Frost Heaving in Alfalfa Establishment on Soils with different Drainage Characteristics

The susceptibility of alfalfa (Medicago sativa L.) to frost heaving is a major problem in stand establishment in southern Illinois. This study was conducted at Carbondale, Illinois, to determine the effects of frost heaving on the establishment and production of alfalfa cultivars in relation to soil drainage characteristics. Four alfalfa cultivars (‘Cody’, ‘Spredor’, ‘Weevlchek’, and ‘WL-307’) were seeded on three soil series, a deep well-drained AIford (Typic Hapluadalf, fine-silty mixed mesic), a moderately well-drained Hosmer (Typic Fragiudalf, fine-silty, mixed, mesic) with a fragipan starting at a depth of 60 to 70 cm, and a nearly level poorly-drained Weir (Typic Ochraqualf, fine, montmorillonitic, mesic). Piezometers were installed in each soil to monitor the presence of perched water tables and their position to the soil surface. Small wooden dowels were used to assess soil movement in relation to alfalfa seedling heave. The higher amount of heaving as measured by the distance wooden dowels were raised above a reference point occurred when the night temperature was a few degrees below freezing and the day temperature was above freezing, with a perched water table near the soil surface. Poorly-drained, Weir soil had the highest perched water table, most alfalfa seedling heave, greatest alfalfa seedling winterkill, and most dowel heave. In contrast, well-drained Alford series had no perched water table, no appreciable seedling heave or winterkill, and least dowel heave. No significant differences in amount of frost heaving of seedlings were noted amonga alfalfa cultivars on any drainage site. Highest dry matter yields were obtained on the well-drained Alford site; significant yield reductions occurred as soil drainage class became more poorly drained. Alfalfa stands were successfully established on the well-drained Alford series and the moderately well-drained Hosmer series. Soil drainage characteristics did influence alfalfa establishment and production in the climatic transitional zone of the central U. S. Poorly-drained soils should not be considered for alfalfa production.