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To study the influence of understory vegetation management and fertilization, on pine growth and competing vegetation, a field trial was established in a 6-year old pine forest. Treatments included: control (C), vegetation cutting and removal, with and without fertilization (CRF and CR treatments), vegetation chipping, with and without fertilization (CDF and CD treatments). Treatments were replicate three times and arranged in completely randomized blocks. Pine volume was determined between 2002 and 2007 and understory was surveyed, quantified and analysed for macronutrients in 2002 and 2003. Vegetation chipping plus fertilization lead to the largest (p < 0.05) increase in pine volume (9.6 m3 ha–1 year–1) while removal of understory resulted in the lowest (p < 0.05), 5.1 m3 ha–1 year–1. In the other treatments, the average increase in volume was similar (6.4 m3 ha–1 year–1). When understory was removed nutrient output was rather large, especially the N output since Ulex minor was in 2002 the dominant species (65%). CD treatment was the most effective in reducing understory biomass (–76%), followed by CR (–65%), CDF (–57%) and CRF (–46%) treatments. In Control, vegetation biomass increased 48%. These results indicate that removal of understory without fertilizer addition is not a suitable practice. Chipping of vegetation besides avoiding nutrient output, decreased the amount of fuel, hence decreases fire risk, and if used with fertilizers leads to a significant increase in pine growth.

Since ryegrass (Lolium sp.) is a widely grown cool-season forage grass, its magnesium concentration is of special interest to ruminant livestock producers. This study was conducted to investigate the effect of calcitic or dolomitic lime addition on dry matter yield and mineral composition of hybrid ryegrass, Lolium (multiflorum x perenne x perenne) grown in eight acidic soils. Each soil received two levels of calcitic or dolomitic lime, L(C 1 ) and L(C 2 ) or L(D 1 ) and L(D 2 ), which raised pH to approximately 5.3, and 6.0. Dry matter yield response was obtained only in soils having an initial % Al saturation 59, % Mg saturation 10 and % Ca saturation 21. Only in one soil, which had an initial exchangeable Mg level of 0.05 cmol c /kg of soil, was response to dolomitic lime higher than that obtained with calcitic lime. Magnesium concentration in dry matter was increased by both levels of dolomitic lime with the increase dependent on the rate used and on the initial level of exchangeable Mg. The average Mg concentration increased from 0.8 to 3.9 g/kg, from 1.6 to 3.6 g/kg, and from 2.6 to 3.9 g/kg, when ryegrass was grown in soils having low, medium, and high initial exchangeable Mg levels, respectively. Mg concentration in the ryegrass tended to be lower in the unlimed soils than when calcitic lime was used, 1.1 vs. 1.4 g/kg, when the soils had low to medium exchangeable Mg levels. The results suggest

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