Implementation of trees in new paddock designs for outdoor sow herds can benefit the environment, economy and animal welfare
The Danish outdoor sow herds are efficient systems with low antibiotic usages and an important brand for Danish organic agriculture, but high risk of nutrient losses from the pastures challenge the production. A part of the solution is to implement trees in the paddocks, but inventive thinking regarding the paddock design and management is needed to increase the economic and environmental benefits of the trees.
A new research project, OUTFIT, is using four case studies to examine how paddocks with trees can be designed to meet diverse producer objectives and production conditions.
Hestbjerg Økologi (1450 sows), Risbjerg Landbrug (300 sows), Solhøjgård Økologi (160 sows) and Trynen i jorden (50 sows) and the project group are designing new paddock concepts, integrating trees in the design. Subsequently these novel designs are implemented at a minimum of two farms.
What trees to plant and how the implementation in the paddocks can be designed to ensure practicality are being considered at all four farms. Project coordinator Anne Grete Kongsted from the Department of Agroecology is emphasizing: “it is important that the selection of trees and the design are well considered before planting the trees, since – of course - they cannot easily be (re)moved afterwards”. Hence, this process can be time consuming.
Reduced loss of nutrients and increased area value
OUTFIT is going to examine how the implementation of trees in the new paddock designs can reduce the loss of nutrients and whether it is possible to harvest and ensile green tree biomass with nutritional value for pregnant sows. Different species of willow and poplar are examined in relation to production of biomass and the nutritional value of this. Furthermore, different methods for silage-production are investigated.
The project is also exploring whether it is possible to capture soil nitrogen in the so-called “nutrient hotspots” where the pigs prefer to eliminate. Anne Grete Kongsted explains: “to reduce the loss of nutrients from the hotspots, woodchips or sawdust from the trees will be applied to “capture” the nitrogen through the decomposition of the carbon from the wood. Quality, amount and timing is to be examined.”
Difficult decisions must be made
One of the challenges of the project is to consider all relevant parameters of creating the best design. Anne Grete Kongsted elaborates: “It is a challenge to obtain simultaneous low nutrient losses, a thriving biodiversity and producing a high-quality silage for the sows. Exemplified some willow species are favorable from an environmental perspective but not optimal for feed, since the taste - from the pig perspective - is less good than other willows.”
Animal welfare is the starting point
Anne Grete Kongsted explains how trees and animal welfare is coherent: “Animal welfare can be considered as a starting point for planting the trees, because the trees reduce the risk of heat stress by providing shade and a cooler microclimate – just as the trees are proving a natural diverse environment for the sows. With OUTFIT we are aiming to optimise what else these trees can by used for to consider the environment, biodiversity and farm economy.”
Inspirational catalogue for the farmers
When the research experiments are finished some of the outputs are an inspirational catalogue and fact sheets with information about the complete process including the choice of trees, location of these, regulation, weed control and so on. The project hopes to inspire and support more pig producers to establish trees in their paddocks.
OUTFIT is a part of the Organic RDD 6 program, coordinated by ICROFS (International Centre for Research in Organic Food Systems). Supplemented by The Green Development and Demonstration Programme (GUDP) under The Ministry of Food, Agriculture and Fisheries of Denmark.
Aarhus University (Dept. AGRO, FOOD, ANIS), Innovation Centre for Organic Farming, Organic pig producers: Hestbjerg Økologi & Risbjerg Landbrug, Danish Technological Institute, Center for Frilandsdyr, Ny Vraa Bioenergy