Inorganic Nitrogen Levels and Nitrification Potential in Lowbush Blueberry Soils

Effects of gypsum on yield and nutrient status of native lowbush blueberry

“…Hall et al (1982), however, in a study comparing the influence of five weather variables on blueberry production in eastern Canada, noted the difficulty in closely relating fruit production to weather conditions due to differences or variation in blueberry physiological development. Further to this, fertilization studies with lowbush blueberry are characterizedby inconsistent responses of fresh fruit yields to nutrition additions (Smagula and Hepler 1978;Trevett 1982;Eaton 1988 Townsend and Hall (1970), except for Fe which was low'…”

Denitrification in Lowbush Blueberry Soils

“…tND, not determined. Knowles (1982 (Eaton and Patriquin 1988) lead to subsequent increases in denitrification. According to Bremner and Shaw (1958) …”

“…Since the development of selective herbicides for low-bush blueberries (Yarborough and Ismail 1985), nitrogen-containing fertilizers, including ammonium nitrate, have been routinely applied to blueberry stands at rates of [35][36][37][38][39][40][41][42][43][44][45][46][47][48][49][50] kg N ha-', usually every second year (Trevett 1962). Repeated fertilization with nitrogen stimulates nitriffing activity even at the low pH levels (4.0-5.5) characteristic of these soils (Eaton and Patriquin 1988). One possible result of these higher nitrate levels is the potential for increased nitrogen losses via denitrification.…”

Long-term effects of herbicide and fertilizers on lowbush blueberry growth and production

“…Lowbush blueberry systems exhibit some characteristics more similar to forest systems than to tilled agricultural systems (Eaton 1988). tmportant features associated with nitrogen fertilizer applications to blueberry include: lorv rates of soil nitrification (Eaton and Fatriquin 1988) and denitrification (Eaton and Fatriquin D89), slow rates of organic matter decomposition (Stevenson 1986) , and internal translocation of nitrogen from one plant part to another in autumn and early spring (Chapin 1980;Heal et al 1982 (Yarborough et al 1986).…”

“…Fruit production of the lowbush blueberry is influenced by both management and environmental factors over the 2-yr production cycle. Management factors include pruning, weed, insect and disease control, irrigation, and fertilizer applications (Hall et al 1979;Blatt et al 1989 Commercial producers routinely fertilize blueberry stands following pruning, even though fertilization does not produce consistent increases in fresh fruit yields (Cain and Eck 1966;Smagula and Hepler 1978;Eaton 1988 All plots were burn pruned in May 1979, 1981,1983, 1985, 1987 and 1989. Fertilizers were applied by hand, at the rate of 56 kg N ha-l, to 5-m x 10-h plois. Fertilizers and herbicides were applied to all plots except burn-only controls in May of the prune year.…”