No abstract

Gophers reduced forage production by 18 to 49% on sands and silty range sites in western Nebraska. Determination of percentages of the soil surface that were bare, covered by litter, and occupied by plant bases showed that gopher-disturbed areas contained greater percentages of bare soil and litter than did undisturbed areas. Basal cover of vegetation was highest on undisturbed areas. Frequency of vegetation on gopher mounds of different age was determined. Most perennial grasses increased in frequency on mounds with increasing mound age, while annual grasses and forbs decreased.

No abstract

Abused rangelands dominated by introduced cool-season gmsses and warm-season shortgrasses are common over much of the Mixed Prairie. Native decreaser species are primarily warm-season grasses and are present at only hwigniflcant levels on abused rangeland in the Loess Hills of southcentral Nebraska. A single, Iatespring, prescribed fire was evaluated as II method of improvement. The study area consisted of 3 tracts of plots located on Holdrege silt loam soil (Typic Argiustall) with an average annual precipitation of 550 mm. The vegetation on the tracts was in low range condition, with cool-and warm-season components being present in varying proportions on all tracts. In general, the dominant cool-season species were Kentucky bluegrass (Poa pratensis) and annual bromes (Bromus spp.), and the dominant warm-season species were blue grama (Bouteloua gracilis) and buffalograss (Buchloe dactyloides). Burning reduced the basal cover and herbage yields of cool-season species. This favored the warm-season component. The increaser short grasses generally exhibited higher herbrge yields and basal cover on burned as compared to unburned plots. These results indicate that a single, late-spring, prescribed bum may have a limited potential as a range improvement practice in the Loess Hills of south central Nebraska.

Rangeland grasses are difficult to establish on sandy soils because blowing sand can kill young seedlings. Four grass species, sideoats grama [Bouteloua curtipendula (Michx.) Torr.], cane bluestem [Bothriochloa barbinodis (Lag.) Herter], green sprangletop [Leptochloa dubia (H.B.K.) Nees], and sand bluestem (Andropogon hallii Hack.) were grown in a greenhouse and subjected to wind and wind with sand in a laboratory wind tunnel. The blowing sand killed the seedlings or retarded their growth, but wind alone had little influence. With increasing age, the young grass plants became more tolerant to wind and sand damage. Plant growth was slowed because the blowing sand ruptured plant cells, dried out the exposed tissue, and exposed the damaged seedlings to diseases and insects.