Farm management

Farm management is currently very basic. There is a single farm manager instance that is in charge of all fields, and farms these either as grassland or arable land.

Grassland can be managed either extensively or intensively. Extensive grassland is mown twice a year, in late April and early September. Intensive grassland is sown once it is over 25cm tall (until the end of summer), which makes for five cuts a year. The proportion of meadows that are assigned to the extensive management can be set with the farm.extensivegrassland setting.

Arable land is farmed using a set crop rotation for all fields (by defaults: winter wheat, winter rape, silage maize, winter barley). At model initialisation, each field is assigned one crop from the rotation at random. The crop model determines when a field is ready to be harvested, after which it is re-sown with the next crop in the rotation. The farm.setaside setting determines what percentage of arable land is to be left fallow each year. If the current fallow area is smaller than this, the next field to be harvested is converted to fallow for one year.

Different scenarios can be programmed to modify this basic behaviour, or change parameter settings over time. For example, the "thuringian_fallows" scenario tracks the change in fallow area in Thüringen from 2000-2020 due to policy changes (3% before 2008, 0.5% from 2008-2014, 1.7% from 2015 on).