Published online by Cambridge University Press: 12 June 2017
Chemical-fallow experiments were initiated as a possible means of improving summer-fallow procedures for seedbed preparation and rehabilitation of abandoned croplands subject to wind erosion. Red threeawn (Aristida longiseta Steud.) and sand dropseed (Sporobolus cryptandrus (Torr.) Gray) are pioneer perennial grasses that have stabilized these sandy loam soils but are undesirable forage plants. Dimethylarsinic acid (cacodylic acid), 2-tert-butylamino-4-ethylamino-6-methylthio-5-triazine (GS-14260), and a mixture of 3-amino-l,2,4-triazole (amitrole) plus ammonium thiocyanate were ineffective, but 2,2-dichloropropionic acid (dalapon) applied at 6 lb/A or more reduced these pioneer perennial grasses 80 to 100%. Follow-up treatments, either mechanical or chemical, are needed to maintain control of competing vegetation while seeded species become established.