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 emissions1 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.
This trial will be one of the first in the UK and start to provide the data needed to assess the plant’s physical and financial viability.
‘Glyceria fluitans was chosen due to its long history of human consumption, high edibility and tolerance to a wide range of growing conditions. The plant has huge potential as a future high value food crop of the future’
This sweet nutritious grain has been harvested from the wild in the past from wetland habitats as a human food source. But the plant has never been domesticated due to the reduction in natural habitats. However it may be an ideal species to domesticate for a wet farming system. Literature also suggests that the straw is incredibly nutritious and therefore has potential as animal feed (fodder).
As a potential wet farm crop the benefits for Peat Restoration, Climate Change Control and Biodiversity will also be present. The crop can grow on both water covered and wet peat, which allows the rewetted peat to function effectively. Reducing carbon emissions and actively store CO2 contributing to the UK Carbon reduction target.
Crop Notes Floating sweet grass is a perennial herb of marshes, swamps and muddy pond margins and forms floating rafts in shallow water by ditches, rivers, ponds and lakes. It tolerates high levels of disturbance and nutrient-enrichment, as well as being found in a range of soil moisture conditions. Growing to approximately 95cm high, the above ground biomass is harvested, leaving the plant in the ground to regrow, no need for annual seed sowing.
This species produces the largest seed of the Glyceria family, with a nutritional content similar to that of conventional cereal crops and is less competitive than G. maxima. These attributes make floating sweet grass attractive as an ecological option for field trials and producing large edible grains.
Current seed availability is low, sold in small batches of seed (£2/200) to enthusiasts. From initial trial plots, sowing seed or as plug plants in Spring is currently the best option.
In another trial, a May planting of mature plants produced harvestable grain in August-September, indicating the possibility of a harvest in the first season. All of the planting and harvesting methods have been for experimental purposes.
We aim to investigate; the grain yield at a higher water table to inform future development as a food crop and biomass yield to inform other areas of use e.g fodder and bioenergy potential.
Other research gaps to be investigated are weed pressure and notable pest species which will influence future crop management choices, variation in time from planting to maturity and the potential harvesting methods. Mechanical harvesting with adapted machinery may be possible if the plant growth habit can be suitably manipulated through a plant breeding programme.
End Products/ Potential Markets Historical accounts and research provide the information on its uses. The grain can be turned into a flour or rolled as porridge style oats, and could be used as a seed for baking. It has been highlighted as a speciality of Polish cuisine by travellers visiting the country2. The flour or rolled grains were served in dumplings, flatbreads and in sweet cakes. Used in broths and soups, with butter or boiled milk, with oriental spices and had a use as a binding additive to sausages.
Food using the grain was recommended to patients with debilitating diseases and malnourished children3. Further investigation to establish the crop’s gluten free status could also increase its potential.
As a plant that can cope with moist, wet/flooded conditions, it could form part of a combined farming system for use on less productive areas of peatland or areas that are too wet for conventional crops but by adopting a wet farming system for the area it has the potential for wider benefits of crop income, payment for ecosystem services and environmental sustainability.
Key Points
G. fluitans appears to have good potential as a high value food crop
Data on the plant as a crop is very limited at present and more work is required to evaluate the crop potential.
A systematic breeding program will be needed to improve yield and growth habit for mechanised planting and harvesting systems.
Resources
Online Atlas of the British and Irish Flora –Glyceria fluitans, https://nph.onlinelibrary.wiley.com/doi/pdf/10.1002/ppp3.10070
Borrill, M., 1958. A biosystematic study of some Glyceria species in Britain, 4. Breeding systems, fertility relationships, and general discussion. Watsonia, 4, pp.89-100.,
References
1 W. Wichtmann, C. Schröder and H. Joosten (eds.) Paludiculture – productive use of wet peatlands: Climate protection – biodiversity – regional economic benefits. Schweitzerbart, Stuttgart. pp. 100- 101. (ISBN: 9783510652839)
2 Łuczaj, Ł.J., Dumanowski, J., Köhler, P. and Mueller-Bieniek, A., 2012. The use and economic value of manna grass (Glyceria) in Poland from the middle ages to the twentieth century. Human ecology, 40(5), pp.721-733.
3 Hozyasz, K.K., 2020. From rediscovered “niche” to “mainstream”–Glyceria fluitans as a candidate grain for manufacturing premium food products. Plants, People, Planet, 2(2), pp.104-106.