Cattail Production Chain Development

in Northeast Friesland

Cattail Cultivation Consultancy

March. 2015

Academic Consultancy Training (YMC-60809) Period 3-4, 2015

Project 1482 Program Better Wetter Cattail Production Chain Development in Northeast Friesland

Commissioner: Rianne Vos Knowledge Centre Northeast Friesland

Cattail Cultivation Consultancy

Manager: Lisanne van Beek Secretary: Denys van den Berg Controller: Wenyan Zheng Member: Xueyuan Leng, Maarten Verhoog, Egbert Bernard Wesselink

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Summary In this report, we identified the whole production chain of cattail in Friesland. We selected three species, which are suitable for cultivation and production, from the approximately 30 species in the Typha genus. The growing conditions of T. latifolia, T. angustifolia and T. × glauca were investigated. Based on the cattail growing conditions and actual situation in Friesland, we investigated the natural locations and recommended several locations for cattail cultivation. Furthermore, we visited a growing location in Friesland and designed an artificial growing bed for a pilot project. Harvesting is also an essential section in this production chain. We studied and compared suitable harvesting methods in costs, advantages and disadvantages. Production is the section that makes cattail raw material into high-value products. We focused on bio-laminate and insulation material. The uses and production processes of these products were investigated. To identify the market we investigated the product price, market size, market demand and product advantages of bio-laminate and insulation material. We also compared cattail based products with traditional products in their current markets and made an assessment and give recommendations on cattail based production. Additionally, the farmers are essential stakeholders in this production chain. Hence, we also studied the impact of introducing cattail cultivation on local agriculture in Friesland.

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Table of Contents

1. Introduction ...... 1

2. Cattail cultivation ...... 3 2.1. Growing conditions ...... 3

2.1.1. Typha latifolia...... 3 2.1.2. Typha angustifolia ...... 3 2.1.3. Typha glauca ...... 4 2.1.4. Growing conditions of the three species ...... 5 2.2. Growing locations ...... 5

2.2.1. Friesland ...... 5 2.2.2. Northeast Friesland ...... 8 2.2.3. Veenwoude ...... 9 2.3. Artificial growing beds ...... 10

2.3.1. Conditions for suitable locations of the artificial growing beds ...... 10 2.3.2. Design of artificial growing beds ...... 12 2.3.3. Design of artificial growing bed for Northeast Friesland ...... 13 2.3.4. Expected yields ...... 15

3. Harvesting methods ...... 17

4. Production and processing of bio-laminate and insulating material ...... 21 4.1. Using cattail for Bio-laminate ...... 21

4.2. Using cattail for insulation material ...... 22

4.2.1. Products ...... 22 4.2.2. Production Procedure ...... 23

5. Market Identification ...... 25 5.1. Insulating Material ...... 25

5.1.1. Market Volume ...... 26 5.1.2. Price Comparison ...... 27 5.1.3. Reasons for Minor Market Importance of Insulating Materials ...... 28 5.1.4. Assessment of cattail as source for insulating materials ...... 28 5.1.5. Recommendations cattail as insulating material ...... 29 5.2. Bio-laminate ...... 30

5.2.1. Market situation ...... 30 5.2.2. Cattail based floorings ...... 31 II

5.2.3. Recommendations cattail in laminate floorings ...... 32

6. Impact of cattail cultivation on agriculture situation...... 33 6.1. Actual farming situation in Northeast Friesland ...... 33

6.1.1. Actual farming situation in Northeast Friesland ...... 33 6.1.2. Introducing cattail as growing alternative ...... 34 6.2. Model calculation cattail cultivation ...... 34

7. Discussion ...... 37 7.1. Growing conditions ...... 37

7.2. Growing locations ...... 37

7.2.1. Provincial scale ...... 37 7.2.2. Regional scale ...... 38 7.2.3. Veenwoude ...... 38 7.2.4. Natural locations ...... 38 7.3. Artificial growing beds ...... 39

7.4. Harvesting ...... 40

7.5. Market identification ...... 40

7.6. Cultivating cattail on agricultural land ...... 41

8. Conclusion ...... 43

9. References ...... 44

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1. Introduction For more than a thousand years most of the lowland areas in the Netherlands, located in the western and northern part, were peatlands. Peatlands had an important role in environment and resource management issues (Charman, 2002). In the past, peatlands were used for water management in the Netherlands (Moore & Bellamy, 1974), by providing a location to store access water. Nowadays however, only a few paltry residues of this landscape remain. As a consequence, more and more water has to be pumped elsewhere during winter time. This is also the case for Friesland, a province of the Netherlands (see Figure xx, the squared area). Research data show that, until the 1960s a total of 100.000 ha were flooded regularly during winter time (Better Wetter, 2013). The corresponding wet conditions of flooding, a result of high precipitation events and a limited amount of drainage, control the existence of peatlands. The type of a peatland is defined by two fundamental factors: source of nutrients and source of water. These factors have contributed to the fact that in Friesland two types of peat can be distinguished. Bogs are ombrotrophic peatlands dependent on precipitation for water and nutrient supply, whereas minerotrophic peatlands are reliant on groundwater for water and nutrient supply (Holden et al., 2004). Bogs are therefore highly acidic (pH <4), while minerotrophic peat are less acidic. The problem of a decrease of peatlands in Friesland, along with a decline in water storage capacity, has become more urgent in recent years, despite attempts to counteract this decline. This problem began after a change in water management after the 1960s and still exists in Friesland. The artificial lowering of the water tables led to degradation of the peatlands by oxidation and a loss of their reservoir functions (Wösten et al., 2008). This management involved draining 98% of the originally flooded pasture areas by means of ditches to allow cultivation of these lands. An additional consequence of the drainage practices is that these areas became prone to subsidence as more and more of the peat soils are oxidized. In order to maintain the agricultural function of subsiding land the water board continuously lowers the water table, following the subsidence of the land. The areas in which these continuous draining practices were performed are now among the lowest areas in the Netherlands, at an average of about four meters below sea level, as illustrated in Figure 1.

Figure 1: Elevation map of the Netherlands, and zoomed in part of Friesland, in meters The current water management strategy is unsustainable and insufficient to keep up with the effects of climate change, especially with an expected future rise in sea level (Better Wetter, 2013). The researchers of Kenniswerkplaats Noordoost Fryslân and consultancy office for ecology Altenburgh

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& Wymenga acknowledged this problem in the low-lying areas. With their program Better Wetter they are looking for sustainable solutions to solve the following two problems in Friesland: 1) the subsidence of peat soils and 2) the flooding of areas during winter time. A solution for these problems is to restore and/or maintain the wetlands in Friesland. Hence, specific parts of land are planned to be flooded yearly. Most of the interesting areas for flooding are currently being used by dairy farmers as grassland (Venema et al., 2009). When flooding their land, the farmers will earn significantly less money off their lands and are therefore probably not willing to participate in this project. Hence, some kind of compensation is required. With the conflicting interest of farmers and the program of Better Wetter, an interest has arisen in the possibilities to economize vegetation in wetland areas. From previous ACT researches, Typha (cattail) was considered as one of the most promising water tolerant plants (ACT, 2013). Cattails tolerate high water levels and contain valuable raw material that can be used in the production of high quality products. However, few people have experience with cultivating cattail in Friesland or using the material for the production of marketable goods. Hence, information about cultivating cattail under Dutch conditions and its applications is needed. That is why our group Cattail Cultivation Consultancy (from now on referred as Triple C), an independent consulting group from Wageningen University, is going to explore the proposed idea to economize vegetation in wetlands by cultivating cattail in Northeast Friesland in this report. An attempt is made to develop a theoretical model for growing cattail under environmental conditions present in Friesland, along with a production chain for cattail. In a later stage, the model should be put into practice. In the process of developing a production chain, the following chapters are included in the report: · Chapter 2: Investigation of cattail growing condition, identification of growing, location in northeast Friesland, and a design of an artificial growing bed; · Chapter 3: Comparison of harvesting methods; · Chapter 4: Illustration of production process for two valued cattail based products; · Chapter 5: Identification of the market; · Chapter 6: Assessment of cattail cultivation on current agriculture practices.

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2. Cattail Cultivation Throughout the world a variety of different species of cattail are found (Murkin and Ward, 1980). In order to cultivate cattail in Northeast Friesland an assessment is required to identify the most adequate cattail species. In addition, suitable locations have to be identified where cattail can grow. For the determination of suitable locations databases on soil properties, water levels, salinity, and a digital elevation map of the Netherlands are used. On the one hand there is a possibility that cattail already grows at the identified suitable locations. On the other hand there is an opportunity to cultivate cattail artificially here. Creating artificial cattail cultivation areas requires an approach that will be discussed in this chapter. First of all, a description of the growing conditions of different cattail species, which can be grown in Northeast Friesland, is given. Afterwards, growing locations will be presented by means of a suitability map created for the area of Northeast Friesland. Finally, this chapter ends with a design for artificial growing beds for cattail. 2.1. Growing Conditions There are three cattail species that are suitable for cultivation in the Northeast of Friesland. These candidates, along with their environmental growing conditions, will be introduced below. 2.1.1. Typha latifolia Typha latifolia (T. latifolia) is a cosmopolitan aquatic plant occurring in wetlands through most temperature zones in North and South America, Europe, Asia and Africa (Global Invasive Species Database, 2011). Its preferred habitat includes slightly brackish marshes and a variety of freshwater systems with slow-moving water. T. latifolia can grow up to 1-3 m height, and it has 12-16 linear and flat leaves with a width that ranges between the 15 and 25 mm (Grace and Harrison, 1986). Its unisexual flower consists of a pistillate and a staminate portion, which forms a continuous spike with a diameter of 12 to 35 mm. T. latifolia can reproduce by either seeds or rhizomes. The rhizomes are the organs that have the longest life cycle. They have the potential to remain viable for as long as 17-22 months (Westlake, 1968). New stalks sprout from the underground rhizomes, leading to expansion of the population, and can cover an area of up to 54 m2 within two years with a total rhizome length of 480 m (Holm et al., 1997). T. latifolia can grow in various soil types and it is tolerant of both acid and alkaline conditions (Gucker, 2008). Water depth is a key determinant of the establishment and persistence of T. latifolia. Optimal water level tends to be high enough to submerge the lower parts of the plants, while low enough to prevent interference of photosynthesis and respiration of the leaves. Experiments showed T. latifolia performed optimally when established in a 22 cm deep pond (Grace, 1989). 2.1.2. Typha angustifolia Typha angustifolia (T. angustifolia) is a slender aquatic plant distributing throughout the temperate northern hemisphere, which usually grows in marshes, wet meadows, fens, estuaries, bogs, ditches, and along lake shores. T. angustifolia can grow up to three metres tall. It has an unbranched and round stem and linear leaves with a width ranging between the 3-12 mm. The inflorescence is a thin but dense cylindrical spike of stamen above a similar spike of pistil, with a gap of approximately 10 mm between the two. Large amounts of small pendulous seeds with a narrow embryo can be produced (Rook, 2004).

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T. angustifolia prefer a soil pH above 5.5, and are absent from more acidic soils. The optimal water depth ranges between the 50 and 80 cm (Grace and Wetzel, 1982). The primary means of colonization is by seed. Once established, further spread is achieved by vegetative reproduction (Grace and Wetzel, 1982). 2.1.3. Typha glauca Typha glauca (T. × glauca) is a hybrid which is commonly found in the areas where its parents T. latifolia and T. angustifolia are present. T. × glauca has characteristics intermediate to its parent species (Kronfeld, 1889; Grace and Harrison, 1986). It can grow up to three metres and its leaves can attain a leaf width similar to T. latifolia (Kuehn et al., 1999). The plant is highly sterile due to few or no seeds or viable pollen grains are produced. As a result, the reproduction occurs primarily through vegetative spread (Smith, 1967; Grace and Harrison, 1986; Larson, 1993). Table 1: Characteristics and growing conditions of three cattail species

T. latifolia T. angustifolia T. × glauca

Flower shape

Characteristics 1-3 m 1.5-3 m 1-3 m Stem height (Grace and Harrison, (Grace and Harrison, (Grace and Harrison, 1986) 1986) 1986) Broad and thin Narrow and thick Broad Leaves shape 15-25 mm 4-14 mm 5-19 mm (Weeda et al., 1994) (Weeda et al., 1994) (Kuehn et al., 1999) Vegetative Fast Faster than T. latifolia Fast reproduction (Selbo et al., 2004) (Selbo et al., 2004) (Smith, 1967) Sandy, silty, clay Peaty Similar to its parents Soil type (Gucker, 2008) (Bolen, 1964) (Smith, 1967) Not very tolerant, only Not very tolerant, slightly more than especially when Salt tolerance mildly brackish Lack of data germinating conditions are tolerated (Choudhuri, 1968) (Crain et al., 2004). 5.5-8 6-8.5 pH tolerance Lack of data (Weeda et al., 1994) (Weeda et al., 1994) No Yes Yes Wave tolerance

Growing conditions Growing (Weeda et al., 1994) (Weeda et al., 1994) (Smith, 1967) 50-80 cm 15-50 cm Water depth Peak density at 80cm (Grace and Wetzel, Lack of data (above surface) (Grace and Wetzel, 1982) 1982)

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2.1.4. Growing Conditions of the Three Species Table 1 gives an overview of the three cattail species listed above, which allows for the comparison of the characteristics and growing conditions of T. latifolia, T. angustifolia and T. × glauca. From the table it’s clearly seen that T. latifolia and T. angustifolia occupy similar habitats, although T. angustifolia is more tolerant of deeper water and saline soils than T. latifolia. This makes T. angustifolia more competitive than T. latifolia. The hybrid T. × glauca is tolerant to a variety of water depths and salinity levels. According to the study of Dubbe et al. (1988), T. latifolia has a shoot biomass of 4.7 Mg/ha while T. angustofolia has a biomass of 8.1 Mg/ha under identical field conditions, indicating a higher biomass production for T. angustofolia than T. latifolia. Besides, in another study a higher yield is observed for T. × glauca (14.8 Mg/ha) than T. angustifolia (11.7 Mg/ha). Therefore, it can be concluded that under similar conditions T. angustifolia and T. × glauca are more productive than T. latifolia. Due to these findings it can be concluded that T. angustifolia is the optimal species for this program. The main arguments are its higher overall biomass production, tolerance to saline conditions, resistance against uprooting by waves, higher tolerance for high water levels and its size of the leaves. The last reason is of importance since smaller leaves are easier to process. 2.2. Growing Locations The specification of the growing locations is divided into several classes, based on the scale involved. First a rough overview of suitable locations is given for the entire province of Friesland. Next, a more detailed map for only the north-eastern part of the province is shown and finally a map with recommended locations for the current testing area, near Veenwoude, is presented. All selections and classifications in the different maps are based on the growing conditions listed in the previous chapter. 2.2.1. Friesland

Figure 2: Suitability map for cattail. Source: own design

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Figure 2 is the map of the entire province of Friesland and is divided into several suitability classes ranging from very suitable (1) to not suitable (4). This classification is the result of combining maps for soil types (Figure 3), water tables (Figure 4) and salinity (Figure 5) in Arcmap (ESRI, 2013). Due to formatting and access restrictions only the soil type map could be loaded into Arcmap. Still this is not a problem since the attempt is to give a rough indication of suitable locations for cattail to grow. Because of a high correlation between the different soil types and the water tables and salinity the soil types have been used as a proxy.

Figure 3: soil map of Friesland. Source: Liedekerke et al. (2006), own design The main soil types present in the province of Friesland are Histosols, Fluvisols and Podzols (Figure 3) (IUSS WRB, 2006). Histosols are soils consisting mostly of organic matter, in this case peat. Fluvisols are young soils consisting mostly of fresh sediment deposited by the sea or a river. Podzols are well drained acidic older soils which mostly consist of poor sandy material. Based on the previous chapter the first two soils are ideal for cultivating cattail, while the Podzols are not suitable at all because of the lack of nutrients, low pH and good drainage. The water levels of the different locations is represented in the water table map (Figure 4). When comparing this map with the soil type map a strong correlation between the blue colours, indicating a high water table throughout the year, and the presence of Histosols can be observed. The same is true for the green and brown colours and Fluvisols and yellow colours and Podzols. Since cattail will be most productive in very wet areas this makes the locations with Histosols more suitable than Fluvisols.

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Figure 4: Water table map of Friesland. Source: BIS (2015)

Figure 5: Map of locations with possible salinity problems. Source: Wetterskip Fryslan (2015) Finally the salinity map (Wetterskip Fryslan, 2015) indicates that the northern part of the province at times experiences high salt loadings in its surface water. T. angustifolia can cope with slightly saline conditions, but it performs better in non-saline waters. This is why the northernmost Fluvisols are considered less suitable than the rest of the Fluvisols. 7

Combining these three maps results in four different suitability classes. All of the Histosols are most suitable due to their year round high water tables and an absence of salinity problems. Because the total area of Histosols is already quite large it was decided to only include those areas of the northeastern part that contained Histosols. This selection also included the test site near Veenwoude (section 2.2.2). 2.2.2. Northeast Friesland The map of Figure 6 is created by combining various sections of the AHN (Actueel Hoogtebestand Nederland), a digital elevation map of the Netherlands with a five meter resolution (AHN, 2015). The elevations in the map are in relation to NAP (Normaal Amsterdams Peil) which is equal to the average sea level. Only those sections of which a significant part was identified as a Histosol in the provincial map were included. Since the areas indicated as most suitable for cattail, the red circles, are also the lowest positions in the landscape this map can also be seen as an inventory of suitable locations for long term water storage. As can be seen in the map there are several areas with elevation minima (the dark blue areas). Currently these areas are lakes and therefore are good locations to start with when looking for more space for water storage since the surrounding land will generally be lower than average. This is especially true for the experimental location near Veenwoude, the large black circle, which is why that location will be covered in more detail.

Figure 6: Elevation map of North-east Friesland, with circles indicating suitable locations and the Veenwoude area. Source: AHN (2015) No further investigative research has been done for the rest of NE-Friesland for a number of reasons. It is possible to calculate the amount of water that could be stored, by raising the water level everywhere to one meter below NAP. However, the results would not be applicable to reality as it would disregard the presence of roads and houses. These are landscape elements that should remain above water level. For this a distance of one metre is incorporated. By combining a road and building database this obstruction could be accounted for, but then another limitation becomes apparent. Even within the relatively flat Friesland there are still large differences in elevation. A relatively high position in one polder will be equal to the lowest position in another one. For each polder or set of polders the maximum amount of water stored will have to be calculated separately 8 since it depends on the lowest landscape element which should remain above the water. Even then this approach requires even more fine-tuning since the elevation of surrounding polders should also be taken into account. If the water level is higher in one polder than in one near it, the higher water level will cause an increase in the amount of seepage into the polder with less water. This in turn requires more pumping, which is desired to be reduced. As a result of these obstructions the map only shows a broad overview of the Histosols in the NE- region of Friesland. All of the obstructions are taken into account in the more detailed map of the Veenwoude area and will be mentioned again when they are dealt with. 2.2.3. Veenwoude

Figure 7: Elevation map near Veenwoude. Source: AHN (2015) As seen in Figure 7, the site near Veenwoude is the largest low lying area in NE-Friesland and is already being used for alternative land management, in this case nature development. This means there will be less resistance against flooding the area. During a field visit to the area Triple C has observed that the entire area is surrounded by roads and that these roads are the lowest landscape elements present. The lowest location with a road that was identified is located at 65 cm below NAP. The lowest positions in the neighbouring areas are at 190 cm below NAP, but from the field visit we know that during winter time these locations are flooded. The lowest neighbouring locations that remain dry during winter time are at 150 cm below NAP. This is the maximum water level used to calculate the available area, since it would lead to the least amount of seepage into adjacent polders and because there would still be a safety margin of 85 cm compared to the lowest road segment. This is estimated to be the minimum safety margin.

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The cattail plants will be cut off at the maximum water level (50 cm above the surface) and should be able to tolerate the highest water levels during winter. This means all positions with an elevation between 200 cm below NAP and 150 cm below NAP are available for cattail cultivation. In Table 2 the elevation of every 25 m2 cell within the area is shown, divided amongst different elevation classes. By combining their surface areas with an estimation of the expected yield it is shown that for the current demand the experimental site near Veenwoude would be able to produce enough biomass. As can be seen in Table 3, the total water storage available in winter is about 265000 m³. Table 2: Cellcount and surface area of elevation classes within the area of interest Elevation class (m below NAP) Cellcount (-) Surface area (m2) 2.30 – 2.10 3657 91425 2.10 – 1.90 9831 245775 1.90 – 1.70 22708 567700 1.70 – 1.50 25183 629575 1.50 – 1.30 13838 345950 1.30 – 0.80 5872 146800 0.80 – 0.65 698 17450 0.65 – 0 2057 51425

Table 3: Water storage capacity at 50 cm of water Elevation class (m below NAP) Surface area (m2) Water storage (m3) 2.30 – 2.10 91425 63998 2.10 – 1.90 245775 122888 1.90 – 1.70 567700 17031 1.70 – 1.50 629575 62958 Total storage 266875

2.3. Artificial growing beds For the procedure of identifying suitable locations for artificial growing beds in Northeast Friesland several case studies about cultivating cattail elsewhere in the world are used. Several case studies will be described in this section to explain where artificial growing beds can be located in Northeast Friesland and how these growing beds are to be constructed. 2.3.1. Conditions for suitable locations of the artificial growing beds Case studies illustrated in this section, about constructing artificial growing beds to cultivate T. latifoloa and/or T. angustifolia, have in common that the construction has a strong linkage with constructing wetlands. Degraded sites, where current practices have disrupted natural vegetation patterns and altered the soil pH and fertility status (Sistani et al., 1999), are selected to re-establish terrestrial vegetation by means of cultivating cattail there (Slayden and Schwartz, 1989). As an additional consequence, the total surface area of the wetlands is increased by these measures. Hence, cultivating cattail in constructed wetlands provide great opportunities for the aims of the program Better Wetter to prevent even more subsidence of the land where paltry residuals of former peatlands remain, and to increase the water storage capacity of soils in Northeast Friesland. The artificial wetlands offer several advantages when compared to natural systems, including greater flexibility in sizing and site selection, and greater operational control for scientific testing (Gersberg et al., 1984). Although cattail is able to grow on soils with different textures (see section 10

2.1), it is advised to construct the artificial growing beds mostly in the areas of Northeast Friesland where the paltry residuals of peat are still present. Most studies about cultivating cattail and using to restore degraded wetlands focus on peatland areas (Podschlud et al., 1988; Holden et al., 2004; Wild et al., 2000). As Holden et al. (2004) explain, this is due to the presence of a residual layer of peat required to restore wetlands. Hence, the best chance for cultivation and recovery is where the slightly humified peat layer is still intact (Podschlud, 1988). Wild et al. (2000) have investigated the influence of cultivating cattail on a degraded wetland. Both T. latifolia and T. angustifolia were cultivated and seemed well suited to fulfil the important functional objectives for peatland restoration. Because of their physiological constitution; cattail is able to utilise the high nutrient potential. Even under waterlogged conditions it can tolerate continuous flooding (Brix, 1993). Hence, both cattail species were able to build up closed stands within a year, which led to extensive water retention possibilities and allowed for the simulation of a water regime typical for peatlands (Wild et al., 2000). Only in recent years researchers have considered approaches using buffer zones outside the area of peat and began to think about integrated catchment management. The research of Sistani et al. (1999) is a good example of this. Here, a wetland was established on former infertile soils with a low pH. Such conditions make it difficult to re-vegetate with terrestrial species. Still, T. latifolia was able to grow there. Sistani et al. (1999) showed that T. latifolia has an influence on the biochemical composition taking place in the soil. Within 3-4 years the constructed wetlands had taken on the biochemical characteristics of natural wetland. They were able to further alter the area by replacing the topsoil in combination with liming and fertilization. These measures are usually necessary for reclaiming and establishing cattail (Sistani et al., 1999). A second requirement to cultivate cattail (in a degraded peatland) is the need of a water source (e.g. a lake or drainage canals). In aquatic plant communities a high water-level is a key factor structuring not only vegetation zonation (Seabloom & Van der Valk, 2003), but controlling invasions of wetlands by supporting or hindering seedling establishment (Boers et al., 2007). Additionally, restoring peatlands by means of new peat formation is only achievable with waterlogged conditions and active re-wetting (Wild et al., 2000). Special attention has to be paid for correcting the water level in restoring former wetland sites that were used as agricultural land after drainage (Brülisauer and Klötzli, 1998). The water level should be raised up to the soil surface (Pfadenhauer, 1991). In Figure 2 an overview is given of suitable locations where natural or artificial growing beds for cattail are or could be located. At the moment it is unclear where cattail is currently growing in the province of Friesland. That is why, at this moment, it is not possible to make a distinction between natural stands or artificial growing beds. Additional research is needed to identify locations where cattail is currently growing. Hence, one map has been created that covers all suitable locations (Figure 2). In Figure 6 the most suitable locations for constructing artificial growing beds in Northeast Friesland are the blue coloured areas; the areas where paltry residuals of peat remain and high water levels (throughout the year) are present. One should keep in mind that (after locating natural stands) for every suggested suitable artificial growing location criteria like fen depth, presence of peat at depths of less than one metre, damage/threats to the wetland, and a hydrological analysis together with consideration of

11 appropriate options for remediation should be assessed before cultivating cattail (Pfadenhauen and Grootjans, 1999; Holden et al., 2004). 2.3.2. Design of artificial growing beds For the procedure of cultivating cattail in artificial growing beds, two scenarios are possible: 1) cultivating cattail in areas where a sufficient amount of peat has remained, called repairing of earlier impacts, or 2) cultivating cattail in a severely degraded wetland where all functions of a wetland have been lost and the wetland must be rebuilt (Wheeler, 1995). Still, all these approaches have in common a basic pattern of rewetting and increasing species diversity (Pfadenhauen and Grootjans, 1999). Without an additional influx of water with the ionic composition required for the survival of characteristic wetland species, constructing artificial growing beds is impossible. For scenario 1 the blocking or backfilling of ditches or drainage systems is sufficient enough to increase the water level at or slightly above the soil surface. As for scenario 2, effective rewetting leading to peat accumulation can only be accomplished by flooding (Pfadenhauen and Grootjans, 1999). This additional water has to be brought in from other areas (Brülisauer and Klötzli, 1998; Pfadenhauen and Grootjans, 1999). The procedure illustrated in this chapter of how to construct an artificial growing bed is based on the methodology of a research of purposes Wild et al. (2000) and Heinz (2011) where T. latifolia and T. angustifolia were successfully cultivated in constructed wetlands, formally used for agricultural. Figure 8 illustrates the design of such a constructed wetland.

Figure 8: An example of cattail growing bed design. One pump as water input and one leaky tube as water output are designed to keep the water level fixed at 20 cm. The total area is 1.4 hectare, surrounded by dams. This growing bed is also designed with access roads. Source Pfadenhauer et al., (2001) These constructed wetlands were built as a pilot demonstration site, situated in southern Germany in a fen area called Donaumoos. The system design of the constructed wetlands corresponds to an

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‘‘emergent macrophyte-based system with surface flow’’ as described by Brix (1993). The building procedure started out by removing the topsoil and creating dykes from the material. With a possibility that during the summer Northeast Friesland may suffer from the consequences of a large precipitation deficit, it is important to store large quantities of water in the winter by setting dams as high as possible even at the risk of widespread flooding (Dietrich et al. 1996; Pfadenhauer and Grootjans, 1999). The basins were supplied with nutrient rich water. This water was pumped from drainage ditches, using borehole pumps, which flow through an underground pipe system to shafts enabling water inflow rates to be measured. Here, water inflow had a permanent flow rate to fix the water levels throughout the year. Holden et al. (2004) state that once peat start to regenerate it will eventually become self-sustaining and artificial water tables will no longer be needed. For future practices more research is needed on the stability of cattail stands. Peat formation in the constructed wetlands should be monitored with the attempt to identify stable wetlands which are able to cope with natural water level fluctuations without affecting the growth process of cattail. In the research of Wild et al. (2000) and Heinz (2011) a total of 110,000 stalks were planted over an area of 6.2 ha. These plantlets were pre-cultivated to a height of about 0.4 m. Dubbe et al. (1988) researched three methods for establishing cattail stands: seeding, transplanting seedlings, and transplanting portions of the rhizome system. The advantages of establishing cattails by transplanting either seedlings or rhizome pieces have a high survival rate resulting in uniform stands and rapid growth during the establishment season. These stands are generally high enough to warrant aboveground biomass harvest in the first year. Unfortunately, transplantation is relatively expensive, slow and labor-intensive (Dubbe et al., 1988). Because of this, according to Dubbe et al. (1988), seeding is the preferred method of stand establishment. Still, this establishment method lacks reliability due to highly variable germination and seedling survival rates, which were tested under different environmental conditions. The system presented by Wild et al. (2000) and Heinz (2011) seems well suited to fulfil the important functional objectives for peatland restoration. First, a water regime typical of fenland was re-established and second, the cattail stands showed a high phytomass production. Consequently the function of the peatland as a sink in the nutrient cycle can be reactivated. 2.3.3. Design of artificial growing bed for Northeast Friesland

Figure 9: A water port connects the water level of two ponds located on the both side of a road. A ditch (not shown in the picture) crosses this port, which was used to adjust the water level of nearby farms. Source: own picture. 13

In Friesland, the flooded areas are separated from each other by farms, roads and terrain. The connection of all the existed ponds and ditches could be complicated. For example, two ponds located on the both sides of a road, are connected by a water port (Figure 9). However, under this port, a ditch was built to adjust the water level of farms in the neighbourhood. To be more specific differences between artificial growing beds for cattail and the current natural growing system can be found in: · Adjustable water levels. The water level in the artificial growing bed should be adjustable or be able to fluctuate naturally. Not only has the water level an influence on the growth of cattail, but it also has an influence on the amount of water which can be stored in a soil. To build a growing bed featuring adjustable water level, a water circulation system and water management tools are necessary. · Access for field management and harvest. The design should leave path for field management, such as maintenance and weeding. What’s more, the access for harvesting machine is also essential, such as the landing shore for conventional harvesting machines or harvesting boats. · Separated blocks (Figure 10). In the natural system cattails are currently only growing on the southwest shore of a lake or a pond because of nutrient transport along with the water flow which accumulates in the south-western corner (Wymenga, 2015). The setting of separated blocks would partially solve the problem. Additionally, block setting also makes the field management easier.

Figure 10: Cattail growing bed design. The size of this growing bed is 1 hectare. The water level is adjusted (max. 80 cm) by pumps, which are located in the diagonal corners of the whole area. The growing bed is connected to ditches/dikes. 1 hectare of growing bed is divided into four separated lanes, each of them is 25 m wide. All the lanes are connected by tubes. Access roads for field management are located between adjacent lanes. An entry or a landing shore for the harvesting boat is fitted on the both sides of these lanes.

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2.3.4. Expected yields The potential productivity of cattail in natural stands and field trials are provided by Dubbe et al., 1988. Mean above- and belowground yields were compiled from reports for stands of the two native cattail species (T. latifolia and T. angustifolia) and their hybrid (T. × glauca). An overview of the yields, presented on a dry weight basis, is provided in Table 4. Strict comparisons of these yields cannot be made since many variables are inherent (Dubbe et al., 1988). Table 4: Comparison of standing crop of cattails, from natural and cultivated stands. Source: Daft et al. (1988) Species Source Standing crop (dry Mg ha-1) Aboveground Belowground Natural stands – North Central USA 4.3-14.8 4.9-9.2 T. latifolia Cultivated stands – Minnesota, USA 4.7-8.2 4.4-5.4 Natural stands – North Central USA 12.3-21.2 -- T. angustifolia Cultivated stands – Minnesota, USA 2.2-13.9 6.6-25.3 Natural stands – North Central USA 6.7-22.4 10.1-30.9 T. × glauca Cultivated stands – Minnesota, USA 5.7-8.1 6.9-9.2

Still, Table 4 indicates that T. angustifolia and T. × glauca are generally more productive than T. latifolia for both the natural stands and the field trials. In field trials designed to compare the yields of cattail species under identical growing conditions (Dubbe et al., 1995), one study found higher yields for T. × glauca (14.8 Mg ha-t of total biomass) than for T. angustifolia (11.7 Mg ha-1 of total biomass). A second trial fround that T. angustifolia produced nearly twice as much shoot biomass (8.1 Mg ha-l) as T. latifolia (4.7 Mg ha-1) under identical field conditions. These two trials agree with data presented in Table 4 which indicate that T. angustifolia and T. × glauca are generally more productive than T. latifolia.

Figure 11: Variation in leaf, rhizome, and total dry weight from pooled data of T. latifolia, T. angustifolia, and T. × glauca over the course of two growing seasons. Sampling intervals equal 28 days. Source: Dubbe et al. (1988) The net seasonal production, defined as “standing crop at the end of the growing season minus standing crop at the beginning of the growing season” (Dubbe et al., 1988), more than doubles for the above-ground biomass in the second year, while net seasonal rhizome biomass production is nearly identical in both years (Figure 11). 15

Figure 11 shows the variations in leaf, rhizome, and total dry weight from cattail over a period of two growing seasons, with the first year being the establishment year. As can be seen in the figure, during the establishment year a peak of dry matter production occurs at twelve weeks, when nearly half of the seasons net biomass production takes place. From this period on the total biomass production continues to increase, although all of this increase occurs in the belowground rhizome system. The general shape of the growth curve in the second season is quite similar. Due to the presence of biomass reserves in the rhizomes at the start of the second year, the period of rapid growth is longer in this season, lasting around eight weeks. Here, approximately two-thirds of the net seasonal biomass is produced (Dubbe et al., 1988).

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3. Harvesting methods For propagation, seeds will be sown in the first year. Once the rhizomes have established, they can reproduce vegetatively in the next growing season. Since our purpose is to increase the water storage capacity, the maximum water level in winter is desired to be 50 centimetres. Within a yearly life cycle of cattail a period of harvest is included. As indicated by Dubbe et al. (1988) it is possible to harvest the leaves and roots of cattail. An annual harvest of cattail leaf biomass combined with a rhizome harvest biennially (50% removal) results in sustainable, but fluctuating, yield which are only 15-20% higher than yields for the annual leaf harvest only scenario. Rhizome harvesting is a significantly more difficult problem than leaf harvesting. Additionally, the loss of soil integrity a companying a rhizome harvest will be higher compared to just a leaf harvest. With a limited demand for the sugar-rich rhizomes, and a biomass productivity of only 15-20% higher than leaf harvest, the rhizome harvest does not appear to be commercially viable when costs of added equipment and operating expense are taken into account needed for rhizome harvest. In addition, experiments of Dubbe et al. (1988) showed that an annual harvest of just leaves results in no stand damage and even appears to enhance productivity by allowing more rapid stand emergence during spring. Hence, when discussing different harvesting methods in this chapter only those harvesting methods were included that are able to harvest the plant just below the water table. Rhizomes are left unharvested and harvesting methods only consider that the stem and leaves are to be harvested. The harvesting frequency and time, without having an impact on the yield of subsequent harvests, is once a year during the end of the growing season (end of July – October) (Toet et al., 2005). Later harvests during winter time result in a lower quality product. The harvesting method should be adjusted to the environmental conditions present at the time of harvest and the size of the harvestable area. To pick the right cattail harvesting method from a farmer’s perspective, a summary of several methods with required machinery, estimated costs, benefits and disadvantages has been made (Table 5). An alternative is to hire a contractor to harvest the fields for farmers to prevent large machinery investment costs and labour time. A third option, if the amount of labour and the required time for that labour is not an issue, there is the possibility of only renting machinery. It should also be kept in mind that a large portion of current farmers in Northeast Friesland are dairy farmers which possibly have no crop harvesting experiences with associated product markets. The first three harvesting methods, listed in Table 5, require a dry or frozen soil for the used (heavy) machinery and can thus only be used during winter. A big disadvantage of this is that chances are that the soil won’t be sufficiently dry nor frozen throughout the harvesting period. Additionally, the machinery causes land and soil damage, which has been reported to be a major harvesting problem by Heinz (2012) when using conventional machinery. They experimented with different cattail harvesting methods (#1, #2 and #3 in Table 5). None of those methods were reliable harvesting methods as they were dependent on the weather and damaging both the land and the plants. Modifying the machinery by applying balloon tires resulted in zero to minimal soil and plant damage, although this modification is only possible with small machinery and thus limits the harvesting speed.

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Table 5: Possible cattail harvesting methods with machinery, costs, benefits and disadvantages of each method. (*)Cost estimates are only of the mentioned machinery, excluding the use of an excavator and transport. Values are based on the accessed websites (Machinery cost) and site numbers match the method numbers. (φ)Slow = longer than 20 h, medium = 2-20 h, quick = less than 2 h. Source: combination of different sources

Method Estimated costs(*) Benefits(φ) Disadvantages(φ) 1. Small machine e.g. Minor plant and soil Slow harvest $1000-3000 Mini Reed Harvester damage Requires frozen soil 2. Crawler walking Requires frozen soil hydraulic drive 4GL-180 $35.000 Medium harvest Medium - major land and reed harvester crop damage 3. Caterpillar drive Major land and crop damage $275.000 Quick harvest heavy machinery Requires frozen soil Medium land and crop 4. Pull-type forage Possible with water damage harvester, modified $40.000 level up to 10 cm Leaves are cut into specific manually Medium harvest size 5. Large aquatic Requires a water level of at harvester (Aquamarine Zero-minor land and least 50 cm H5-200 Aquatic Weed crop damage $50.000 Slow harvest Harvester or Conver Does not require a Large parts get stuck in the MC-105-6/10 mow-cut frozen soil machine and collecting boats) Requires a water level of at least 70 cm Zero-minor land and Material is left in the water 6. Conver C420 mowing crop damage for some time boat + T-front mower + $11.000 Does not require a Collecting of cut material is push rake) frozen soil inefficient Slow – medium speed harvest

Dubbe et al. (1988) also reported the use of a modified conventional machine to circumvent the requirement of a frozen soil for cattail harvesting. They called it an experimental harvester which consisted of a modified flail harvester running in reverse rotation to cut, chop and throw the cattail leaves. This experimental harvester could be used with a water level of up to 10 cm, although it occasionally failed to properly cut the stem and leaves if the soil did not provide sufficient stability for the harvester. Additionally, land and crop damage could not be prevented with the harvester and a yield loss of 2-11% was reported for each harvest. Another approach to prevent land and crop damage while harvesting cattail would be to utilize the water and harvest by boat. This method of harvesting has been used for weed control purposes in lakes in Senegal by Helsten et al. (1999). Cattail is cut just below the water level and will die as a result of anoxic conditions (Sale and Wetzel, 1983; Helsten et al., 1999). Nonetheless, cattail can survive under water for a period of at least a week (Eddy Wymenga). This gives the possibility to harvest cattail below water level to prevent damaging the stalks by boat, followed by lowering of the water level again. The soil water level could also be raised prior to harvesting if taller stalks are desired. It should be kept in mind that this is a crucial part of harvesting by boat, the water level should be adequate to prevent soil and crop damage and to allow for the boat to easily manoeuvre in the water.

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Conver, a Dutch company with dealers in different countries, focuses on creating machinery to efficiently clear lakes of water plants, such as waterpest and reed, as environmental friendly as possible. A specialist of Conver, Hans van den Hurk, discussed two different reed harvesting methods with used machinery which could be used for harvesting cattail. Currently, the first method separates cutting and gathering of the reed. A Conver C420 mowing boat with an attached T-front mower is used to cut the reed (Figure 12). After cutting, the T-front mower is replaced by a push rake to push the cut reed to the side of the water where it is gathered by an excavator and transported away (Figure 12). The mowing width of the T-front mower is 2.0m with a maximum mowing depth of 1.2m. The speed of harvesting is largely determined by the time required for pushing the cut reed to the side of the water as cutting of reed is relatively fast. At least 50 cm of water is required for the boat to easily move around without damaging the boat and soil. The harvesting speed, including cutting, pushing and collecting, was estimated at 1,000 m2·h -1 during the harvesting experiment in the Czech Republic (Figure 12).

Figure 12: Reed harvesting experiment in the Czech Republic using a Conver C420 mowing boat with an attached T-front mower for cutting and a push rake to push the cut reed to the side of the lake (left). The cut reed is then gathered by an excavator and transported (right). Source: Conver (2015).

Figure 13: Harvesting experiment of a reed species using a Conver MC105-10 Weed harvester with a U-front mower for cutting and a porous conveyor belt to transport the cut material onto the harvester’s storage unit of 17.5m3 (left). Harvested material is released by reverse rotation of the belt (right). Source: Conver (2015).

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The second method of harvesting combines cutting and gathering of the reed by use of a Conver MC105-10 Weed harvester (Figure 13). This harvesting boat is generally used to harvest weeds and is equipped with a U-front mower to cut water plants. At least 70 cm of water is required for the boat to easily move around without damaging the boat and soil. The advantage of this harvester is that it uses a porous conveyor belt to transport the cut-off material onto the harvester and is consequently stored in a 17,5m3 container unit (Figure 13). A disadvantage of the harvester is that cattail is not easily compressed and is inefficiently stored in the container. Additionally, the stored plant material is released through the same way that it got into the harvester. In other words, entrance and exit as the same. This may form a problem for cattail when its long plant material is released, and for example the stems and leaves get stuck along the trajectory. Due to mentioned practical constraints this harvesting method is less efficient than the first and requires modification before it is practically interesting.

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4. Production and processing of bio-laminate and insulating material Research on current applications of cattail shows that cattail can be used in a wide range of sectors (ACT project, 2013). Current applications of cattail are found in sectors like the food industry, waste water treatment by means of phytoremediation, and the medicine and cosmetics industry. In addition, one of these applications has been illustrated in section XXX: the contribution of cattail on the restoration of wetlands. Still, more research is needed to identify other applications of cattail. In this chapter two relatively new potential applications of cattail are illustrated, where cattail is used for the production of the high-valued products of insulating material and bio-laminate. The shoots and leaves of cattail are rich in aerenchyma tissue which makes cattail excellent for the use as insulating material or as an alternative to wood fibre in the production of bio-laminate (Pfadenfauer & Grootjans, 1999). 4.1. Using cattail for Bio-laminate Over the last years, an interest in using the green fibres of cattail has increased in sectors like the automobile and furniture industry (ACT project, 2013). This is due to the remarkable self-gluing properties of the cattail fibre composites. These composite fibres can be prepared without any addition of a binder system due to natural constituents of cattail that act as an intrinsic binder. The use of the fibres has increased due to their relative cheapness, their ability to be recycled and due to their strength per weight of material. In addition, the cattail composites represent an alternative material to wood fibre because of their lower reproduction cycle and favourable surface roughness. These finding provides great opportunities for the use of cattail fibres in the production of bio- laminate. Bio-laminates are made from materials that are considered waste or have no apparent function (HuisVeendam, 2014). The waste material is converted into a product which is biodegradable. The production procedure requires a low amount of water, which will not be contaminated, and energy. Harmful substances are not released during or after the production process. These implications make bio-laminates sustainable products. At this moment not much literature is available about the application of cattail in bio-laminates. To get more into detail about the production process Triple C got in touch with Tjeerd Veenhoven, initiator of HuisVeendam, who has experiences in using cattail to create bio-laminates applicable on walls, objects and in the future also flooring (HuisVeendam, 2013). As can be seen in Figure 16 different parts of cattail can be used for the top layer of bio-laminates. Only the lowest part of the shoots (below the water table) and the roots are not of interest. The cattail used for this project was harvested, just below the water level, in a pilot area in Friesland where cattail is currently growing. Afterward, the material had to be dried for several weeks (e.g 3 – 4 weeks), to prevent future shrinkage and expanding of the final end product. By means of organic glue, called potato starch biopolymer, the various particulars of the fibres are accommodated. After the binding procedure, the cattail is pressed into the desired thickness needed for the material to function as a top-layer of bio-laminate of approximately 3 mm. Experiences gained in creating these bio-laminates showed that T. angustifolia is most suitable for the production process. This is due to the smaller leaves of T. angustifolia compared to T. latifolia, which requires less time and money to be broken down. Assuming a two year old cultivated stand 21 of T. angustifolia as typical for the region would result in a possible harvest of total above ground dry biomass of 10 Mgr / ha or 1 kg / m2 (Pratt et al., 1988). We estimate that the bottom 50 cm of a 1 m2 patch contains around 30% of its total biomass (Pratt et al., 1988), which would make the harvestable amount 0.7 kg / m2. Secondly, we estimate the biomass to have an average weight of 0.25 kg / dm3 or 250 kg / m3. Currently the yearly demand for T. angustifolia is not greater than 150 m3 (Veenhoven, 2015), which would require a surface area of 6 ha. The Actueel Hoogtebestand Nederland, used in Arcmap, has a resolution of 5 m, 25 m2 per cell, and 6 ha would amount to 2400 cells. As can be seen in Figure 7 and Table 2 (see chapter 2.2.2) a large enough area, at the required elevation of 200 cm below NAP, is present in the Veenwoude area. Although the market is excited about this innovative process, the current market for these bio- laminates is still rather small. That is why Tjeerd Veenhoven suggested to start the cultivation of cattail in Northeast Friesland on a small sale. Cultivating cattail on a small scale will not solve the problem of increasing the water storage capacity up to amounts that pumping is no longer necessary in Friesland. Still, spatial complication when constructing a wetland (e.g. conflicts of landownership or restricted availability of land) are somewhat limited. This increases the chance of restoration projects as such conflicts are the main reason why many restoration projects fail (Pfadenhauer & Grootjans, 1999). 4.2. Using cattail for insulation material Nowadays, insulation material for home applications is commonly used for energy conservation. The heating system has become an essential part of modern buildings. In addition, energy loss is an increasing problem for human beings. Saving energy in accommodations and buildings is more interesting now than it has been in the past. One effective way of saving energy in accommodations and buildings is by applying a form of insulation material due to the ability to reduce the heat conduction rate. Insulating material is used all around the world and can be made in many different forms. In the past, most insulating material was inorganic, such as glass fibre. However, working with fibre glass poses health risks to the workers (Luamkanchanaphan et al., 2012; Block, 1992). Nowadays, much research has been done to find alternative ways to produce insulating material from a natural fibre source, like eggplant stalks (Guntekin and Karakus, 2008) and sun flower stalks (Binici et al., 2014). Among natural fibre sources, cattail is a relatively new insulating material and stands out because of its tremendous environment adapting capability and the enormous yield. Furthermore, the tear and break resistant structure and flexible characteristics of cattail leaves are suitable for insulating material (Krus et al., 2014). Compared to traditional inorganic insulating material, the cattail insulating material production process is relatively simple and environment friendly. 4.2.1. Products Insulation material products are mainly designed to conserve energy combined with a limited fireproof capability. The main idea of insulation material is to slow down the transport of heat within a building (in and out). This means that the insulation material should have a high thermal resistance and a low thermal conductivity (Al-Homoud, 2005). The capability of a heat insulating material is not only defined by these properties, but also by its density and thickness. The density ranges from 200 to 400 kg/m3 and the thermal conductivity varies between the 0.0438-0.0606

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W/mK. Hence, the capacity of cattail insulation material stands out when it is compared to a range of other organic insulation material, like cotton stalk fiber, which has a thermal conductivity varying between the 0.0585-0.0815 W/mK., and wheat straw board, thermal conductivity ranges between 0.0585-0.0815 W/mK (Zhou et al., 2010). Cattail insulation material is generally distinguished in two formations: 1) insulation board and 2) insulation block. Insulation boards of different sizes can be used for different applications, like a wall or furniture. The insulation blocks are mainly used as construction material in architecture. 4.2.2. Production Procedure Cattail Insulation Board The building procedure contains two major steps: first the raw material needs preparation. The second step is processing the insulation board. The methods and procedures are based on the instruction of Luamkanchanaphan et al. (2012) and Maddison et al. (2010). In Figure 14 provides an overview of the production process of the insulation boards. The raw material from the (narrow) leaves of T. agustifolia were dried under 70 °C. Afterwards, the dried leaves were cut into a fixed length (i.e. 10 centimetres). Next, the leaves are fiberized, with the use of wood grinder, which makes the raw material ready for subsequent processing. With a different demand for products, the weight of raw material varies also. Methylene Diphenyl Diisocyanate (MDI), as a binder of fibre, is sprayed and mixed with prepared raw material. The mixture is shaped in a forming box, which is applicable for heat pressing machine. After forming, the heat pressing is applied with the pressure of 40 kg/cm2, under 140 °C for 3 min. The shaped mixture was pressed into the target thickness. When the heat processing step is finished, the board is stored in a conditioning room for one week. Then the board with target thickness is cut into target product size and finish the process with polish or other works for the demand of final products.

Figure 14: The production process of cattail-based insulation material. A-B: Cattail raw material is harvested and dried under 70℃ to a constant weight. B-C: Cattail leaves are cut off and collected. C-D: Cattail leaves are all sliced into a constant length (i.e. 10 cm). D-E: The sliced leaf pieces are grinded and fiberized through a wood grinder and then mixed with MDI. E-F: The mixture is shaped in a forming box and then compressed by a heat pressing machine (40 kg/cm2, 140℃ for 3 min). F-G: After heat pressing, the boards are stored in conditioning room for a week. Source: own design. 23

The binding glue or adhesive is the sole ingredient to raw material, which makes the permanent binding of the adhesive particles to building materials. Some researchers found that the adhesive could definitely enhance the strength of products and achieve permanent binding. However, according to their research, the adhesive is not suitable for the products to return to material recycling. Besides, the synthetic adhesives are usually quite expensive (Theuerkorn et al., 2013). Mineral binders, on the other hand, are very cheap, such as cement. However, the adhesive capability of cement is quite weak comparing to synthetic adhesive. The thermal resistance of insulation board is mainly due to the air space between material particles. Theuerkorn et al. used magnesite as binder to create cattail based insulation material. Their products are totally compostable and featuring a good insulating capability. The density of material and the dosage of magnesite effect the insulating capability of the final products. They tested the material in density ranging from 217 kg/m3 to 346 kg/m3 with 40% to 60% of magnesite binding. The thermal conductivity of their products is ranges from 0.048 to 0.061 W/Km (Theuerkorn et al., 2013). With that, the magnesite binding insulation material is quite equal to the insulating capability of MDI binding insulation material. Magnesite binding insulation material is also mould growth-resistant and sound proofing (Krus et al., 2014). Cattail Insulation Block The main procedures of cattail based insulation blacks are mixing the raw material of cattail with clay and fibre-wool (Figure 15). The composition of the clay that Maddison et al. (2009) used in their research mainly consist of quartz (54.7%), dolomite (13.1%) and calcite (12.1%).The raw material includes all of the aboveground parts of cattail. To process the harvested raw material, cattail shoots and leaves were sliced into 2×20 mm chips. In addition, as an additive substance, the seeds from cattail inflorescence were made into cattail fibre-wool. The sliced cattail shoots and leaves were mixed with clay material and cattail fibre wool. Fibre mixed with raw material and clay-sand could reinforce the block and decrease moisture absorption. At last, the mixture was shaped into cubes and then the products were ready for sale (Maddison et al., 2009).

Figure 15: Use of cattail as raw material: A) Cattail fiber wool made from cattail inflorescence after initial treatment, and B) cattail based insulation blocks combined with clay material (Theuerkorn et al., 2013).

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5. Market Identification The implementation of cattail cultivation is demanded to comply two purposes. Firstly, it shall increase the water storage capacities to face the water problems of Northeast Friesland by inundating adequate areas. Secondly, as this purpose is in objection to the current agricultural business (see chapter 6), cattail cultivation should create a new income source for compensation of the farmers that are going to lose their arable land by the means of flooding. In order to meet this purpose a production chain of cattail cultivation is required with valuable and profitable products at its end. For this reason, Triple C by advice of Wymenga (2015) focuses on isolating material and bio- laminate as target products as they are expected to be the most valuable products made from cattail. The following chapters contain information about the investigation of the current markets of insulating material and bio-laminate. Next, the valuable characteristics of cattail on these markets are summed up and recommendations are given. At this point it has to be said, that for Triple C it was hard to find information on these markets. Investigations showed that meaningful market data are to a high degree sensible and not available without charge. As investments into such available data would widely exceed the determined budget of this research project, Triple C contacted established market data bases for individual access to information. Yet, by referring to the high expenditures of their market analysis, the desired access was denied. Only buildsight.nl was willing to give a small insight into data available for natural insulating materials. As a result, Triple C had to base their investigation of the market conditions on rare available information mainly from secondary sources like information bases for private customers. For bio-laminate information the problem of finding information was even worse since less information was available. 5.1. Insulating Material The range of insulating material is huge and difficult to classify, as there are several varieties of used materials and fields of application (e.g. thermal- or sound insulation). Those materials differ in characteristics like insulating factors, fire protection, noise protection, elasticity or hydrophobicity (Sprengard et al., 2014). The range of requirements for insulating applications is wide and of less importance for the purpose of this project. According to isolatie-weetjes.nl (2015) there are three different sources for insulating materials. The most usual ones are either mineral or synthetic materials. Well known and commonly used mineral materials are laggings from glass wool or rock wool. For example glass wool, processed from recycled glass and grit, is appreciated due to its high isolating capacity and its sound protection provided by its aerial structure (isolatie-weetjes.nl, 2015). However, working with glass wool is not comfortable as its fibres are skin irritating and unhealthy (houhetwarm.nl, 2015) Synthetic insulating materials are chemical combinations like Polyurethane (PUR) or Polyisocyanurate (PIR), which are very light weighted materials but though having a high insulating value. This makes them very easy to work with. Moreover, synthetic materials are often water-repellent which widens the potential application. The disadvantage of synthetic is its use and dependency on chemical substances (isolatie-weetjes.nl, 2015.).

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The last kind of differentiation between isolating materials are those based on natural sources characterized by environmental friendliness and sustainability in growing and processing. Examples of natural insulating materials are cork or cellulose or fibres from wood or hemp (isolatie-weetjes.nl, 2015). Cellulose isolation for example, based on recycling of old paper, is with its insulating factor comparable to other materials and especially advantageous for application in cavities. Insulating materials from cork, having an adequate insulating factor also allow, besides the use as fill material, other applications like wall or roof isolating since it can be processed into insulating plates (isolatie-weetjes.nl, 2015). Since cattail is a natural, perennial plant, laggings based on this plant would also belong to the natural insulating materials. The question arises whether cattail can meet the characteristics required in the insulating market. Therefore chapter 5.1.4 gives an impression of the opportunities of cattail for this purpose. 5.1.1. Market Volume For a better overview of the insulating material situation in The Netherlands it is important to have an impression of the market volume. Therefore Table 6 shows the sales quantity of synthetic and mineral insulating materials of the years 2010 until 2012 as those materials are the most commonly used. It thereby distinguishes between the application in new and in existing constructions. However, it does not include data on insulating material made from natural sources. Table 6 shows through the years that with a share around 53 % and an amount of about 39 mln. m² the most used isolating material is made from mineral sources like rock wool or glass wool. Moreover, mineral materials are used more or less in similar amounts either for new buildings or in existing constructions. Table 6: Sales Quantities of most used insulating materials (2010-2012). Source: Agentschap NL (2014) Tendency (of 2012 in Insulating material (in mln. m²) 2010 2011 2012 relation to previous year) Sum of mineral and synthetic material 37.7 40.2 38.2 -5% total 20.8 21.6 19.8 -8.4 share 55.2% 53.7 51.8% new construction 10.6 10.3 9.3 Mineral -9.7 share 28.1% 25.6% 24.3% existing construction 10.1 11.4 10.5 -7.8 share 26.8% 28.3% 27.5 total 16.9 18.6 18.4 -1 share 44.8% 46.3% 48.2% new construction 11.5 11.3 13.3 Synthetic +1.8 share 30.5% 28.1% 34.8% existing construction 5.4 7,3 5.1 -30 share 14.3% 18.6% 13.3%

When it comes to synthetic materials, their shares on total sales are around 46.5 % and hence lower than mineral insulating materials. However, within this segment it is more often used for new constructions than for existing buildings. Comparing the areas of application, synthetic laggings

26 play a bigger role in new constructions whereas mineral insulating materials are used nearly twice as much than synthetic materials in existing constructions. Concerning the movement in sales volume, the total market has increased from 2010 to 2011. Although both material sources gained from higher demands within this period, synthetic insulating laggings made bigger steps as they increased sales around 2 mln. m² whereas mineral materials increased by nearly 1 mln m². It is remarkable that this movement took place only in the segment of existing constructions, as the sales meant for application in new constructions stayed rather similar or even decreased. The whole increase of synthetic insulation material for example is caused by higher sales for existing constructions. According to Agentschap NL (2014) the market benefited by the stimulation measures from the government that were introduced to support a more climate aware and energy saving way of construction especially in the existing buildings. Moreover, the construction sector as a whole may have benefited from the reduction of turnover tax for working hours (ZZP Nederland, 2010) as it stimulates the willingness to invest in to buildings by lower costs for work. That such support measures indeed influenced the market can be seen in the movement from 2011 to 2012 when measures like reduced turnover taxes where retired. Besides a small increase of insulating sales for new constructions, nearly all segments of the market dropped sales compared to the previous year by about 5-10 %. The biggest decrease was observed at synthetic insulating materials for existing constructions as they even lost about 30% in sales. Above mentioned quantitative data do not include natural insulating materials. According to Dankers (2015) a market analyst at the database buildsight.nl, the share of natural insulating materials in The Netherlands is small compared to the total market. Yet, Triple C is not allowed by buildsight.nl to publish the size of natural lagging sales as these data are highly sensitive. Following Duurzaam Thuis (2015) the sales of such material are just small shares compared to the quantities of other countries. For comparison, in the year 1997 in Germany the share of insulating material processed from natural resources was about 5% of their total market size. According to Sprengard et al. (2014) the share remained at this level and an expected increase to 9-13% was not observable. In the year 2010, the market of insulating material in Germany had a size of about 28 mln. m³ (other dimension!) (Sprengard et al., 2014, p.73) which means 1.4 mln. m³ of sales volume for natural insulating materials when assuming this 5 % market share. Whether the level of 5 % also is reached in The Netherlands remains unanswered. However, there is market for natural lagging materials although with a limited interest. Chapter 5.1.3 gives an impression of why natural insulating materials are of lower importance. 5.1.2. Price Comparison Insulating materials also differ regarding their prices. Table 7 shows for some insulating materials the average customer purchasing price.

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Table 7: Consumer prices for different insulating materials. (Source: isolatie-weetjes.nl).

Kind of material Price (€/m²) synthetic PUR 25 PIR 12 mineral Rock wool 8 Glass wool 7.5 Cellulose 13 natural Wood fibres 20 Cork 30 The Table 7 gives a price impression of several kinds of laggings. Of course, no direct conclusion can be made from this because they will differ in their characteristics. Nevertheless, it can be recognized that within the field of natural insulating materials there are high price differences. Additionally, the table shows that mineral insulating materials are lower priced than synthetic materials which will probably be one of the main reasons why they are more used than other materials (Table 6). 5.1.3. Reasons for Minor Market Importance of Insulating Materials There are three main aspects why natural insulating materials play a less important role in Dutch markets. The first concerns the market as such. The second is based on the typical Dutch construction system and the third reason lies in the regulation system of construction material. At first, the demand for sustainable innovations has not really evolved yet as the market has a rather conventional attitude (Vellema, 2003). In addition, the higher price of natural laggings due to higher labour expenses (see Table 7) causes reluctance in applying. Comparable insulating performances of natural materials to usual laggings are no sufficient reasons to accept higher prices. If no additional value of those insulating materials can be promoted, they are simply not competitive and therefore of minor interest (Vellema, 2003). Another reason for the low share of insulating material can be found in the usual Dutch way of massive construction. Few buildings were constructed on initiative of private persons but most were arranged in big projects. Dutch houses were then build in series production in which questions to used materials fall to the architect in charge and hence were not concerned by the customer. As long as a less sustainable thinking architect is responsible for such projects, standard materials will be used and innovative and sustainable solutions are neglected (Duurzaam Thuis, 2015). The last reason exist is due to the complex regulation system. As the certification procedure of laggings is adjusted to the commonly used materials, there is less room for new, in particular natural insulating materials which complicates their development (Vellema, 2003). 5.1.4. Assessment of cattail as source for insulating materials Using cattail for the processing of insulating materials has good strengths. Cattail-based insulation material has the excellent capability of heat insulating comparing to traditional insulation material, for example glass fibre (Theuerkorn et al., 2013). Even comparing to other plant-based insulation material, like cotton stalk fibre (Zhou et al., 2010), it is still a promising products. Additionally, the production procedure is easier, more environmental friendly and much less harmful than glass fibre production (Luamkanchanaphan et al., 2012). What’s more, cattail based insulation material also 28 have the property of water-proof (Maddison et al., 2009), sound-proof and mould growth resistance (Krus et al., 2014), which make the cattail based material a perfect product for building and furniture. 5.1.5. Recommendations cattail as insulating material Having all information from above in mind it comes to the question whether cattail is suitable as raw material for the market in terms of insulating characteristics and in terms of competitiveness. In the following section some approximate and intuitive recommendations for the opportunities of cattail-laggings are given. As stated above cattail is in its insulating effects comparable to others and thereby has the opportunity to replace traditional players on the market. Yet, the usual materials will be lower priced and therefore cattail insulations cannot be marketed as low-cost product with having the opportunity to fully replace important competitive laggings like mineral insulating materials. For this reason, cattail insulation has to deliver additional value which has to be marketed in order to compensate a higher price. Therefore it is beneficial, that those additional values like the water- proofed characteristic or the resistance against mould growth exist. Since the market of insulating materials is huge, this gives plenty of opportunities for cattail products to be placed. It should be investigated in which field of applications cattail based materials can be placed at such competitive prices that are reasonable for both, production costs and market substitutes. Since cattail insulating materials are at the moment in the research phase they are not yet ready for the market. Due to this reason it is too early to give a significant recommendation on the placing of the laggings in the market. Further investigations are therefore needed. Concerning the second obstacle of natural insulating materials, it is important that the sustainable production and the ecological efficiency of cattail as material is promoted and that construction companies, architects and in the end customers become aware that cattail laggings are not necessary ranked behind common insulating materials but that they can be seen as ecologically worthwhile alternatives. In addition, Table 6 concludes that the segment of applying insulating material in existing buildings has a big share in the total market. Furthermore, it shows the reaction of the market on governmental incentive measures for a more energy-efficient construction as the sales quantity increased from 2010 to 2011. A positioning of cattail laggings may benefit from this interdependence when cattail´s connection between insulating characteristics and sustainability can be promoted. Therefore the aspects of sustainability and ecological efficiency should be introduced on governmental level in order to aim for their support. To summarize, the idea of taking insulating materials as target products from cattail is a reasonable and auspicious choice for the goal of increasing water storage capacity and creating value for farmers´ flooded land. The insulating market is a lucrative market to offset the biomass produced as through its size also high sales quantities resulting in high demand for cattail raw material are potentially possible. This assumed high demand for raw materials would not only include positive effects on the selling price for farmers, but also means that the cultivation at a certain moment needs to be expanded. An expansion of cattail growing areas in turn would increase the water storage capacity in Northeast Friesland. That cattail insulations can be successfully marketed seems likely as cattail-based products are concerning their characteristics comparable. However, they will 29 face strong competitors who only can be beaten if additional benefit can be promoted. Significant research is therefore needed to investigate how and where the advantages, including its attribute of being a natural source for materials, should be placed on the market. 5.2. Bio-laminate As it is mentioned before, Triple C was hardly able to find market information for the flooring market in The Netherlands. By asking several producers or associations of manufacturers and market analysis organizations, it turned out that their information on the flooring market is confidential. Because of the close distance to the customer and the huge competition in the market, none of the asked instances was willing to give a useful insight into the market without purchasing the market analysis. 5.2.1. Market situation However, there are some data available for the total sales quantity of laminate floorings. Figure 16 shows the sales of Western Europe.

Figure 15: Sales quantities of laminate floorings in Western Europe (mln.m²). Source: EPLF, (a) The graph shows that the importance of Dutch laminate flooring sales compared to other Western European Countries is rather low. Germany´s market is one of the biggest with a quantity of 72 mln. m² and therewith nearly four times bigger than the sales market in The Netherlands. Table 8 shows the history of total sales quantity of laminate floorings in The Netherlands. It can be seen that the sales from the years 2008 until 2011 stayed constant, whereas the years 2012 and 2013 faced decreases in sales of about 12 % compared to the years before.

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Table 8: Sales of laminate floorings in The Netherlands (2008-2013). (Source: Data from EPLF, (b)

Year Laminate sales (in mln. m²) 2008 22 2009 21.5 2010 21 2011 21 2012 18.5 2013 19

Unfortunately, these data are not meaningful enough to draw any conclusions from it. Moreover, no additional information is available for Triple C on whether and which different kinds of materials are used. Through this, no drawbacks on opportunities for cattail based floorings can be made. However, the available data indeed shows that the market of laminate flooring has a meaningful size and even better that the Netherlands is located in the neighbourhood of the biggest European sales market. At least it can be said that if a successful product based on cattail can be developed those big markets can facilitate the marketing opportunities. 5.2.2. Cattail based floorings First considerations planned cattail to be used as substitute for the base layer of laminate floorings. In the current situation the base layer “is from high-density wood fiber boards (HDF) (…) [covered by] high-quality paper (…)” on top (Marutzky, 2007). Those base layers are according to Veenhoven (2015) by far lower priced than cattail based layers would be. Moreover, since wood sources are already renewable materials, cattail cannot perform this aspect as additional value. By this, the opportunity of using cattail to replace wooded base layers is neither cost-efficient nor can be promoted as more ecological worthwhile. Hence, the idea of cattail as base layer has to be abandoned. This is a disappointment, because when cattail would be competitive to wooded layers, this could have raised huge demands according to the national and international size of the laminate market. Although the initial determination of the application of cattail seemed not suitable, there is another possibility to use the plant in this field. Veenhoven (2015) recommended using cattail as a top layer of laminate floorings. By compressing the plant to a thickness of 3 mm, this process results into a nice design layer with natural look of cattail plants (see Figure 16).

Figure 16: examples of floorings with cattail design, top view and side view, own pictures 31

Focusing on the idea of using cattail as design layer, the following model calculation can be made on the base of Veenhoven ´s information. According to him, he is willing to pay 75 €/t dry matter from the farmer. By processing plates with cattail as a decoration layer Veenhoven expects 10 €/m² including energy in costs and materials, but excluding the relatively expensive wooden base layer. The cattail is delivered workshop for processing so that the transportation costs, expected to be 10 €/t, are covered by the farmer. Table 9: Model calculation of processing plates with cattail as top layer. Source: Information from Veenhoven (2015).

revenue price of cattail designing plate 120 €/m² costs processing costs (excluding wood layer) 10 €/m² profit processing margin 110 €/m²

According to the information from Veenhoven such plates then can be sold for 120 €/m² which would result into a processing margin of 110 €/m² excluding the costs for the wooded base layer (Table 9). Although there is a lucrative processing margin, this value creation cannot be translated to general situations or applications since it refers to the conditions of Veenhoven. Moreover, this application would be limited to the actual production capacity of his plant. Still, it gives an impression of what might be possible for cattail as design layer. Another advantage of this cattail design is that it is not limited to the field of laminate floorings. Instead, this idea can be easily transferred to other markets that are confronted with a demand on design. This idea thereby focuses on such customers that are looking for alternatively looking designs. According to Veenhoven one of such application fields could be dashboards of cars. He already uses this top layer design idea with different kind of materials successfully for furniture. 5.2.3. Recommendations cattail in laminate floorings The initial idea of using cattail as base layer in laminate floorings turned out as not cost-efficient compared to the already used materials for this. Hence, this possibility has to be abandoned. Another idea developed by Veenhoven contents to use cattail as design layer for laminate. Based on his information, the model calculation showed that such application of cattail is a very lucrative opportunity since high margins can be obtained. However, it is restricted since the design layer made from cattail is very different to usual appearances of laminate top layers. Assuming that only a small share of laminate customers having interest into such alternative designs, this implies that the potential market of cattail laminate floorings is limited. This in turn means that bigger sized cultivation areas only based on the production of laminate as target product likely is not possible since the demand for its raw material will be limited. Although this concept of using cattail as top layer can be transferred into other markets increasing the cattail demand, it remains unlikely this production purpose is capable to implement cattail cultivations. However, for starting up researches on cattail growing this application is easily developed as well as implemented and the limited capacity of Veenhoven ´s production would not be a problem for economizing the raw materials of a potential sample area.

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6. Impact of cattail cultivation on agriculture situation Flooding of agricultural land in Friesland is an approach to increase the water storage capacity, although this will provoke resistance of farmers who don’t want their land to be inundated. As the farmers are dependent on the income of their land, they fear for losses of land value. Therefore, it is required to provide profitable alternatives in order to convince them of flooding their lands. Growing cattail is seen as a lucrative opportunity to retain the worthiness of the land as it has characteristics that may make it worthwhile. Some opportunities to economize products from cattail can be found in chapter 5 and at this point the question arises whether or not the implementation of a cattail production chain would also be lucrative for farmers. In order to get an impression of the impact of setting up a cattail cultivation chain on the agricultural sector of Northeast Friesland, the following section first gives an overview of the current farming situation in this area. It thereby explores the most important form of agriculture and identifies reference values of how the actual cultivated land is evaluated by the farming sector. In a next step the economic impact of raising water levels for the farming sector is explained. Afterwards, a theoretical model of farming under flooded conditions by using cattail will be introduced. Finally, it will be assessed whether this situation will be of interest for farmers. 6.1. Actual farming situation in Northeast Friesland In the whole province of Friesland there is about 237,000 ha of land in use divided amongst nearly 6000 farmers. 66% of this arable area is property of the farmers (Venema et al., 2009) and 80% of the total agricultural land is used as grassland (Venema et al., 2009). The 6000 farms located in Friesland have a share of 8% of all farms in The Netherlands and even contribute as 44% to the total number of farms in the north of The Netherlands (Venema et al., 2009). Half of these 6000 farms are specialized dairy farms and contribute to nearly 17% of the Dutch dairy farms. Besides 400 arable farms, the rest of the farms are animal farms combined with grassland (Venema et al., 2009). With a focus on the 3000 specialized dairy farms, 265,000 cows are kept on these farms which corresponds to 20% of all Dutch dairy cattle. On average, each of those farms uses 50ha land (Venema et al., 2009). Dairy farms are the most important forms of agriculture in Friesland and specialize in producing conventional milk, which means that they depend on their grassland. To give an indication of the average income by specialized milk production per farm is about 100,000€/a (Venema et al., 2009). 6.1.1. Actual farming situation in Northeast Friesland In the whole province of Friesland there is about 237,000 ha of land in use divided amongst nearly 6000 farmers. 66% of this arable area is property of the farmers (Venema et al., 2009) and 80% of the total agricultural land is used as grassland (Venema et al., 2009). The 6000 farms located in Friesland have a share of 8% of all farms in The Netherlands and even contribute as 44% to the total number of farms in the north of The Netherlands (Venema et al., 2009). Half of these 6000 farms are specialized dairy farms and contribute to nearly 17% of the Dutch dairy farms. Besides 400 arable farms, the rest of the farms are animal farms combined with grassland (Venema et al., 2009). With a focus on the 3000 specialized dairy farms, 265,000 cows are kept on these farms which corresponds to 20% of all Dutch dairy cattle. On average, each of

33 those farms uses 50ha land (Venema et al., 2009). Dairy farms are the most important forms of agriculture in Friesland and specialize in producing conventional milk, which means that they depend on their grassland. To give an indication of the average income by specialized milk production per farm is about 100,000€/a (Venema et al., 2009). 6.1.2. Introducing cattail as growing alternative As indicated, the idea of introducing cattail as a crop for farmers was two-folded. At first it should be a support in solving the water-problems of Northeast Friesland by growing on flooded areas. Secondly, important in this part, it should provide value for flooded areas by delivering valuable raw material for further production. At a certain moment the profit from grassland is thus low that it becomes interesting to flood and make a transition to other forms of cultivation, at which cattail could be a profitable one. In order to propose cattail as alternative crop it is important that it can deliver a reasonable margin for the farmers. To get an indication on whether there is a margin for cattail cultivation, the following part introduces the model calculation with its underlying assumptions and data. After the outcome of the calculation the expected value for the margin per ha for cattail cultivation will be compared to the two situations introduced in chapter 2.2. As a final step, recommendations on the feasibility of cattail cultivation under those assumptions are given. 6.2. Model calculation cattail cultivation The question arises whether cattail cultivation can be seen as a lucrative alternative to existing farming for those fields that are going to be flooded. The difficulty at this moment is that there is no cattail cultivation under Dutch conditions and hence no real existing data. However, Triple C will generate a model calculation of cattail cultivation based on the findings of the previous topics. In the following all relevant items of the model calculation will be explained. Yield: Referring to chapter 4.1 the yield of cattail growing is expected to be 10 Mgr / ha and that equals to 10 t/ha. Producer price: For this model Triple C assumes that cattail is going to be used as raw material for the purpose of making design layers of it (see chapter…). In this context, Veenhoven was willing to pay 75 €/t of dry matter cattail. He would like to receive it as dry as possible, but he will carry additional required drying. Seed costs: In order to have a sufficient amount of raw material, an amount of 250,000 plants per hectare is needed. Growing 1,000 plants of T. angustifolia requires 0.5 gram seeds which equals to 125 grams per hectare. According to the price given by Jelitto it costs 3.2 €/gram when buying over 100 gram seeds. Therefore, the cost of T. angustifolia seeds will be 400 €/ha. Yet, current cultivating experience showed that once sowed the T. angustifolia can spread by vegetative reproduction for around six years. After that the yield will be decrease and another sowing is needed (Pratt et al., 1988). Accordingly the price of the seeds will be paid only each 6 years. Hence, yearly cost for the seeds is calculated to 67 €/ha. Investment costs: Triple C assumes that there are no big investments necessary. Of course, the generation of growing beds is connected to expenditures but at this moment neglected. Fertilization measures: They are not necessary in cattail cultivation and therefore not considered. 34

Harvesting: In a study in Switzerland on cultivating cattail a machine similar to a self-pulled forage harvester was used to harvest the cattail (Rohrkolben.ch, 2015). Triple C estimates harvesting performance of cattail with this type of machinery around 1 ha/h. The costs of renting such a machine with header are estimated at $316 per hour (Government of Saskatchewan, 2014). This equals to €281 renting cost per hour for harvesting of the cattail and includes ownership cost, repair & maintenance cost, margins for the farmer as well as fuel and labor costs. For transportation of the harvested cattail to the desired location an additional €10 per ton (Veenhoven, 2015) of material is taken into account. One hectare of cattail yields about 10 t of material, so this would result in an additional €100 cost for transportation of the harvested material. In total this sums up to a cost of roughly €400 for harvesting one hectare of cattail, excluding any other costs made such as driving the vehicle to its destination point. Another method of harvesting is by utilizing water. The current boats however are not designed for cattail harvesting purposes. Therefore the harvesting of cattail takes too long compared to harvesting with conventional machinery which raises costs. For example harvesting with a Conver 420 mowing boat takes around 10 hours with an estimated cost of €60-70 per hour with an additional €50 fuel cost (Conver, 2015). Taking into account that harvesting by boat will become cheaper in the future once the boats are adapted to the purpose, further calculations are based on the above explained cost of €400 for harvesting a hectare of cattail. Labour costs: At the moment there is no real estimation of labour costs available. Therefore Triple C assumes for cattail cultivation costs of 200 €/ha for seeding and other work like plant protection measures. Additional costs: Costs that are connected to the cultivation but not distributable. At this point they were not considered. In the following Table 10 all above explained items are used to calculate the profit per ha. Table 10: Model calculation of cattail cultivation. Source: own calculation. producer price €/t 75 expected yield t/ha DM 10 revenue €/ha 750 Seeding costs €/ha 67 costs Labour costs €/ha 200 Harvesting costs €/ha 400 Total costs €/ha 667 profit margin €/ha 83

Following the above explained data cattail cultivation for the farmers causes total expenditures of €667 and revenue of €750 resulting in profit of 83 €/ha. Although the assumptions made have to be examined which might change the result, this calculation shows that cultivating cattail delivers a positive result. This finding is important for the initial purpose to find value creating alternatives for the farming sector. As it is a first impression of the feasibility of cultivation in the Netherlands it shows that it is profitable, although the profit is very low. Comparing the profit of 83 €/ha with the optimal situation of growing grass in Northeast Friesland which earns 800 €/ha it becomes clear that it is much more profitable for the farmer to keep his existing farming business running. Moreover, the lower profit consequently implies that for 35 reaching the average income of a dairy farmer of 100,000 €/year (see chapter 6.1), much more area has to be cultivated with cattail. Yet, investments into land for cattail production would not be compensated by its profit and on top of that the availability of arable land of farmers is restricted. Conclusively, a farmer is not willing to invest into cattail cultivation based on economic considerations. However, the conditions may change and farmers are forced to work with higher water levels. This would be the case if the government decides to increase the water level or even forces the flooding some areas in order to increase the water storage capacity. In this case farmers will have to work under wet conditions and the reference value of -500 €/ha of farming under wet conditions (chapter 6.1.1) applies. Farmers that are facing too wet conditions for their grassland will then, on economic grounds, appreciate the possibility of growing cattail as alternative. Comparing the loss of 500 €/ha to the profit of 83 €/ha this will either result in a change of farming system towards the cultivation of cattail if that is the only alternative crop or the cessation of farming altogether. To summarize, cattail cultivation is able to bear its costs and even provides a small profit of 83 €/ha. However, under the current dry conditions, cattail cultivation cannot compete with the current way of farming in Northeast Friesland since grassland is more profitable with 800 €/ha. Yet, if other conditions apply so that farmers have to cultivate under wet conditions, for example due to an increase of water level forced by the government, they will at a certain level observe losses with their current way of farming. In this case they will give up their business or they can use cattail cultivation as reasonable alternative since it delivers small profits. Although it turned out that there is positive margin possible for farmers in wet areas, cattail cultivation is not able to convince the farmers to change their farming system on a voluntary base, because its profit is by far too low. Therefore, the resistance of farmers will remain when there are any movements of inundating agriculture areas. However, based on the model calculation, cattail is an alternative to appease affected farmers.

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7. Discussion 7.1. Growing conditions In this report, three cattail species (T. latifolia, T. angustifolia and T. × glauca) which are suitable for cultivating in the northeast of Friesland were introduced and their growing conditions were compared. Information is sufficient for T. latifolia and T. angustifolia, while little information was obtained for T. × glauca as few researches were performed previously. It is known that T × glauca is the hybrid of T. latifolia and T. angustifolia. Its characteristics are mostly intermediate to its parent species and mainly reproduce by vegetative spread. However, the biomass and the tolerance of water level, waves, salinity or pH remain unclear. In order to have a better understanding of T. × glauca, a field test is suggested for future research. Based on the current obtained information, T. angustifolia is found more tolerant of deeper water and saline soils than T. latifolia while they produce equivalent amounts of biomass. Therefore, it can be concluded that T. angustifolia is more suitable for cultivating in this program. Nevertheless, there is still a possibility that T. × glauca in fact performs even better than T. angustifolia. Therefore, further study should be performed with T. angustifolia and T. × glauca by comparing their biomass and tolerance ranges to give more precise recommendations on which species is most suited for cultivation in Friesland. An evapotranspiration rate for cattail varies from 100-300 cm, which is substantially more than conventional crops, such as corn which has a evapotranspiration rate 46-71 cm. It should be taken into consideration that during a summer time dry periods are likely to occur in Northeast Friesland. Therefore more research is needed on the consequences of the higher evapotranspiration rate of cattail in this area. 7.2. Growing locations The discussion of the results for growing locations involves several scales and as such is divided into different parts. 7.2.1. Provincial scale As is mentioned in Chapter 2 most of the province of Friesland is suitable for the cultivation of cattail, with the exception of the areas with Podzols. However, the spatial database used to determine the soil types has a very coarse resolution (5 km) and future research will benefit from a more detailed soil type map. Even though the soil type is not that important for the cultivation of cattail, the current map is over generalized and overestimates the potential area for cultivation. An underestimation of the potential area is made in the areas bordering the North sea, which at times suffer from salt intrusion. The higher water levels required for the cultivation of cattail would limit this intrusion. Combined with the tolerance that T. angustifolia has for saline conditions and with better water management, this could mean that even those areas currently classified as least suitable would then be moderately suitable for cattail cultivation. Finally, due to time constraints, for this scale level Triple C did not look at the Actueel Hoogtebestand Nederland (AHN) maps for less suitable areas since our focus was on those areas most suitable for cattail. However, suitable locations might still be found outside the Histosols, but they will likely require more pumping and more intense water management compared to locations with Histosols. 37

7.2.2. Regional scale For the NE-region only those parts of the AHN that contained a sufficient amount of Histosols were included. By not including less suitable areas, memory usage was kept low and various functions could be applied without long computation times. Even though only 25% of the entire region was included in the analysis, the number of suitable locations Triple C identified as part of the Histosols was substantial. Future research could again include the areas that were identified as less suitable if, for instance, a larger cultivation area is required than can be facilitated by the currently identified locations. Alternatively, for a more in-depth analysis of the current locations, more datasets could be used than were available for this project. A dataset of all the different roads in the region could be used to separate the region into different sections that are completely enclosed by roads. Then a buffer, a function in Arcmap, can be used to select locations close to the roads that indicate the maximum water level. This approach allows for an automatic and unbiased selection of the maximum allowable water level for each section, as opposed to the current method where the lowest position close to or part of a road is identified manually. Another spatial dataset that could be used in future research is one that indicates which areas are under the same water management. In this way the effect of changing the water level in one polder can be estimated more accurately. In addition to this, if the current maximum water level is also included in the dataset, the increase in the water storage capacity can also be calculated from such a dataset. 7.2.3. Veenwoude The current results for the Veenwoude area are obtained by using criteria and selection methods specific to its location and circumstances. Although this method resulted in a satisfactory result, it is not an approach that should be used to analyze multiple areas. This method relies heavily on the analyst’s personal interpretation of the area and surrounding locations and is not only biased but also very time consuming. The current results are also based on several assumptions, for which no official guidelines or benchmarks could be found, such as: a safety margin of 85 cm between the highest allowable water level and the lowest road section is assumed to be enough, but no basis for this assumption could be found. The same is true for the maximum allowed difference in water level between one (section of a) polder and another section which is why Triple C used a difference of 0 cm in our calculations. This would also keep the necessary extra pumping, to get additional water into the storage polder, to a minimum. On the other hand it greatly reduces the storage capacity, so finding more information on these topics would be very useful. Last of all, no information could be found regarding the current highest water level in the Veenwoude area, making calculations of the extra storage capacity obtained by flooding it even less reliable. Some indication of the wintertime water levels in the Veenwoude area would make these calculations a lot more accurate and the same is true for any other location that is to be evaluated. 7.2.4. Natural locations The suitable locations that were identified to find artificial growing beds apply to natural stands as well. Due to a lack of freely/publicly available datasets we are not able to give more than a very broad indication of where natural stands can be found. This is why for future research a dataset

38 which consists of all the water bodies in Friesland, would be very valuable. Just as with the road dataset that was mentioned earlier, a buffer could be created around the streams and lakes to indicate potential locations for natural stands. Although not all of the potential area will be populated with cattail, once the locations are identified, a verification study can be carried out to determine which fraction of the potential locations features cattail. This fraction can then be used to estimate the total area covered by natural cattail stands. 7.3. Artificial growing beds Cultivating cattail is a topic where several researchers have experimented with. At the moment, these experiments have not been carried out in the Netherlands, although they have been carried out elsewhere in the world (e.g. Germany and North-America). Results gained from these experiments are based on a relative short study period, with a maximum of four years. The hydrology has a great influence on cultivating cattail and on the (ecological) restoration of peatlands. But so far hydrological monitoring is not included in these researches. Hence, little information is available about the influence of cattail on the long-term scale. Within the experimental period, T. latifolia and T. angustifola were able to build up closed stands within a year under the associated local environmental conditions. Still, each year a loss is included during the growing cycles, either before or after harvesting. Additional research should focus on the development and especially on the stability of stands in Northeast Friesland. All the results of the regeneration experiments in peatlands have shown that the course of such processes is highly individualistic. Each case study is considered to be an individual system, which makes the final state, including the time span needed to reach it, hard to define. With only references available from experiments in foreign countries, it is not easy to predict how the suggested system will behave under Dutch circumstances. Along with having an influence on the restoration of wetlands, cattail is likely to have an influence on wastewater. Currently used conventional wastewater systems involve large capital investments and operating costs, and for that reason these systems are not a solution for farmers/villages. Constructed wetlands are gaining in importance as an effective alternative for the treatment of septic effluents. Compared with conventional treatment systems, wetlands can be established in the same place where the wastewater is produced; can be maintained by relatively untrained personnel; have relatively low energy requirements; and are low cost systems (Ciria et al., 2005). The presence of cattail leads to an increase in wetland performance. Results of these studies could have a persuasive effect on the farmer and government to remove pollutants efficiently from for example agricultural wastewater. After removal of the pollutants water can be used for drinking or irrigation practices. This system could be of a particular interest during summertime, during the maximum purification period of wetland. Still, experimental studies found different results regarding to the role of cattail in a constructed wetland for wastewater treatment. Although a general agreement is made on the need for harvesting to remove pollutants efficiently, uncertainties are still present, additional research testing is needed regarding the variation of the retention time in the bed in order to improve the efficiency of the system. Another thing which needs to be considered is that building the growing bed into separated blocks is good for field management and harvesting, which could also improve nutrient distribution. 39

However, building separated blocks would increase the complexity of internal water system within growing bed, which means farmers will spend more for building and maintenance. The landing shore is suitable for both harvesting boat and conventional harvesting machine. The growing bed design still needs a water measuring tool and the valves for it. The pumps could be designed with solar energy power, which is better for energy consuming and sustainable development but is more expensive to build and maintain. In our design of an artificial growing bed for cattail, the specifications were made based on the requirement of cattail growth and water management. To carry on the growing bed work, however, we still need more research on the feasibility and actual situation, such as local terrain, animal habitat and local transportation. Also, there is still some essential information which needs to be acquired. For example, the optimal density for cattail cultivation, which is closely related to the growing bed design, needs to be identified and the volume and size of ditches needs to be adapted to the actual situation. 7.4. Harvesting In literature the possible cattail harvesting methods discussed involve the use of conventional machinery. The use of conventional machinery is damaging for both soil and remaining stalks. Additionally, these machines can only harvest cattail during winter time when the water levels are low. but the main goal of the project is to increase water storage capacity during winter time and so to raise the water level. On the other hand, harvesting with conventional machinery is currently cheaper than less explored alternative harvesting methods; the ones that utilize the water. Harvesting with boat has so far only been used to remove weeds and other pests from water, but never to harvest crops with large stems and leaves which are harder to harvest, compact and transport. To serve both the purpose of harvesting around October, for a better stem and leaf quality, while preventing soil and land damage and serving the purpose of water storage during winter time it is the most interesting to explore harvesting by boat. In order to do so, current harvesting boats should be modified to more easily handle large stems and leaves to speed up the process of harvesting. For natural growing locations this would not be interesting as a minimum water level of 50-70 cm is required to harvest by boat, which does not occur in natural growing locations. 7.5. Market identification For a successful implementation of a production chain for cattail, it is important to have final products which can be marketed profitably. In order to identify whether cattail can deliver valuable products, the Dutch market opportunities of using cattail as raw material for either the production of insulating material or bio laminate were investigated. The focus was chosen on these two products since they were expected to be the most valuable opportunities. The first outcome is that the market data of these products is hardly available without charge. Investments into existing market analyses would exceed the budget limit of Triple C by far and hence could not be used. From the information that was accessible the following conclusions are drawn. The market for insulating material is a big market in which mineral or synthetic materials are the most important source for production. The natural sources for insulating materials are of less importance in the Netherlands. At first, this is due to the conventional attitude of the insulating market and the higher prices of natural laggings. Besides comparable insulating values natural

40 insulating materials need additional values to compensate the higher prices. Secondly, the Dutch serial construction manner is not considering natural laggings. The complexity of certificating natural insulating materials is seen as the last reason for the low share of natural laggings. Nevertheless, cattail laggings have appropriate aspects that could allow a successful marketing. Their insulating values are comparable to other conventional materials and on top of that they have additional benefits, so that they are sound-proofed and mould growth-resistant. Moreover, their production procedure is more environmental, often easier, and less harmful than glass fibre products. The sum of these aspects therefore should be promoted in order to market cattail based laggings profitable. As cattail insulations are still in the research phase it is at the moment too early to make recommendations on how to place the product on the market. The idea to focus on insulating materials from cattail should be pursued, and there is a large market for it. This means that in case of successful marketing also large demands are possible which in turn would allow expanding the cultivation area resulting in higher water storage capacities. As a conclusion, the possibility of using cattail for insulating material should be further pursued. Future research is necessary to identify how cattail based insulating products can be promoted and more crucial in which field of application they are best placed. Therefore also a better access to meaningful market data should be organised. Regarding the use of cattail as bio-laminate there is a disappointment. Against expectations cattail is not suited to use as base layer. Hence, it cannot replace the currently used wooded base layers and therefore cannot exploit demands of a niche market of the Netherlands and the large market in the neighbouring Germany. However, cattail can be used as design layer on floorings which allows marketing it for relatively high prices and results into a profitable margin for processing plants. Although the approach of using cattail as design can be extended to other markets, the demand for this special design is expected to be limited. This means that a production chain only based on the marketing of design layers would restrict the cultivation areas and thereby the water storage capacity gained by flooded areas. Still, this approach is auspicious as it allows a worthwhile marketing way of cattail, but the quantities that can be marketed will be limited. Therefore a production chain only based on this product is most likely not able to significantly increase the water storage capacity. Altogether, it can be concluded that are possibilities to develop worthwhile products using cattail as raw material. This is a crucial base for developing a production chain for cattail and therefore simultaneously an important step towards solving the water problems in Northeast Friesland. 7.6. Cultivating cattail on agricultural land By looking at the beginning of the desired production chain, farmers in Northeast Friesland are important stakeholders, as they are depending on the areas that are potentially going to be flooded. For the purpose of compensating them it is necessary, that growing cattail is a lucrative alternative to the actual situation of farming Friesland. At the moment dairy farming is the most important way of agricultural production in Northeast Friesland even holding a share of 17% of total dairy farms in the Netherlands. Moreover, the most important crop is grassland sharing 80% of all arable areas. By this, it is concluded that grassland is the crop to which the cultivation of cattail should be compared. In the further investigation two situations have been introduced. The first situation is grassland 41 cultivation under currently conditions which is evaluated with a profit of 800 €/ha. A second situation refers to wet conditions, which is included in case that increasing the water level in areas of Northeast Friesland is necessary. Under wet conditions, dairy farming is not profitable and results in a loss of 500 €/ha. At this point it needs to be said, that these reference values are based upon different investigations. For a more significant statement on this part, better researches at the desired local areas are necessary. However, these values are further used to compare the actual farming situation with the implementation of growing cattail. Due to the fact that cattail cultivation has not yet been explored in the Netherlands, estimations have been made on how cultivation would look like financially. The model calculation resulted in a profit of 83 €/ha for cultivating cattail. This finding is important as it shows that cattail can be grown with positive margins. This also means that such cultivation delivers an economic value to the area which is flooded for cattail. Yet, by comparing the profit to the 800 €/ha gained with farming under actual conditions, farmers deciding on economic considerations will not change to consider cattail cultivation as alternative as it would mean a loss of income. However, if their situation changes so that they have to work under wet conditions, the actual way of farming will result into a loss of 500 €/ha. In this scenario cattail indeed is a lucrative alternative as it still delivers a positive profit and thereby is preferable to dairy farming. Nevertheless it has to be said that the used model calculation is based on a set of assumptions which have to be investigated under the circumstances in the desired locations. If some of them are not chosen correctly, the profit may change significantly. This then might change the statements that have been drawn so far. Moreover, this model calculation fully neglects subsidy measures that are established under certain conditions on the Dutch agricultural sector. At the one hand this makes the assessment of cattail cultivation irrespective of political influences. On the other hand, the profit is consequently lower resulting in other conclusions than with considering subventions, which are given e.g. for sustainable farming. As a conclusion, cattail has the opportunity to gain profit to the farmer. Yet, this profit is too low to achieve an autonomous willingness to change the farming structure away from the more yielding dairy production towards producing with flooding. If the conditions change towards farming under wet conditions, then the farmers are either forced to stop business or can cultivate cattail as it still delivers a small profit. However, before the conditions are changed in this way farmers will keep up resistance to higher water levels, because cattail cultivation is not able to achieve the income farmers currently have. Therefore it is crucial to maintain including farmers in further considerations of solving the water problems of Northeast Friesland.

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8. Conclusion In this report, Triple C designed a theoretical model of cattail production chain in Northeast Friesland and hereby focuses on the farmer, processor and market are essential aspects. From the farmer´s perspective T. angustifolia was recommended as the most suitable species to cultivate in Northeast Friesland. Another promising candidate T. × glauca, which is the hybrid of T. angustifolia and T. latifolia, might produce more biomass and is more able to adapt to Dutch environmental conditions than both parents due to the heterosis. Based on cattail general determination of growing conditions, potential cattail growing locations were identified. However, due to the lack of accessible databases, it is not possible to give a more detailed indication. Hence, lots of research is still needed. Our theoretically based design of an artificial growing bed to cultivate cattail was made based on the requirement for cattail to grow and water management. More research about the actual situation in Friesland is required. Data on local terrain, animal habitat and local transportation are needed to improve the theoretical model for Dutch application. For harvesting cattail conventional machinery is cheap and more applicable, while harvesting by boats could be a promising choice considering preventing soil and stalk damage and increasing water storage capacity. Processors can use cattail as raw material to produce insulation material and modify bio- laminate. Moreover, the production procedures are safe and environmental friendly. Hence, processing lucrative products based on cattail is feasible. In the marketing research, cattail included bio-laminate and insulation board are found to be promising valuable products. Therefore, cattail provides opportunities to economize vegetation in the wetlands. However, it is uncertain whether the estimated profits are enough to encourage farmers to start cultivating cattail. Thus, raising awareness amongst farmers of the problems of the current water management is crucial for the future plan. Altogether it can be concluded that cattail succeeds among all the relevant sections of the production chain. By using cattail it is indeed possible to re-economize wetlands.

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