Years in pasture is the number of years the block is in pasture in the 10 year period before the Reporting year and Year 1.
This is important because of the increased accumulation of organic matter that occurs under pasture rotations. The years in pasture is used to modify the N mineralisation rate, which has significant consequences for N cycling.
A year in pasture is defined as at least 8 months of the year in continuous pasture.
- 0 years indicates a continuous cropping regime. This includes years when, for example, a block is in crop for 10 months and in pasture for two months.
- 10 indicates perennial pasture with no cropping during the period, this includes cut and carry blocks.
- The timing of cropping phase is ignored. Thus if over the 10-year period, 5 years in crop + 5 years in pasture, or 5 years in pasture + 5 years in crop, or 3 years in pasture, 2 years in crop, 2 years in pasture + 3 years in crop are all counted as 5 years in pasture.
- Even in the most extreme case, i.e. one year crop, one year pasture, one year crop, one year pasture etc. for the 10 year period; this should still be entered as 5 years in pasture. The comment from PFR regarding this is "Years in pasture is basically the number of years in the last 10 that the crop has been in pasture. In reality the proximity of those years to the current would matter but there is not good data to discern this effect...".
- Several paddocks with different years in grazed pasture (including cut and carry) may be
blocked together when other management factors are similar, Paddocks can be grouped when
years in pasture is consistent with these groupings: 0–2, 3–5, 6–8, 9, 10 years in pasture.
- For long-term pasture (> 6 years), intensive cultivation will result in more mineralisation than minimum tillage and this should be taken into account when blocking.
- Clover seed and ryegrass seed blocks should be counted as pasture.
- For fruit crop blocks, Years in pasture is set to 6 if the block is cultivated at establishment,
and 2 otherwise.