About the project

Both one-, two- and perennial weed species can be challenges in grasslands, the perennials often being the most problematic. The perennials are divided into two groups, stationary (e.g. docks) and creeping species (e.g. couch grass).

In grasslands, stationary species are particularly common, and many consider the dock species to be the worst. Some keywords for undesirable aspects related to docks are: rejection on pasture, distaste of the feed and that they outcompete more valuable grassland species. The term 'docks' is often used as a species name, but there are often three species: curled-, broad leaved- and northern dock.

There are two distinctive features of dock biology that make it difficult to control: its vigorous tap root and its large, persistent seed bank. Direct measures against docks are carried out by mechanical or chemical fallow (clean-up) when renewing the grassland and by using selective herbicides in the established crop. Both intensive tillage and the use of herbicides raises concerns for the environment. Of preventive measures, a well-established crop, balanced fertilization and good soil structure are central. However, there the relationship between dock distribution and surrounding factors needs to be studied to reduce the necessity for direct measures.

To reduce the use of herbicides and tillage, the aim is to implement control measures only where necessary (e.g. spot spraying) and to develop integrated strategies to make alternative control measures more resource efficient.

SUSDOCK will contribute to this by: 1) Developing automatic, image-based mapping tools of dock species; 2) Generating new knowledge about the relationship between dock occurrence and explanatory abiotic and biotic factors; 3) Evaluating integrated strategies to control docks on grassland and during regeneration of grasslands with minimal tillage and use of herbicides; 4) Evaluating spot application of herbicides with new platforms such as (unmanned) drones and robots.

• Background

  Broad-leaved dock (Rumex obtusifolius) and curled dock (Rumex crispus) are some of the most problematic weed species in grasslands worldwide; joined, in Norway and the rest of Northern Europe, by the far less studied northern dock (Rumex longifolius) (Ringselle et al. 2019).

  Docks reduce the quality and yield of grassland crops by outcompeting higher yielding and more nutritious crop plants (Zaller, 2004). Furthermore, docks contain substances that are unhealthy for livestock if consumed in high doses (Rahman et al., 2013).

  Docks develop taproots that provide them with an advantage over grassland crops once the docks are established, and dock seeds can live for several decades in the soil, enabling docks to take advantage of openings in the grassland sward. Thus, without intervention, docks tend to increase as the grassland ages. In addition to grassland, docks can cause problems in other crops that use grass strips between the crop plants, such as fruit and berries.

• Objectives

  Primary objective Develop sustainable weed management and image-based mapping of docks (Rumex spp.) in North European grasslands.

  Secondary objectives:

  • 1. Develop automatic image-based mapping and targeting of dock species that is adapted to Norwegian grasslands.
  • 2. Generate new knowledge about the relationship between dock occurrence and explanatory abiotic and biotic factors on Norwegian farms.
  • 3. Evaluate integrated strategies for controlling docks in grassland and during grassland renewal with minimal tillage and herbicide use.
  • 4. Evaluate spot-application of herbicides by new platforms like unmanned aerial sprayers and robots.
• Participants

  NMBU participants

  PhD. student Kim Bredesen
  Prof. Nils Vagstad
  Dr. Olav Martin Synnes

  External participants

  Dr. Björn Ringselle, RISE - Research Institutes of Sweden (WP3 leader)
  Dr. Therese W. Berge, NIBIO - Norwegian Institute of Bioeconomy Research.
  MSc.
  MSc. Ragnhild Borchsenius, NLR
  MSc. Sara Hansdottir, NORSØK
  MSc. Martha Ebbesvik, NORSØK
  MSc. Kari Løe, NORSØK
  Simen Skjønsberg, Kverneland Group Operations Norway AS
  Atilla Haugen, BIODRONE AS