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Since its introduction from Eurasia, smooth bromegrass (Bromus inermis Leyss.) has become an important cool‐season forage grass in North America. The objective of this study was to document breeding progress in smooth bromegrass between 1942 and 1995 in North America. Thirty cultivars or experimental populations were tested at up to seven sites in the eastern and central USA, with a range of soil types and climates. There have been small genetic changes in forage yield, brown leafspot resistance [caused by Pyrenophora bromi (Died) Drechs.], in vitro dry matter digestibility (IVDMD), and neutral detergent fiber (NDF) concentration. Brown leafspot resistance increased gradually, averaging 0.21 units decade−1. Mean forage yield did not change for cultivars developed after 1942, but was 0.54 Mg ha−1 (7.2%) higher for the post‐1942 group than in ‘Lincoln’, a direct representative of smooth bromegrass introduced into North America. Selection for increased IVDMD led to an average increase in IVDMD of 9 g kg−1 (1.4%), an increase in forage yield of 0.33 Mg ha−1 (5.0%), and a decrease in NDF of −8 g kg−1 (−1.2%) in the post‐1942 group. The slow rate of progress for smooth bromegrass forage yield is due to its complex polyploid inheritance, emphasis on traits other than forage yield, and relatively little concentrated attention from public and private breeders.

Use of tall fescue (Festuca arundinacea Schreb.) regrowth to extend the grazing season into late fall and winter is becoming increasingly popular in middle‐latitude regions of the USA. Few studies have been reported, however, that deal with factors influencing yield and quality of regrowth forage in winter. A field study was begun in October of 1971 to measure the effects of N, P, and K fertilization on yield and quality of tall fescue regrowth in late fall and winter. Eight fertility regimes were established in each of four replications. These were: 1) N applied at 60 kg/ha in spring and after each of three summer harvests, 2) P applied at 30 kg/ha in spring and in late summer, 3) K applied at 60 kg/ha in spring and in late summer, 4) to 7) the four possible combinations of the above three treatments, and 8) no fertilizer treatment. Forage from all plots was harvested in mid‐May, early July, and mid‐August and then in either mid‐December or mid‐January. In 1971 when the experiment began, all plots were harvested on 9 October rather than mid‐August and then in either mid‐December or mid‐January. Nitrogen fertilization increased yield and concentrations of in vitro digestible dry matter, total nonstructural carbohydrate, K, Mg, and N in the late fall and winter harvested forage and decreased concentrations of dry matter and Ca. Yield and concentration of quality components decreased less in N fertilized forage than in unfertilized and P and K fertilized forage as harvest was delayed from December to January. Phosphorus fertilization had little effect upon yield and quality components. Potassium fertilization decreased both Ca and Mg concentrations. Results suggest that winter forages of sufficient quality to meet most of the nutritional needs of many classes of livestock in mid‐latitude regions of the U.S. may be obtained by manipulating summer and/or fall harvest dates and fertilization rates. Supplementation of regrowth forage with Na and Mg and possibly with P during late winter months would be required.

Forage stockpiled in situ for winter use provides pasturage during a period of low forage production in midlatitude states of the midwestern and eastern United States. Two experiments were conducted to study the effects of harvest management and N fertilization rates on spring‐summer and autumn‐winter production of tall fescue (Festuca arundinacea Schreb.) forage. Treatments in Exp. I included four N rates; 0, 60, 120, and 180 kg/ha applied as NH4NO3 in split applications of one‐half in March and one‐half in August; three spring‐summer cutting schedules (1) mid‐June only, (2) mid‐May and early July, and (3) early June and mid‐July; and three autumnwinter harvest dates (1) mid‐December, (2) mid‐January, and (3) mid‐February. The soil was a moderately welldrained Lily loam (Typic Hapludults). Regression analysis indicated that the yield of forage available during winter increased as annual N application increased up to 137 kg/ha and 126 kg/ha for mid‐June stockpiling initiation in 1973–1974 and 1974–1975, respectively. The optimum annual N application rate for forage stockpiled beginning in early‐July was calculated to be 197 kg/ha in 1973–1974 and 136 kg/ha in 1974–1975. Stockpiled forage yields decreased from 2.50 metric tons/ha to 2.24 metric tons/ha between December and February averaged over the 2 years of the study. Winter in vitro digestible dry matter yield (IVDDM) decreased during winter. In Exp. II, treatments included four N rates: 0, 75, 150, and 225 kg/ha applied as NH4NO3 at the time of the last summer or autumn cutting which occurred in either early September, mid‐September, or early October. The soil was a Clarksburg silt loam (member of the fine‐loamy, mixed, mesic family of Typic Fragiudalfs). All forage was harvested in late winter. Forage yields during spring and summer increased up to the highest rate of N applied in both seasons. Any delay in initiation of stockpiling in Exp. II resulted in reduced winter yield. Winter yields increased in response to N application. Cutting date in autumn had little influence on forage yields the following spring, but rate of N fertilization did influence spring yield. Increasing autumn N application from 0 to 225 kg/ha increased spring forage production by an average of 2.40 metric tons/ha.