16 Better Crops/Vol. 99 (2015, No. 3) Abbreviations and notes: N = nitrogen; C = carbon. BRAZIL B razil is the world’s largest producer of both arabica (Cof- fea arabica L.) and robusta (Coffea canephora Pierre ex A. Froehner) coffee species. The two species are cultivated on an estimated 2.3 million ha in Brazil with an average of 2.1 to 3 million tons of coffee processed each year. Coffee grows in the extensive tropical region of Brazil characterized by two main seasons, the rainy season (from September to April) and a dry season (from May to September). In Brazil, the crop is largely grown under full-sun growing conditions, which is different from other large coffee-growing areas like Central America where the crop is commonly planted within a shaded agroforestry system. Water is commonly limited in perennial plants grown under full-sun, tropical conditions, and it is important to minimize water loss from surface runoff and evaporation. Evapotrans- piration varies from 3 to 5 mm per day (i.e., 3 to 5 L water/ m 2 /day). Soils are highly weathered with kaolinite and oxides present in the clay fraction. The dominant presence of these clay minerals limits soil water retention capacity to less than 0.5 mm per cm of soil (i.e., 0.5 L/m 2 /cm). Forages like Urochloa decumbens, Urochloa ruziziensis, and more recently, Urochloa brizantha are being intercropped on Brazilian plantations to accomplish the goals of protecting soil from the impact of torrential rainfall that is common in the tropics and reducing soil heating due to exposure to the sun. A coffee–forage intercropping system contributes to the goal of improving water availability, especially during the first six to eight years of establishment, when the plants are only exploiting a fraction of the total area. For example, the pres- ence of 3 t/ha of biomass increased soil moisture by 49% when compared with amounts measured without biomass addition (unpublished data). Forage biomass can increase water infiltration and reduce the speed of surface runoff, which both contribute to less soil loss by water erosion. Further, the temperature of soil surfaces (5 cm depth) often do not exceed 35°C. This is far less than 50°C temperatures that are commonly observed on exposed soil surfaces, leading to root system stress and even root death. In addition to protecting the soil, forage biomass can also increase fertilizer N recovery in its role as a cover crop. Nutri- ents absorbed from the soil volume through forage root growth in inter rows are recycled within the cropping system. Around 3 t/ha of forage biomass could provide the equivalent of 24 to 92 kg N/ha with a low release by decomposition of biomass under the coffee canopy (Pedrosa, 2013). Despite the numerous advantages of forage cultivation in a coffee-forage system, producers can often justify resisting its adoption due to misperception of yield-robbing nutrient, mainly N, competition. In crop systems in which there is input of fresh biomass, there is commonly an increase in availability of oxidizable C as a energy source for microorganisms and this decomposition immobilizes soil N (or releases N) depending on the C:N ratio of the added biomass. Addition of biomass with a C:N ratio above an equilibrium of 33:1 results in N immobilization due to the incorporation of the C source into the soil microbial biomass. Biomass C:N ratios below this equilibrium will increase soil N, since the supply exceeds microbial demand (Figure 1). Coffee plantations harvest forage biomass with a shredder, which distributes the biomass over the desired area. Biomass residue input commonly ranges between 3 and 5 t of dry mat- ter/ha/yr. During every forage harvest/spreading operation, biomass nutrients taken from a region where coffee plants By José Laércio Favarin, Tiago Tezotto, Adriene Woods Pedrosa, and Ana Paula Neto Coffee–Forage Intercropping is a Sustainable Production System for Brazil Cover crop forage grown under the coffee plant canopy serves as an important biomass source, which is proving effective at protecting this agro-ecosystem while improving the use of N. Ana Paula Neto Coffee-forage (Urochloa sp.) intercropping system.