Tiller counts - 2020

Sampling was conducted in Kematen in Tirol, Austria, where spring barley (Hordeum vulgare L.) was grown in six fields that have had organic management for the past ten years, three in 2020 and 2021, respectively. Each field was split in half, one side being fertilized with manure and the other remaining unfertilized, as a negative control. The manure treatment was independently applied by each field’s respective owner, at a standard rate of 1.5 metric tons (1 500kg) per hectare, using manure spreaders, after tilling and pressing the soil. Four 5x5m plots per treatment were delimited, to carry out all sampling. These plots had no barriers or fences surrounding them that would impede or limit movement between the inside of the plots and the rest of the field area. Additionally, the plots were at least 5m from the field edge, to avoid edge effects. They were at least 10m way from each other along the field’s width, and between 15 to 20m along the length of the field. To avoid any spillover of treatment effects, plots were set at least 25m away from the border between the two treatments within the same field.
Sampling was conducted every two weeks, with one week of sampling and one of rest. The sampling period started on the 21st of April and ended on the 14th of July in 2020, while it started on the 3rd of May and ended on the 16th of July in 2021, to encompass almost the entire crop season. This resulted in seven sampling time points for the first year and six for the second.

Transects were carried out along the outside border of the plots (5m), to avoid trampling on the inside, collecting 30 individual barley plant tillers to count the number of aphids per tiller.