Observer effect
Photo courtesy Dr. Doug Karcher, University of Arkansas. The green patches in this non-treated plot within a wetting agent trial are the locations where the probes of a TDR soil moisture meter were inserted into the soil to measure soil moisture. The act of measuring (observing) soil moisture in itself impacted the turf performance where the measurements were taken. This "observer effect" is not common in turfgrass management, but when it happens, we may learn something.The possible practical implication of the observer effect here is that simply inserting solid tines into the surface of the plots reduced dryspot and improved movement of water into the soil. Venting turf surface susing small diameter solid tines every 14 days during the growing season may have broader imapact than simply improving gas exchange through the thatch/mat.
