INTERSPECIFIC VARIATION IN RATES OF TRUNK WOUND CLOSURE IN A PANAMANIAN LOWLAND FOREST

We evaluated the ability to dose wounds inflicted with a drill to the trunks of seven common tree species from Barro Colorado Nature Monumen t, Panama. We predicted that species lacking wood antimicrobial activi ty would rapidly dose wounds to prevent pathogen entrance, while those species with wood antimicrobial defenses need nor necessarily exhibit fast wound closure. The species studied were Alseis blackiana, Gustav ia superba, Miconia argentea, Poulsenia armata, Protium panamense, P. tenuifolium, and Tetragastris panamensis. Callus, resins, and latex we re all involved in wound closure, but mechanisms varied among species: after 3 months, the only pioneer species, Miconia, had minimal diamet er closure; Alseis showed intermediate closure only by callus; and the other five species (which did not differ) had almost completely plugg ed their wounds by means of combined callus and resin production (Tetr agastris and both species of Protium), latex (Poulsenia), or callus an d woody Bakes (Gustavia). Our initial prediction was supported for Gus tavia and Poulsenia (i.e., rapid wound closure and no wood antimicrobi al activity) but not for Tetragastris and Protium (that showed both ra pid wound closure and strong wood antimicrobial activity); Miconia sho wed slow wound closure and no wood antimicrobial activity. Only for Al seis, was wound closure rate proportional to stem diameter growth.