Root distribution in fruit orchards with conservative soil management

Soil conservation through an agro-ecological approach is fundamental in modern and sustainable fruit production. A vegetal cover of the soil has multiple advantages, it limits soil erosion and nutrient leakage, ameliorates the soil structure and microporosity, reduces soil temperature, increases soil water retention and soil organic matter content. Moreover, it enhances the whole orchard biodiversity maintaining a higher number of herbaceous species and macro and micro flora and fauna and providing additional agro-ecological services. However, management needs to be carefully studied because the vegetal cover can be a competitor to the fruit tree for water and nutrients. In particular, the presence of herbaceous species will influence root development, growth, distribution and function. This is particularly important in modern fruit orchards, where tree densities are increasing, and roots systems have a smaller soil volume to be explored. The alternate use of different soil management techniques has been tested in a biodynamic farm in central Italy and, in the present study, the distribution of tree root system was evaluated. A yearly rotation of spontaneous cover, shallow tillage, cover crop and green manure lead to different root distribution and depth in the inter-row, with a more homogeneous root distribution where aerating grassing was applied.