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Two experiments were conducted between 1983 and 1985. In each case, timothy was established with or without barley, red clover, broadleaf weeds and grassy weeds. Four and six weeks after seeding, botanical composition, soil water-content, soil nutrient-content, light interception, and plant coverage data were obtained. The plots were then harvested once during establishment year and twice during subsequent years. At harvest, yield, botanical composition, and forage quality were obtained. Companion-cropping precluded forage cut during establishment and decreased forage yield during the first production year. Establishment with barley had little effect on forage quality but it favored the development of perennial broadleaf weeds. Inter-cropping with red clover decreased timothy yield but total forage production was increased and forage quality was improved. Red clover also reduced the development of perennial broadleaf weeds. The absence of broadleaf weed control increased productivity during establishment but timothy contribution was reduced and perennial broadleaf weeds development was accelerated. Perennial broadleaf weeds reduced yields during the first production year. Establishment without grassy weed control increased yield during establishment (but quality was lessened) and reduced it during the first production year. Establishment with grassy weeds had little effect on the weeds growing thereafter. In presence of both types of weeds, the grassy species were suppressed and the results reflected the situation observed in presence of broadleaf weeds. Finally, principal component analyses showed 12 factors that could be used to predict crop yield. The interpretation suggested that early measurements of weed density along with weed and crop coverage data would give good predictions of crop loss.

Numerous soil borne pathogens attack alfalfa roots and crowns and reduce stand longevity by predisposing plants to winter injury. Persistence can be improved by the use of cultivars with good disease resistance and by applying phosphorus (P) and potassium (K). The objective of this study was to examine the productivity and quality of alfalfa cultivars differing in disease resistance, under various fertilizer regimes on three different soils. A completely cross-classified factorial experiment in a randomized complete block design (RCBD) was established in 1990 with three rates of P (0, 33, and 66 kg ha$ sp{-1}$), three rates of K (0, 124, and 248 kg ha$ sp{-1}$), and two cultivars ("Apica" and "Oneida VR"). Treatment combinations were established (with 10% timothy, by seed weight) on three soils with distinctive drainage characteristics (referred to as ideal, intermediate and marginal). Disease ratings, stand counts, yields and herbage mineral content were measured in each of two production years. Yields and plant populations were the lowest on the marginal soil, while disease levels were the highest. Fusarium spp. were the most common fungal isolates from diseased roots and crowns at all sites. Apica tended to persist better than Oneida VR and have lower levels of crown and root rot. Neither P nor K had an effect on yield or persistence at the Ideal site, with positive responses noted on yield at the other sites. Potassium improved persistence at the Intermediate site and had variable but positive effects on disease levels. Increased rates of K fertilizer resulted in reduced herbage Ca, Mg, crude protein (CP) and increased herbage K and Acid Detergent Fibre (ADF) levels. Regardless of management, alfalfa production on soils with inadequate drainage remains risky.

There is little information comparing the impacts of bison and cattle grazing in the northern mixed-grass prairies; understanding which grazer to use for management is important. I collected data in sites grazed by bison or cattle using point counts to survey the songbird community, and habitat structure measurements. I used generalized- and non-linear mixed models to determine the relationships between grazers and habitat or songbird communities. Bison and cattle grazing caused changes in habitat structure, including decreased vegetation height and litter depth. Sprague’s pipits declined more steeply with bison grazing than with cattle grazing. 0.4 AUM/ha was an important threshold, because chestnut-collared longspurs increased in abundance at this stocking rate, and grasshopper sparrows decreased in abundance at this stocking rate. Either grazer is appropriate for managing for grassland birds. There is also an opportunity to encourage surrounding landowners to manage their lands for the benefit of wildlife.