1988-04-29_PERMIT FILE - C1981008A (55)

Home Browse Search

• • • Seedbed preparation is one of the most critical aspects in establishing irrigated pasture and hayland where high levels of productivity, quality, and utility are desired (Stewart 1973, Ensign et al. 1975, and Heath et al. 1985). The seedbed must be clean, weed -free, relatively smooth, and firm in order to properly establish the species to be irrigated. This relates to reduced competition from undesirable species, the critical need to place the seeded species at the proper seeding depths, and elimination of air pockets or zones that will result in seed dessication or poor soil moisture availability. Prior to final seedbed preparation, soil conditioning and weed control tillage will be carried out through the use of chisel plowing and disking. Chisel plowing will relieve any topsoil compaction, will aid in controlling weedy species, and will leave the site in a temporary roughened condition reducing wind and water erosion potential. Disking will be used to condition soil, break up clods, and control weeds through tillage prior to seeding. If annual weeds are a problem, several tillage operations may be required to get adequate control. Harrowing and cultipacking prior to seeding will be conducted as needed in order to provide the smooth, firm seedbed required. In any areas that may be poorly drained, tillage will be timed in order to reduce bogging, excessive compaction and excessive cloddiness caused by tillage when soils are wet. The best period for tillage in these areas may be in the early spring prior to the irrigation season (prior to mid - April). Tab 21 "Minesoil Reconstruction" contains additional information on subsoil and topsoil conditioning. Seeding will be done either with a cultipacker type seeder or a drill equipped with double -disk openers, depth bands, and packer wheels. A cultipacker may be used behind the drill to also firm the seedbed. Either of these two types of seeding equipment will provide the greatest level of success in terms of proper seed placement and firming of the soil around the seed. Seeding depths are usually about 1/4 inch deep for the species to be seeded, and never more than 1/2 inch deep. Seeding will primarily be done using the alternate row method where all grasses are seeded in every other row and the legume is seeded in the remaining rows. This method decreases competition, especially for species such as birdsfoot trefoil which can be somewhat difficult to establish and are poor competitors in the seedling stage. This method is an accepted method for establishing good pasture and hayland and will assure the desired proportion of grass and legume species over the life of the pasture or hayland (Dan Smith, personal communication, April 1988 and Ensign et al. 1975). Seed Mix #7 will not be as greatly affected by competition problems and may also be seeded with species in each row or may be seeded using the alternate row method. 22 -19 Revised 07/25/91