To control weed competition in organic fruit orchards there are only few and expensive devices on the market. Alternatives with mulching methods or weed burners do satisfy only in specific conditions. Tillage systems that provide sufficient, reliable weed competition control over a large range of soil and site conditions and for low costs are still to be developed.
In order to ensure a sufficient supply of water and nutrients in orchards it is necessary to regulate weed growth in the in-row strips. In organic fruit growing this is achieved by keeping the soil open with special tillage equipment (very costs intensive), or by mulching with organic material, such as bark, wood shavings and straw (high costs and high deposition of potassium, which increase the risk of bitter pit) or water permeable synthetic ground covers. The mulching systems can considerably increase mice damage and are suited only for specific soil and site conditions.
i) to develop and validate an alternative system (Sandwich System) that allows a sufficient supply of water and nutrients, but needs a lower input of resources;
ii) comparing growth and yields of the trees under Sandwich-System versus usual tillage over the whole width of the tree strip.
The systems were compared in 7 apple cultivars. Two repetitions in each cultivar. Collected data was yield, trunk perimeter, nutrients contained in fruits and leaves (T-Stage). For the statistical analysis we used the Program JMP 4.02 (SAS incorp.), ANOVA model; variety, System, repetition, variety*system, variety*repetition, system*repetition
