This information is from the fact sheets developed as part of the Water Works project
Paludiculture (Wet farming) is an emerging way of producing crops and resources on peat soils in a truly sustainable way. The benefit of this system is that it allows the peat to stay wet enabling it to store carbon and reduce greenhouse gas emissions (1) something that a conventional farming system cannot achieve on wetland soils.
As we learn about this wet farming system and suitable crops, the data will increase and knowledge will evolve. The information provided here is current and accurate at the time of writing and presented in good faith.
Common Bulrush (Typha latifolia)
Why grow this crop? Economic and Environmental Reasons
Markets are establishing in Germany and the Netherlands for Typha as a bioenergy crop and raw product for building materials. As interest in these markets grow so will the demand for Typha as the raw material increase. The UK is a new market and country for production.
The benefits for the Environment, Climate and Peat are equally important reasons to consider growing Typha. The crop will grow in peat with a higher water level, this means the peat will start functioning as it should; reducing the carbon emissions from the peat and the established plants will actively store carbon. Both actions contribute towards the UK CO2 reduction targets.
Typha plants remove nutrients from water. They can act as a sink for 30-60kg of Phosphorus per hectare per year. If a mosaic of crops was planned, positioning the Typha crop upstream as the first crop for water to pass through will improve water quality downstream and for crops requiring little or no nutrients, for example Sphagnum moss.
The Typha beds provide a good habitat for wetland wildlife and can contribute to developing the wider nature recovery network.
Crop Notes
Typha is a perennial crop growing from rhizomes and forms dense stands of plants. The plant is tolerant of a range of growing conditions and will grow on peatland that is no longer productive using traditional crops or farm systems.
Typha’s high productivity is very attractive: In a natural setting a yield of 3.58 to 22.1ton ha-1 can be achieved, with fertilisation, or enriched irrigation water higher yields up to 44.5ton ha-1could be possible.
The above ground biomass is harvested annually by cutting. The timing is dependent on the intended market and the balance between economic and environmental benefits wishing to be achieved.
Figures for set up and establishment of Typha beds are still estimates based on field scale trials. The type of plant material used to establish the crop and planting density has a strong influence on the overall cost. If basic land preparation, minimal irrigation requirements needed and low planting densities used the costs will be intermediate 3,000 to 5,000 euros/ha (£2729 to £4548/ha (4)) Cinderella project (5).
End Uses / Potential Markets
Bioenergy: Typha has a high calorific value for use in bioenergy applications, both direct combustion or for conversion into another fuel product. The calorific values are around 17 Mj kg-1 which is suitable for direct combustion as raw material or compressed into pellets.
Bioethanol production research in 2017 examined the potential for production of bioethanol from harvested Typha. The plant has a high cellulose content and a range of other features giving the plant significant promise as a raw material for bioethanol fuel production (3).
Building Materials: Typha is fast growing, and has high yields compared to forestry. The fantastic insulation properties of the crop mean that it can be converted into lightweight, moisture resistant insulation board e.g Typhaboard, or hollow fill insulation. Currently the UK is a net importer of fibreboard products, and imports up to 1/3rd of its particleboard needs, making a clear opportunity to increase production in the UK. It could also be used in the production of lightweight aggregates for improving concrete insulation values, and improved load bearing.
Supplementary food for Biological Pest Control predators Typha pollen has been found to aid the increase of certain predator species used for biological pest control (6).
Biodegradable Food Packaging in the United States where Typha grows in abundance is being wild harvested to be used as pulp for food trays.
Food Product potential, there are references to parts of Typha plants being used for human consumption and fodder. These do not appear to be as viable markets compared to the others mentioned above.
Key Points
Typha is increasingly becoming recognised as an agricultural crop (2)
Adapted planting and harvesting machinery already available
Harvesting time and cropping cycle is dependent on the end product and aims for the crop; economic, ecosystem services, biodiversity
Set up and establishment costs are dependant on site and conditions
Government subsidy or payment for ecosystem services is needed in the crop establishment period.
Typha farming information—Greifswald Moorwissen Centre https://www.moorwissen.de/en/paludikultur/projekte/prima/index.php Wetland Products https://www.wetlandproducts.com , Wetland Conservation Biomass to Bioenergy End User Report RSPB Sally Mills, DECC https://ecosystemsknowledge.net/
References
1 Wichtmann et al, 2016, 2 Geurts, Jeroen & Fritz, Christian. (2018). Paludiculture pilots and experiments with focus on cattail and reed in the Netherlands. 10.13140/RG.2.2.12916.24966. 3 Rebaque et al. (2017) 4 Exchange rate 29/09/2020 5 Cinderella Project https://peatlandworkshop.thuenen.de/fileadmin/peatlandworkshop/Presentations/Wichtmann_CINDERELLA_06122017.pdf 6 Samaras K, Pappas ML, Fytas E and Broufas GD (2019) Pollen Provisioning Enhances the Performance of Amblydromalus limonicus on an Unsuitable Prey. Front. Ecol. Evol. 7:122.doi: 10.3389/fevo.2019.00122