Rootrain ers (R) (a book-type container), paper pots, and plastic bags filled with e ither soil, soil with fertilizer, or compost substrates. After transplantin g in the field, treatments with and without fertilizer and herbicide were a pplied to all nursery stock types. In the nursery, species responded primar ily to substrate type. Cordia grew better in bags of soil with NPK fertiliz er and compost than in unamended soil, probably responding to higher nitrog en availability. Despite large treatment differences at planting, there wer e no significant differences in plant size after one year in the field betw een book containers and bags. The exception were stump plants that were sho rter and had higher mortality. Hyeronima grew better in compost than in soi l with or without fertilizer, probably responding to higher phosphorus avai lability and lower bulk density of the compost. Plants produced in compost were also bigger after one year's field growth. Plants produced with soil o r in paper pots had higher mortality. Calophyllum grew less in compost comp ared to soil and grew better when micronutrients were added to the compost and soil. In the field, seedling produced in soil or with micronutrients ha d higher survival or growth, respectively. In general, species grew better with herbicide and fertilizer application after transplanting. However, the re were no interactions with nursery treatments. Responses to field treatme nts were independent and thus additive to the nursery treatments. Differenc es in species response can be related to biomass allocation patterns and ec ology of the species.