Wetland – Cattail



The sustainable transition in the Netherlands is in full swing and affects everyone, including farmers. A preliminary conclusion is that the farmer is no longer only responsible for our daily food but in the future will also become an important supplier of raw materials for the buildings we live in. Fibre crops such as cattail are indispensable for the production of insulation materials and composite products for the purpose of construction. The challenge is how to responsibly implement these crops in our current acreage and define their economic value. An important part of the value comes from the long term capture and storage of CO2 in our future biobased houses by utilizing these plants. These plant fibers allows us to build CO2 negative instead of emitting CO2. In this project, we describe the farmer not only as Food Farmer but also as Fiber Farmer. Farmers in the Netherlands have gone through several major transitions over the centuries and now too they face major changes to meet our climate goals. Our farmers need our support to make this transition happen in the coming decades.


For centuries the Dutch have been experts is controlling the water levels in our low lands. Land was reclaimed from the sea and repurposed for agricultural use. An intrigued web of small and large waterways with strategically placed pumping stations enables us to drain our lands to make them dry enough for our milk producing cows and high yield crops. One of the consequences of this de-watering is the drying out and lowering of our lands, and specifically also our peet deposits. By reducing the water levels in our peet soils we accelerate the oxidizing of these layers causing large amounts of CO2 to be released. Now the reduction of CO2 emissions is urgently required we are increasing the water levels in several areas in the Netherlands, in specific the areas adjacent to Natura 2000 reserves. A substantial amount of these lands are not suitable for traditional food or livestock farming. For these plots alternative crops are required. Wetland crops such as Pitre (Pitrus), Cattail (Lisdodde) en Reed (Riet) are very suitable for wet soils and have the benefit of extracting nutrients and excess phosphate from the soil greatly improving the quality of our surface waters which in turn will benefit biodiversity greatly. Studio Tjeerd Veenhoven (STV) is researching the value chain of wetland crops for over 8 years. Pioneering how to grow, harvest, process and apply these wetland fibers for building applications. Together with local stakeholders and with support from European and National innovation programs the potential of these crops is tested.



To build an average house like we have been doing for decades emits 40.000 kg of CO2. In the Netherlands the building sector is responsible for 11% of the national CO2 emission. Reducing emissions turns out to be problematic for this sector due to its complexity, revenue models and conventional culture. Small initiatives are happening and natural fibers are a large part of making reduction possible. A simple example is insulation to keep our houses warm (and cool). Currently we still mainly use petrochemical based insulation materials for this such as polystyrene or polyurethane, or energy intensive insulation like mineral wool. 1 kg of this insulation represents 1 kg of CO2 emission. When we insulate with natural fibers such as cattail we capture 1.5 kg of CO2. By changing to organic insulation we can reduce the CO2 emission of an average house by several tons. And perhaps even more important is that after use this organic insulation material does not pollute in any way and can be repurposed to similar or comparable building materials, prolonging the storage of this captured CO2 for a very long time.


Climate change brings a different weather type to the Netherlands, instead of the long mild showers in wintertime we now are faced with occasional downpours along with longer periods of drought. Water will become more precious and we have to rethink ways to store and maximize the use of water. These new weather models might push us to redefining the allocation of our soils by following the way of the water. Where possible water should be stored in nature reserves where nutrient levels are low and biodiversity can be secured. Via surrounding plots this water should slowly drain to various types of agro and forestry allowing for maximal utilization of water and soil. obviously, due to the large variety of soil types in the Netherlands, this model does not cover all our regions.


Hier moet nog een infographic onder. staat in de map, FarmerFiberValueChain, ook in de gallery

Materials, Research