http://hdl.handle.net/10150/635582 2026-05-10T17:01:35Z http://hdl.handle.net/10150/650496 Journal of Range Management, Volume 39, Number 1 (January 1986) Complete digitized issue. 1986-01-01T00:00:00Z http://hdl.handle.net/10150/645559 Small Mammals in Modified Pinyon-Juniper Woodlands, New Mexico Severson, K. E. The effects of pinyon (Pinus edulis)-juniper (Juniperus spp.) treatments on rodent abundance, 13 to 18 years after treatment, were studied in southwestern New Mexico from 1981 to 1983. Treatments included bulldozing, bulldozing/piling/burning, thinning, and untreated woodland. The area had not been grazed by livestock since time of treatment but was subjected to light and irregular use by wild ungulates. Total rodent numbers were significantly greater (P is greater than or equal to 0.05) on all treated areas compared to untreated woodlands but individual species and groups responded differently. Woodrats (Neotoma spp.) and brush mice (Peromyscus boylii) increased in abundance as slash accumulations increased, regardless of condition of overstory. Pinyon mice (P. truei) and rock mice (P. difficilus) numbers were also greater where slash was present, but only if the pinyon-juniper overstory was relatively intact. Grassland rodents, as a group, were more abundant on areas where the pinyon-juniper overstory and slash had been removed (bulldozed and bulldozed/piled/burned), but reduced numbers on bulldozed plots where slash was left suggested slash accumulations may have detrimental effects on numbers of these species. Treatments did not influence number of different rodent species. Data indicate that numbers of individuals and proportions of rodent species can be affected by manipulation of pinyon-juniper overstory and method of slash disposal. 1986-01-01T00:00:00Z http://hdl.handle.net/10150/645544 Renovation of Seeded Warm-season Pastures with Atrazine Dill, T. O.; Waller, S. S.; Vogel, K. P.; Gates, R. N.; Stroup, W. W. Numerous warm-season pastures have been established in the last 30 years in the central Great Plains. Some of these pastures are old enough to verify that they can be abused by overgrazing as easily as native tallgrass prairies. Overgrazed warm-season pastures are invaded and dominated by cool-season grasses such as smooth brome (Bromus inermis Leyss.) and Kentucky bluegrass (Poa pratensis L.), which diminishes the pasture productivity during the hot summer months. Since established warm-season grasses have greater tolerance to the herbicide atrazine than cool-season grasses, the effectiveness of atrazine applications in renovating invaded warm-season pastures was evaluated. A single, early spring application of atrazine (3.3 kg/ha) killed or sufficiently suppressed the cool-season grasses so that surviving warm-season remnants were able to effectively re-establish the warm-season pasture in a single growing season without any loss in total pasture forage production. Lower rates of atrazine were not as effective, particularly if smooth brome was the primary cool-season grass. The single atrazine application cost was approximately 25% of the seed cost associated with more conventional renovation. Pastures should not be grazed the treatment year but can be hayed at the end of the growing season. The success of the practice is dependent on the presence of warm-season grass remnants. Spraying test strips in small fenced areas would be advisable before treating entire pastures. 1986-01-01T00:00:00Z http://hdl.handle.net/10150/645543 Relationships of the Error Associated with Ocular Estimation and Actual Total Cover Hatton, T. J.; West, N. E.; Johnson, P. S. The relationship between the error associated with the ocular estimation of cover and the magnitude of actual cover was examined by estimation of artificially constructed images of known cover under laboratory conditions. Estimation error varied with actual cover in a manner suggesting that cover classes should be relatively narrow at the extremes of actual cover. 1986-01-01T00:00:00Z