In the core areas of National Parks (NPs), there might be a conflict between the approaches of process-based conservation, i.e. allowing natural ecological processes to develop without intervention, and of species-based conservation, i.e. active management to protect specific aspects of biodiversity. To better understand this conflict and its consequences, we collected data on non-native plant species (neophytes) managed in 12 German terrestrial NPs and the measures implemented to control these in the period 2006–2016.

Based on this, we developed a decision-making process to identify the criteria that should be considered when determining the appropriate management of neophytes. This process considers the distribution of the species in the NP, age and zone of the NP, parameters for success, the degree of threat posed to local conservation goals by the species, and suitability of the measure.

The application of this decision-making process to existing neophyte control measures showed that 18 of these measures should be continued, six should be adapted and three terminated. In the examined NPs, there is often no evaluation of performance against their stated goals in neophyte management. For most measures, their efficacy remains unclear.

Preventive measures against neophytes are only carried out in four of the 12 NPs investigated here. Given that NPs have the goal of protecting ecological processes, this lack of preventive measures is critical. Especially in this category of protected area, avoiding the introduction of neophytes in the first place can significantly reduce the need for control and eradication measures later.

A conflict of objectives between process-based and species-based conservation approaches currently exists in more than half of the NPs investigated here. The decision-making process does not resolve this conflict, but it does make the decisions more transparent and thus more communicable. By collecting and analysing the individual species-specific measures, it will be possible to reduce the number of measures in the future, thereby at least reducing the existing conflict of objectives. Promoting the protection of ecological processes for inherent reasons and following an actualistic interpretation of naturalness can improve the acceptance of neobiota in NPs.