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Poplar is popular among farmers and planted widely in the form of block and boundary systems. The preferences of farmers are shifting much more towards bund plantations due to their smaller yield reductions and can take up kharif and rabi crops till rotation. As for boundary plantations, farmers tend to grow trees in any direction without concern for yield reduction or profitability. Against this background, an experiment was designed by planting poplar at 2 m intervals in East–West (E–W) and North–South (N–S) directions during 2008 to determine the production potential and economic viability of boundary plantations and their effect on sorghum (Sorghum bicolor) and wheat (Triticum aestivum) crop rotations till harvesting of the trees. The experiment comprised three variables: stand age (years); four aspects (northern and southern E–W rows, eastern and western N–S rows; these four aspects are considered by dividing the tree lines); and six distances from tree the lines (0–3, 3–6, 6–9, 9–12, 12–15, 15–18 m and a control). A split-split plot design with three replicates was used. A significant reduction of fodder biomass of sorghum and wheat yield was observed up to 9 m distant from the tree line: the reduction was 10 to 60% for the kharif season and 7.2 to 29.5% for rabi crops from the second year to eight years after planting, respectively. Interestingly, the poplar boundary plantation had a favorable microclimatic effect from 9 to 15 m distance from the tree line, which increased crop yields compared with the control. The total dry wood production of poplar in the E–W direction (166.99 mg ha−1) was almost two times more than production for the N–S direction (82.62 mg ha−1) at 8 years of rotation. The economic analysis of this study concluded that an E–W boundary plantation of poplars exhibited the maximum net returns of INR 549,367 ha−1, a net present value of INR 222,951 ha−1, a BC ratio of 1:1.65, an IRR of 85% and an LEV of INR 1,220,337 ha−1. Therefore, it is concluded that the intercropping of a sorghum-wheat crop rotation in E–W boundary plantations was more beneficial for enhancing farm income over traditional agriculture in north India.