The effects of forest degradation and use and establishment of tree-plantations on degraded or modifiedforest ecosystems at multi-decadal time-scales using tree-plantations on the streamflow response areless studied in the humid tropics when compared to deforestation and forest conversion to agriculture.In the Western Ghats of India (Uttar Kannada, Karnataka State), a previous soil hydraulic conductivitysurvey linked with rain IDF (intensity–duration–frequency) had suggested a greater occurrence of infiltration-excess overland within the degraded forest and reforested areas and thus potentially higherstreamflow (Bonell et al., 2010). We further tested these predictions in Uttar Kannada by establishingexperimental basins ranging from 7 to 23 ha across three ecosystems, (1) remnant tropical evergreen Forest (NF), (2) heavily-used former evergreen forest which now has been converted to tree savanna, knownas degraded forest (DF) and (3) exotic Acacia plantations (AC,Acacia auriculiformis) on degraded formerforest land. In total, 11 basins were instrumented (3 NF, 4 AC and 4 DF) in two geomorphological zones,i.e., Coastal and Up-Ghat (Malnaad) and at three sites (one Coastal, two Up-Ghat). The rainfall–streamflow observations collected (at daily and also at a 36 min time resolutions in the Coastal basins) over a2–3 year period (2003–2005) were analysed.In both the Coastal and Up-Ghat basins, the double mass curves showed during the rainy season a consistent trend in favour of more proportion of streamflow in the rank order DF > AC > NF. These doublemass curves provide strong evidence that overland flow is progressively becomes a more dominantstormflow pathway. Across all sites, NF converted 28.4 ± 6.41stdev% of rainfall into total streamflow incomparison to 32.7 ± 6.97stdev%in AC and 45.3 ± 9.61stdev%in DF.Further support for the above trends emerges from the quickflow ratioQF/Qfor the Coastal basins.There are much higher values for both the DF and AC land covers, and their rank order DF > AC > NF.The quickflow response ratioQF/Pis also the highest for the DF basin, and along with the QF/Qratio,can exceed 90%. The corresponding delayed flow response ratios,QD/Pclearly show the largestQDyieldsas a proportion of event precipitation from the Forest (NF1). The application of linear model supportedthese differences (e.g. 10–36% difference between NF and DF,p< 0.001) in the storm hydrologic responseof the Coastal basins. The exception wasQF/Pwhere there was a higher uncertainty connected with interbasin mean differences. Cross-correlation plots for rain–streamflow and corresponding lag regressionmodels for three storm events in the Coastal basins suggested the existence of alternative stormflowpathways with multiple lags with peaks between12 and 24 h in NF, compared to respective bimodalpeaks at1 and 16 h in AC and1 and 12 h in DF. The long time lags for NF are suggestive of deep subsurface stormflow and groundwater as the contributing sources to the storm hydrograph. The short timelags in DF and AC are indicative of overland flow and so ‘memory’ of the previous degraded land cover isretained in AC as supported by previous hydraulic conductivity data. As potential and actual evapotranspiration is likely to be depressed during the monsoon, differences in streamflow and run-off responsesbetween land-cover types is largely attributed to differences in soil infiltration and hydrologic pathways.Enhancing infiltration and reducing run-off in managed ecosystems should be explored in the terms ofthe context of other ecosystem services and biodiversity.