Can alfalfa stands be revived with a quackdigger?

Mike Rankin
Crops and Soils Agent
University of Wisconsin - Extension

        Remembering back to the big alfalfa winterkill years of 1992 and 1993, some producers remarked that thinned and injured alfalfa stands could be "revived" by pulling a quackdigger (field cultivator) across the field.    From an agronomic perspective, this practice makes no sense at all when the potential damage to crowns and roots is considered.

        Several years ago, an innovative graduate student at South Dakota State University somehow persuaded his major professor that this would be a good masters degree research project.  A deteriorating alfalfa field was used to impose spring treatments with a spike tooth harrow, spring tooth harrow, tandem disk, and a Triple K harrow.  Cultivation treatments were conducted in the early spring when the alfalfa was just breaking dormancy.  Yield, plant density, and weed density were measured later in the summer.  The results showed no significant differences between the cultivation treatments and the control plots (no cultivation done) for any of the criteria measured in either year.

        This trial showed that early spring cultivation of thinned alfalfa stands is not going to "revive" them into a significantly better stand than what you were dealt coming out of winter.  However, it also showed that the alfalfa plant is tough to kill even with some intense secondary tillage (Triple K harrow treatment).  It is not uncommon to see alfalfa bounce back quickly after being chisel plowed and without first being killed with a herbicide treatment.