Alley cropping in Croatia

Alley cropping in Croatia by Zeljko Serdar

Alley cropping, also sometimes referred to as "intercropping", is the practice of planting rows of trees with a companion crop in between. Frequently this can be used to add another cash crop but it also reduces surface water runoff and erosion, improves soil health and fertility, and reduces wind erosion. Depending on the crops chosen, it can also modify the microclimate for improved crop production or improve wildlife habitat. Multiple crops, when managed appropriately, can keep a farm more productive throughout the year, increasing income and reducing risks associated with monocropping. 

Alley cropping can be viewed as recreating the structure of a savanna in an agroforestry system with multiple canopy layers consisting of a design that contains an overstory of nut trees, a mid-layer of fruiting small trees and shrubs, and a groundcover of annual crops or perennial grass groundcover. In nut-based agroforestry systems, crops grown in the alleys between tree rows provide annual income while the longer-term nut crop matures. Primary agroforestry and alley cropping design criteria include imitation of the structure and function of natural ecosystems with species that generate an economic yield to support the farmer.

Alley cropping in Croatia by Zeljko Serdar

Growers planning to farm between tree rows need to think about the width of their alleyways. Between-row spacing is primarily determined by machinery width, and mature size of nut tree species, with secondary considerations for sunlight requirements of the alley crop. With closer spacing, the intercrop grown in the alley will encounter light competition at an earlier age, requiring a more rapid change to shade-tolerant intercrops. Wider spacing makes intercropping easier but delays the fullest realization of economically viable nut crop yields.

Alley cropping in Croatia by Zeljko Serdar

Recommended principles for designing the cropping system based on this approach include selecting species for complementary functional traits, developing complex trophic levels, and reproducing ecological succession. Trait-based agroecology has emerged as one of the dominant paradigms in terrestrial ecology. Studies that evaluate the complex linkages between functional traits, functional diversity, and ecosystem functioning have recently begun to explore concepts surrounding “multifunctionality,” the idea that multiple ecosystem functions should be considered as a management goal. Multifunctionality has clear implications for trait-based agroecology and for agroforestry, where land managers manipulate on-farm diversity to enhance ecosystem services beyond yield alone.