ABSTRACTthan DM1 by ewes not supplemented with zinc methionine and ewes fed the 11.3% CP diet. Ewes fed the 14.9% CP diet tended ( P < .14) to gain more BW from 30 d prepartum to 4 d postpartum and lose more BW from 4 to 42 d postpartum than ewes fed the 11.3% CP diet. Ewes fed zinc methionine and the 14.9% CP diet produced more ( P < .lo) milk on d 28 than their counterparts. Ewes rearing twins produced more ( P < .05) milk on d 4, 10, and 18 than ewes rearing single lambs. However, milk production on d 28 was not affected by number of lambs reared ( P = .68). Lamb ADG at 28, 42, and 59 d postpartum was greater ( P < .05) for both the zinc methionine treatment and the 14.9% CP diet. Zinc methionine ( P = .11) and the 14.9% CP diet ( P = .02) increased weaning weights by 6 and 9%, respectively. We conclude that both the zinc methionine supplement and the 14.9% CP diet resulted in more persistent milk production. In addition, when ewes and lambs were fed for an average of 42 d during early lactation, a 14.9% CP diet, and to a lesser degree, a chelated zinc methionine supplement, lamb weaning weights were improved.

Legumes in cool‐season grass pastures can improve productivity and quality. In May of 1997 and 1998, a split‐split plot field experiment with six replications was planted in Morris, MN to evaluate the effect of sod suppression, planting method, and legume species on establishment of legumes into existing cool‐season grass pastures and to evaluate kura clover (Trifolium ambiguum Bieb.) and birdsfoot trefoil (Lotus corniculatus L.) as potential species for interseeding in the North Central region. Whole‐plot sod suppression treatments were (i) 0.62 kg a.i. ha−1 glyphosate [isopropylamine of N‐(phosphono‐methyl) glycine] or (ii) no glyphosate. Subplot planting methods were (i) no‐till drilling, (ii) broadcasting seed on the soil, (iii) broadcasting seed followed by harrowing, and (iv) broadcasting seed followed by a light disking. Legume species sub‐subplots were (i) alfalfa (Medicago sativa L.), (ii) red clover (Trifolium pratense L.), (iii) kura clover, and (iv) birdsfoot trefoil. Stand data were collected in the fall of the planting year and in the spring of the second growing season. Averaged across planting methods and species, legume stands were 38% where glyphosate was used and 3% where it was not. No differences or interactions were detected for planting method (P > 0.12). In this study, if competing vegetation was suppressed, stands were >31% regardless of planting method. When sod was suppressed, alfalfa established better stands than the other legume species. The overriding factor in the ability to establish legumes in this study was the suppression of existing vegetation during establishment.

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promise for longevity in pastures of the north-central USA (Sheaffer et al., 1992). Exceptional winterhardi-Legumes can improve productivity and quality of cool-season grass ness, tolerance to drought (Black and Lucas, 2000; Watpastures but often do not persist under grazing. In May of 1997 and 1998, field experiments were planted in cool-season grass pastures son et al., 1998), and tolerance to frequent defoliation near Morris, MN, to evaluate establishment and persistence of kura (Peterson et al., 2002; Peterson et al., 1994a) have inclover (Trifolium ambiguum Bieb.) compared with alfalfa (Medicago creased interest in the potential of kura clover as a sativa L.), birdsfoot trefoil (Lotus corniculatus L.), and red clover component in pasture-based livestock production sys-(Trifolium pratense L.) under grazing pressure in the north-central tems. These characteristics are linked to its extensive, USA. Each spring, from planting through 2002, stands of these leroot-rhizome complex (Peterson et al., 1994b). In Wisgumes were evaluated for persistence. Pastures were grazed five or consin, Holstein steers grazing kura clover/mixed coolsix times per growing season for 12-h grazing periods by lactating season grass pastures gained an average of 1.2 kg d Ϫ1 dairy cows (Bos taurus L.) over the duration of the study. Kura clover and more than 1000 kg ha Ϫ1 during 3 yr of rotational stand density was low relative to the other species in the growing stocking (Mourino et al., 2002). The consistently supeseason after establishment but increased and maintained denser stands in subsequent growing seasons. Alfalfa, birdsfoot trefoil, and red clo-

Diminishing availability and increasing costs of herbicides cause strawberry growers to seek both chemical and nonchemical alternatives, especially for within-row weed control soon after strawberries are transplanted. Several weed control treatments for strawberry establishment were examined during 2 yr in Minnesota. Treatments included: woolen landscaping fabric centered over the crop row; as above, but 2-ply fabric; spring canola incorporated into soil when 30 cm tall; as above, but canola killed with burndown herbicide and left as mulch; standard herbicide, DCPA; hand weeded; and no weed control. Areas between all strawberry rows were cultivated. Measurements included weed densities and weights, numbers of strawberry daughter plants, and fruit yield 1 yr after transplantation. The best alternative treatment was the 1-ply woolen fabric. It nearly eliminated weeds from rows, promoted daughter plant rooting, and allowed maximum fruit yields, equivalent to those of the DCPA and hand-weeded treatments. Canola mulch controlled weeds inconsistently and achieved only modest to low production of daughter plants and fruit. Weed control and fruit yield with incorporated canola were similar to the weedy check treatment.