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The expansion and contraction of pinyon (Pinus spp.) and juniper (Juniperus spp.) woodlands in the western US is a broadly occurring phenomenon. The sagebrush (Artemisia spp.) vegetation type is vulnerable to woodland encroachment and much of the western US sagebrush domain has transitioned to PJ woodlands. These ecological state changes alter plant community structure and function and delivery of ecosystem services. This study applied a set of vegetation, soil, and rainfall simulation experiments over a range of scales (point to hillslope) to evaluate the ecohydrologic and erosion impacts of a shrubland-to-woodland ecological state transition on sagebrush rangelands on coarse-textured soils. The transition shifted the plant community from a fine to coarse structure and increased the connections between bare areas. Declines in shrub and herbaceous covers associated with pinyon and juniper woodland-encroachment increased the connectivity of runoff and sediment sources. Bare patches in the woodland contributed ample runoff and sediment at the fine spatial scale (0.5 m2) that facilitated flow paths and erosion over the hillslope scale. Overall, the shrubland-to-woodland transition marked substantive declines in cover and enhanced connectivity of runoff and sediment sources.