Macadamia intercropping into an inefficient adult coffee plantation is economically advantageous

Abstract

The paper's hypothesis was that intercropping macadamia (Macadamia integrifolia Maiden & Betche) in an Arabica coffee (Coffea arabica L.) plantation would increase land-use efficiency and economic results. An experiment was conducted in southeastern Brazil to evaluate the planting of macadamia intercropped into a declining adult coffee plantation where trees were pruned, removed, or neither on the payback period compared with a macadamia monoculture. The experiment was arranged in a randomized complete block design with six treatments and four replications. Treatments consisted of four systems of planting macadamia intercropped within a coffee plantation (T1-unpruned coffee trees; T2-side pruning of two coffee trees; T3-stumping of two coffee trees; T4-removal of one coffee tree), and a coffee monocropping and a macadamia monoculture planted where coffee crops were eradicated (macadamia monocropping) as control. We evaluated macadamia plant growth and economic results across four growing seasons and considered three macadamia plant arrangements. At 46 mo after planting, macadamia plants intercropped with unpruned coffee trees had lower plant height (28%) and trunk diameter (63%) than those planted in macadamia monoculture. Treatments T3 and T4 provided greater growth of macadamia plants. Coffee yield losses caused by pruning or removal of coffee trees were not significant, regardless of the macadamia plant arrangement used. The implantation of the macadamia intercropped with an inefficient adult coffee crop proved to be economically more advantageous than the implantation of a macadamia orchard in monoculture.