A time-series of MODIS Terra daily 500 m resolution surface reflectance data is investigated to examine the effect of current land management activity taking place on an upland peat site in North Wales. A catchment-scale controlled experiment has been set up to monitor the effect blocking of the artificial drainage channels (`grips') has on the ecosystem dynamics. The reflectance data and the Normalised Difference Vegetation Index (NDVI) and Normalised Difference Water Index (NDWI) were compared both before and after the period of grip blocking and between the control and treated catchmensts. No change was observed as a result of the grip blocking. Reasons why this might be the case are discussed.