THE EFFECT OF POLYACRYLAMIDE ON GRASS EMERGENCE IN SOUTH-CENTRAL NEW-MEXICO

Seeding rangeland is a challenge for rangeland scientists, especially on those soils with tendency to crusting. Although some information is available on how soil conditioners affect emergence of certain comestible crops, little is known about the effect of synthetic organic matter on grass emergence. We examined the effect of polyacrylamide, a soil conditioner, on seedling emergence of blue panicgrass (Panicum antidotale Retz.), King Ranch bluestem (Bothriochloa ischaemum [L.] Keng), sideoats grama (Bouteloua curtipendula [Michx.] Torr.), plains bristlegrass (Setaria macrostachya H.B.K.), and 'salado' alkali sacaton (Sporobolus airoides [Torr.] Torr.) under field conditions. Emergence of blue panicgrass and sideoats grama was increased with polyacrylamide applications, even at the lowest concentration (10 kg ha-1) during summer 1987. No emergence response to polyacrylamide applications was found for King Ranch bluestem, and plains bristlegrass did not emerge in any experimental plots during summer 1987. During summer 1988, blue panicgrass and sideoats grama emergence was again increased with polyacrylamide applications. Emergence of 'salado' alkali sacaton and King Ranch bluestem was unaffected by polyacrylamide applications. Soil conditioners may be a feasible alternative for seeding some rangeland in areas where crusting is a problem.