Twenty-Five Years of Subsurface Drip Irrigation Research – Progress and Potentialities.

In 1989, K-State Research and Extension initiated efforts to develop the techniques for successful application of subsurface drip irrigation (SDI) for crop production in the U. S. Great Plains region.  With regards to soil physics, design considerations, such as dripline depth, dripline spacing, emitter spacing and emitter discharge all have some bearing on the success of this technology on the deep silt loam soils of this region.   Similarly, corn germination and establishment, rooting and ultimately corn yields are strongly related to the soil water redistribution.  Conjunctive management of both irrigation and inseason N fertigation are important for corn production with SDI.  Anecdotal observations have shown that nitrogen can sometimes be positionally unavailable when surface applied to SDI corn under drought conditions.  This paper will summarize some of the many years of results and future opportunities at K-State and also discuss some of the remaining global challenges to SDI that are of most interest to the soil physics community.