Mineral nutrition of vegetable crops: XXV - Mineral nutrition of new zealand spinach plant (Tetragonia expansa Murr.)

The present work was carried out in order to study: a - the effect of omission and presence of the macronutrients and boron on the growth of the plants; b - deficiency symptoms of macronutrients, as well of boron; c - the effect of the deficiency of each nutrient on the chemical composition of the plants. Young spinach plants were grown in pots containing pure quartz sand. Several times a day the plants were irrigated by percolation with nutrient solutions. The treatments were: complete solution and deficient solution, in which each one of the macronutrients was omitted as well boron. Soon as the malnutrition symptoms appered, the plants were harvested and analysed chemically. - symptoms of malnutrition are easily observed for N, K, Ca and B. - symptoms of malnutrition for P, S and Mg are not easily identified. - the nutrient content, in dry matter, in deficient leaves and healthy leaves is:O trabalho teve como objetivo estudar alguns aspectos da nutrição mineral do espinafre (Tetragonia expansa Murr.) no que concerne: 1 - Efeitos da omissão dos macronutrientes e do boro, na obtenção de um quadro sintomatológico; 2 - Efeitos das carências na produção de matéria seca e composição química da planta. Mudas com trinta dias de idade foram transplantadas para soluções nutritivas carentes nos macronutrientes e/ou em boro. A coleta das plantas foi realizada quando os sintomas de deficiência se tornaram evidentes. No material seco procedeu-se a análise química. Os dados mostram que: 1 - os sintomas visuais de deficiência de N, K, Ca e B apresentam-se bem definidos; sendo que os de P, Mg e S são de difícil caracterização ; 2 - os teores dos nutrientes em plantas sadias e deficientes são

Training and Pruning Apple Trees

Training and pruning principles are discussed with the physiology of tree growth, northeast climate conditions, and growers' objectives in mind. Pruning and training of young, non-fruit bearing apple trees is discussed separately from pruning of fruit bearing trees. Mechanical pruning, renovating old trees, supports, scaffold limbs, central-leader development, and economics of pruning are covered

THE ECONOMIC IMPACT OF WILDLIFE DAMAGE ON HUDSON VALLEY ORCHARDS

The impact of wildlife damage on the profitability of apple farming in New York\u27s Hudson Valley was determined by vise of a Standard Net Present Value (NPV) analysis as a means to measure long-term impact. Data were gathered through questionnaire and interview of a stratified random sample of 39 growers that represented 17% of the regional growers. Data concerning species causing damage, extent of wildlife damage and types of controls used were combined with current and long-range costs including revenue lost through damage and control costs. Limitations of the analysis are discussed along with results that indicate an annual equivalent cost flow for all wildlife damage between $3.8 and$3.85 million or $184 to$188 per acre. This study shows that a typical grower experienced combined revenue losses and control costs of $12,500 during 1986. Fifty-two percent of this was associated with wildlife controls, 40$53 and $62 million depending upon whether a 3.5% or 5.0% discount rate is used

EFFECTS OF DIFFERENTIAL PINE VOLE POPULATIONS ON GROWTH AND YIELD OF \u27MCINTOSH’ APPLE TREES

Pine voles (Microtus pinetorum LeConte) were maintained as known populations (0, 269, 538 and 1075/ha) in wire mesh-enclosed blocks of \u27Mclntosh\u27/M26 apple trees (Malus domestica Borkh) for 2 years. There was little measurable effect of the voles on growth and production the 1st year, but during the 2nd year the highest population was associated with the death of one tree; severe reductions in growth, yield, and fruit size; a 78% reduction in crown bark weight, 56% loss of fibrous roots, and a dramatic reduction in the value of the crop. Although the low and the medium populations showed little effect on yield, there was a reduction in vegetative growth in the medium population plot that was associated with extensive root girdling, fibrous root reduction and substantial bark loss by the end of the 2nd year