ABSTRACT

Climate change in Maine is characterized by increasing rates of warming temperatures and more intense rain events, which lead to altered growing seasons, earlier emergence of pests, increased seasonal drought and large crop losses. These changes have significant impacts on wild blueberry systems and make it more difficult for growers to manage this crop under increasingly unpredictable weather patterns. Mulching is a tool growers use to combat some of these challenges, but the comparative effects of wood mulch particle size in wild blueberry systems has not been studied. The purpose of this study was to determine the effect of wood mulch particle size on wild blueberry soil, plant development, pest pressure, and yield. This study was carried out over a 2-year period (one production cycle) in an organic wild blueberry field in Stockton Springs, ME. There was no mulch particle size treatment used in this study that demonstrated significantly greater overall mean soil moisture compared to the control at the 1.27 cm application thickness. All mulch treatments significantly reduced disease pressure, primarily Sphaerulina leaf spot caused by Sphaerulina vaccinii, compared to the control in year 1. The two finest particle size treatments, sawdust and shavings, resulted in significantly greater yields than the control, and were the least expensive materials. This suggests that growers should consider using finer particle size mulches rather than the current practice, wood chips, but may need to reapply more frequently. From this study, application of softwood mulch of any particle size is better than no application.

摘要

缅因州气候变化的特点是气温升高速率加快和降雨事件增多，这导致生长季节改变、害虫提前出现、季节性干旱加剧和农作物大量损失。这些变化对野生蓝莓系统产生了重大影响，使种植者在日益不可预测的天气模式下更难管理这种作物。覆盖是种植者用来应对其中一些挑战的工具，但尚未研究过在野生蓝莓系统中木材覆盖颗粒大小的比较影响。本研究的目的是确定木覆盖物粒度对野生蓝莓土壤、植物发育、害虫压力和产量的影响。这项研究是在缅因州斯托克顿斯普林斯的一个有机野生蓝莓田中进行的，为期 2 年（一个生产周期）。在本研究中没有使用覆盖物颗粒大小处理，与 1.27 cm 施用厚度的对照相比，总体平均土壤水分显着增加。所有覆盖处理都显着降低了病害压力，主要是由Sphaerulina vaccinii，与第 1 年的对照相比。两种最细粒度的处理，锯末和刨花，导致产量显着高于对照，并且是最便宜的材料。这表明种植者应考虑使用更细粒度的覆盖物，而不是目前的做法木屑，但可能需要更频繁地重新应用。根据这项研究，使用任何粒径的软木覆盖物都比不使用要好。