The "network reference farms plant protection" is a joint project of the Federal Ministry of Food and Agriculture (BMEL), the plant protection services of the German States (Länder) and the Julius Kühn-Institute (JKI). However, the voluntary collaboration of the selected agricultural farms is of decisive importance for the success of the project.

The project is part of the National Action Plan on the sustainable use of plant protection products. It started in 2007. The target of the network reference farms contains two aspects:

1. The annual determination of the intensity of the usage of plant protection products (treatment index) with regard to specific fields respectively crops of the farm.
2. The technical evaluation of the determined plant protection intensity with the help of background information particularly regarding year-specific conditions.

The technical assessment of the plant protection intensity aims at assessing the necessary extent for each specific plant protection measure in the context of the concrete situation.

Corridors of the necessary extent of a specific year can be derived retrospectively from the data, the statistical analysis and the technological assessments. Furthermore, objective influences (for example weather conditions, pest occurrence, costs and revenues, counseling) and subjective influences (for example knowledge, risk behavior) on the intensity of the usage of plant protection products are identified with regard to regional or yearly specifics. In the long term these findings help to adjust the plant protection even more to the necessary extent and in general to the concept of integrated plant protection (IPS) while paying attention to regional specifics.

The plant protection institutions of the Länder in cooperation with the JKI organize and evaluate the data of the reference farms. Plant protection reference farms have been established in the following sectors:

• arable farming (winter wheat, winter barley, winter rape, partly also others),
• field vegetables (white cabbage, carrots, asparagus, onions),
• fruit growing (dessert apples),
• winegrowing and
• hop growing.

With regard to arable farming it was aimed for an even distribution of the plant protection reference farms to the survey regions arable farming (ERA) following Roßberg et. al (2007) and Roßberg (2008). In all survey regions at least three reference farms ought to be available with the crops winter wheat, winter barley and winter rape. With regard to all other product sectors all important growing regions of the respective crop ought to be represented as representative as possible.

The illustration demonstrates the distribution of the reference farms