In many situations autumn‐saved pastures offers an excellent alternative to more traditional and expensive livestock programs where hay or silage are the main winter feeds. Environmental conditions during the period of fall forage accumulation are markedly different from those of the spring and summer months and both forage yield and quality were affected. The objective of this research was to study the effects of temperature and nitrogen fertilization on the growth and quality of autumn‐accumulated forage. Two field experiments were conducted during 1970–71 on a Beltsville silt loam soil (Typic Fragiudults) to measure the influence of N rates and soil temperatures on the growth and quality of autumn‐saved ‘Ky‐31’ tall fescue (Festuca arundinacea Schreb.) and ‘Potomac’ orchardgrass (Dactylis glomerata L.). Nitrogen was applied at either 0, 50 (1970 only), or 100 kg N/ha in late September. In 1971 soil temperatures were maintained at ambient and approximately 12, 20, and 27 C during the autumn using specially designed field equipment. Forage samples were collected from randomly‐selected, previously unharvested areas. These were separated into green, dead, and miscellaneous fractions for yield and quality evaluation. Tall fescue was a more suitable species for autumn‐saved pasture primarily due to its superior growth compared with orchardgrass. Differences in quality were not consistently found between the species. In November of each year, dry matter availability reached a maximum of approximately 4,000 and 3,300 kg/ha for tall fescue and orchardgrass, respectively. During December under ambient conditions net loss of dry matter occurred in both species, presumably due to a greater rate of leaf death and decay than leaf growth. Digestibility and protein percentages decreased only slightly during autumn. The minimum IVDMD and crude protein levels measured during approximately 100 days of accumulation in either year were 80 and 13.5% for tall fescue and 73.0 and 15.2% for orchardgrass, respectively. Nitrogen fertilization stimulated growth of the autumn‐saved pastures and also tended to increase crude protein percentages. An application of 100 kg N/ha in late summer produced up to 50% more dry matter by early winter than zero N. IVDMD of the forage was not affected by N fertilization. Growth of the grasses during fall was stimulated by increasing the soil temperature. This effect was greater for tall fescue than orchardgrass. Plant quality was only slightly affected. However, the relative effects of the soil temperature treatments in relation to air temperatures and light parameters were not determined.

This paper reports the findings of a five-year study on the growth patterns, production and means of persistence of white clover in a cool temperate environment with summer dominant rainfall, on the Northern Tablelands of New South Wales. White clover essentially persisted as a perennial, but large and rapid declines in plant frequency occurred during late summer if soil moisture levels became depleted. The critical combination of conditions at which plant frequency was adversely affected occurred when available soil moisture levels declined below 35 mm and mean weekly maximum temperatures exceeded 20�C; conditions which often occur in late summer in this environment. During one prolonged period of moisture stress in the second spring and summer period of the study, all plants died. Regeneration was due to germination of seeds and seedling establishment, but plants subsequently persisted as perennials. Relationships were developed to predict the probability of survival of white clover over the range of temperatures and soil moistures recorded in these experiments. Germination occurred to a variable extent each year, but was observed only during winter and spring. Seedling establishment was effective in only one year, which followed the death of white clover in summer, 1980-81. The sward was slow to recover after seedling regeneration owing to low winter temperatures and competition from established temperate perennial grasses in spring. Seedlings contributed little to dry matter production in spring. These results indicate that white clover is unlikely to be of value as an annual in temperate pastures. Strategies aimed at improving white clover in cool temperate environments, either by management or selection/breeding programs, should therefore focus upon improving the ability of white clover to persist as a perennial.

The practice of accumulating late summer and fall forage growth for winter pastures is growing. As temperatures drop in the fall, and as growth rates decline, the percentage of dead leaf material increases. The effects of reduced growth rates, and increased leaf senescence, has a pronounced effect on the quality of accumulated forage. The objective of this research was to determine the relationship between dead leaf content and whole plant digestibility of autumn‐saved forage. Field experiments were conducted during 1970–71 on a Beltsville silt loam soil (Typic Fragiudults) to determine the influence of N application and soil temperature on leaf deaths, fiber components, and quality parameters of autumn‐saved ‘Ky‐31’ tall fescue (Festuca arundinacea Schreb.) and ‘Potomac’ orchardgrass (Dactylis glomerata L.). Nitrogen was applied at either 0, 50 (1970 only), or 100 kg N/ha in late September. In 1971, soil temperatures were maintained at ambient and aproximately 12, 20, and 27 C during the autumn using specially designed field equipment. Forage samples were collected from randomly‐selected, previously unharvested areas. These were separated into green and dead leaf fractions and analyzed for fiber components and quality parameters. Neither forage species, N application, nor soil temperature greatly affected neutral detergent fiber, acid detergent fiber, lignin, or silica contents of autumn‐saved forages. However, there were trends for high fiber and lignin contents in plants grown on high soil temperature plots and for increased fiber content with time during autumn and early winter. Green leaves had lower levels of neutral and acid detergent fiber, lignin, and silica than dead leaves. During autumn and early winter, the proportion of dead leaves in the pastures increased from approximately 20 to 46% in both years; IVDMD of the green leaf fraction decreased slightly during this period from 89 to 85%. In the dead leaf component, IVDMD remained at approximately 67% in 1970 but increased from 60 to 75% in 1971. Relationships were developed for both years which showed that IVDMD of the pastures decreased by 3.38% (r = −0.8477, P 0.001) and 1.0% (r= −0.3147, P 0.05), respectively, for each increase of 10% in dead leaf content. The data indicate that caution should be exercised when using dead leaf percentages alone to predict forage quality of fall‐saved pasture; instability in the IVDMD of the dead leaves appears to be a major factor.

The herbage mass and relative growth rate of six perennial native grasses were compared with two introduced temperate perennial grasses (Phalaris aquatica L. cv. Sirosa, Festuca arundinacea Schreb. cv. Demeter and the temperate legume, white clover (Trifolium repens L. cv. Haifa). Of the native grasses three were year-long green species (Danthonia linkii Kunth, Microlaena stipoides (Labill) R.Br., Poa seiberana Spreng), and three were summer-growing frost susceptible species (Themeda australia (R.Br.) Stapf, Sporobolus elongatus R. Br., Bothriochloa macra (Steud) S.T. Blake). The summer perennial species, in particular Bothriochloa, were highly productive. However, in addition to inability to produce or retain green herbage during the winter, the summer-growing perennials produced a lower proportion of leaf material, a feature likely to render them less acceptable for grazing. Themeda was an exception, and produced a high proportion of leaf throughout the growing season and retained green material longer into the winter. Among the yearlong green species, both native and introduced, Poa proved a most productive species with significantly higher green leaf production than any other species, both in terms of herbage mass and relative growth rate. Although Danthonia produced as much herbage as phalaris on an annual basis, it has a higher stem component overall, and its relative growth rate was higher in the warmer months and lower during the winter months. Only Poa, white clover and phalaris produced signficant amounts of herbage during the winter months. These data suggest that native species have valuable agronomic features which could be exploited by selection and plant breeding programmes to advantage by the grazing industry.

A census of pasture types and their composition and attributes (e.g. purpose and carrying capacity) was carried out throughout southern Australia from June to October 1994. This paper describes the survey process and subsequent creation of an Australian temperate pastures database. Data were created for 562 local government areas (LGAs) from ‘desk estimates’ by trained agriculturists. They identified about 2500 pasture types, which were grouped into 120 standardised pasture categories. Some findings from the data are identified, namely the high relative importance on an area basis of unimproved native pastures, the importance of weedy species (e.g. Vulpia), and the marked decline with increasing rainfall in importance of annual medics compared with subterranean clover. This paper provides examples of the data and their use for assessment of the regional economic impact of increases in productivity of pasture species.