Pinestraw harvesting is an important industry in the southeastern United States. There is a need to understand how fertilization can be used efficiently to sustain or increase long-term pinestraw yields and avoid adverse environmental consequences. The effects of fertilization on needlefall nutrient concentrations, pinestraw yields, and nutrient removals on soils with contrasting soil nutrient sorption potential (Entisol vs. Ultisol) were compared using two midrotation slash pine plantations in North Florida. Diammonium phosphate was applied at 0, 144, 430, or 718 kg ha^–1 in the spring of 2009 and 2010. Pinestraw was harvested annually in 2009–12. Needlefall mass, pinestraw yields, total Kjeldahl nitrogen concentrations in needlefall and pinestraw, and total Kjeldahl nitrogen, P, K, Ca, and Mg removals increased with fertilization. Diammonium phosphate at 718 kg ha^–1 year^–1 increased pinestraw yield over the control by 37 and 35 percent 2 years after the second fertilization, and by 11 percent (from 21.5 to 23.8 Mg ha^–1) and 12 percent (from 25.0 to 28.1 Mg ha^–1) over the 4-year control totals, at Entisol and Ultisol sites, respectively. Differences between sites were larger than fertilization response for most variables. Yields, nutrient concentrations, and removals were higher at the more fertile Ultisol than Entisol and, at both sites, higher than most reported in the literature.

中文翻译：

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佛罗里达州斜线松人工林中Pinestraw收获对养分的去除

松草收获是美国东南部的重要产业。有必要了解如何有效地利用施肥来维持或增加长期的针叶草产量，并避免不利的环境后果。在北佛罗里达州，使用两个中速旋转的阔叶松林比较了施肥对针耕期养分浓度，针叶草产量和土壤养分吸收潜力相反的土壤养分去除的影响（Entisol对Ultisol）。磷酸二铵的施用量为0、144、430或718 kg ha ^–1在2009年和2010年春季。Pinestraw在2009–12年度收获。针叶质量，针叶草产量，针叶和针叶草中凯氏氮的总浓度以及凯氏氮，P，K，Ca和Mg的去除总量随施肥而增加。718 kg ha – ¹年– ^1年的磷酸二铵在第二次施肥后2年比对照提高了Pinestraw的产量，分别为37％和35％，分别提高了11％（从21.5到23.8 Mg ha ^–1）和12％（从25.0％到25％Mg ha ^–1）。 28.1兆公顷^–1），分别在Entisol和Ultisol站点进行了4年的控制。对于大多数变量而言，位点之间的差异大于受精响应。肥沃的Ultisol比Entisol的产量，养分浓度和清除率更高，而且在两个地点均高于文献中大多数报道的水平。