Estimating yield and control costs of Pinus spp. invasions – a case study in a municipal protected area in Atlantic Forest, Florianópolis, Brazil

Abstract

Pines invading a municipal protected area in southern Brazil were eliminated over 17 days at a cost of USD 10,000. The number of pines eliminated per day varied with (1) slope; (2)vegetation; and (3) pine density. Yield was assessed based on the combination of these threefactors. Seven yield classes were defined to estimate the number of pines a team of four workerscan eliminate per day. Yield varied between approximately 100 and more than 700 pines perday. A formula was developed to provide yield estimates to support management of control ac-tivities. The formula can be adjusted to other limiting factors. A breakdown of costs is presentedfor reference. Cost varied from USD 5.45 to USD 0.88 per tree. Despite the higher individual cost,isolated trees must be controlled first to avoid higher future costs from abundant seed spread.