Large areas of short grasslands have undergone vegetational changes in northern Mexico. Overgrazing, droughts, fire reduction, and climate are among the main factors responsible for these changes. This study was conducted in Cananea, Sonora, Mexico, to com pare vegetation changes in Bouteloua-Aristida grassland under regular conditions, with and without contour furrowing. Contour furrows, 3 m wide at the base and 1 m tall, were constructed at 30 cm elevation intervals using a disk furrower pulled by a D-6 bulldozer. The topography at the site is characterized by flat ranges with less than a 5% slope. Soils have a deep loamy sand texture. The climate is semi-warm and dry, with a mean annual precipitation of 425 mm and an average temperature of 15 °C. Changes were measured in three permanent plots of 400 m² each. Plant density, height, basal coverage, and forage production were monitored during the summer from 2013 to 2022 in ten permanent quadrants of 1 m² each per plot. A randomized block design was used, and the data were analyzed by ANOVA (P <0.05). Precipitation was near average for 4 years, below average for 3 years, and above average for 3 years. All variables were higher (P <0.05) in the contour furrowed areas than in the control plots. Plant density averaged 10.7 plants/m² in the control plots and increased by 116.8% ten summers after treatment in the contour furrowed areas. Plant cover increased by 67.5% in the same plots, and plant height increased by 47% ten summers after treatment in the contour furrowed plots. Total annual forage production averaged 635.8 kg D.M. ha»¹ in the control and 1,546.5 kg D.M. ha»¹ in the contour furrowed areas, resulting in an increase of 143.2%. We conclude that water harvesting through contour furrowing is an effective method to promote the establishment, development, and productivity of native grass species in short grass prairies.
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