Appendix Two

GROWTH CHARACTERISTICS AND YIELD OF

EUROPEAN FIBRE FLAX (Linum usitatissimum L.)

CULTIVARS IN MIDWESTERN ONTARIO

Environmental Sciences Western Field Station University of Western Ontario| 2011

Copyright 2012 Northwest Middlesex Multi-Service Centre. All rights reserved.

Refer to this publication as: Stewart, C. (2011). Growth Characteristics and Yield of European

Fibre Flax (Linum usitatissimum L.) cultivars in Midwestern Ontario: Final Report. Parkhill,

ON: Northwest Middlesex Multi-Service Centre

The material contained in this report has been prepared for the Northwest Middlesex Multi-

Service Centre. We make no representation or warranty, express or implied, as to its accuracy or

completeness. In providing this material, Northwest Middlesex Multi-Service Centre does not

assume any responsibility or liability.

The field trials conducted at the Environmental Sciences Western Field Station, University

of Western Ontario were part of a Fibre Flax Labour Market Partnerships (LMP) Project.

The purpose of the Fibre Flax LMP Project was to demonstrate that the reintroduction of fibre

flax to Midwestern Ontario is feasible from an agronomic perspective and is also a potential

generator for sustainable employment.

The project is administered by the Northwest Middlesex Multi-Service Centre in partnership

with representatives from Employment Ontario; Northwest Middlesex Multi-Service Centre;

Environmental Sciences Western Field Station, University of Western Ontario; and Huron

Business Development Corporation. An advisory committee oversaw the project, with additional

representatives from Edy’s Mills

Experimental Sciences Western Field Station, University of Western Ontario Team:

Field Station Manager Peter Duenk

Agronomist/Researcher Christie Stewart

Research Technician Caroline Rasenberg

Research Assistant Joel Vanhie

This Employment Ontario project has been funded in part by the Government of

Canada. The views expressed in this document do not necessarily reflect those of the

Government of Canada.

Growth characteristics and yield of European fibre flax (Linum usitatissimum L.) cultivars

in Midwestern Ontario

Introduction

Brief history and current state of fibre flax cultivation

Flax (Linum ustitatissimum L.) is one of the oldest crops in the world dating back 9000

years before present, with cultivation origins somewhere in the Near East (Roseberg 1996; Cullis

2007; Diederichsen and Ulrich 2009). More recently, fibre flax cultivation has been concentrated

in central European countries, as well as, China, Egypt, Turkey, Chile and Argentina, where

warm and moist climatic conditions for growth are ideal (Cullis 2007; FAOSTAT 2009). In 2009,

a total of 457,894 tonnes of fibre flax were produced globally (FAOSTAT 2009). Traditionally,

end product use of fibre flax has been as a natural fibre textile, where it currently comprises 3%

of global natural fibre production. Flax was grown by early North American settlers in the 1600s,

mostly for textile purposes and, to a minor extent, to produce seed (Roland 1913; Canada

Dominion Bureau of Statistics 1919; Cullis 2007). Its use for purposes other than linen and seed

was considered as recently as the early 1900s in Canada (Roland 1913; Canada Dominion

Bureau of Statistics 1919). However, investigations into fibre flax use in a variety of bioproducts

to create value-added or alternative products have become more prominent in the last 30 years

(Dimmock et al. 2005; Natural Capital Resources Inc. 2005; Cullis 2007).

In North America, fibre flax has been cultivated at some point in nearly every state east

of the Mississippi River, as well as North Dakota, Mississippi, Oregon, British Columbia,

Alberta, Saskatchewan, Quebec and Ontario (Mühleisen 2000; Meyers 2002; Anthony 2005;

Bailey-Stamler et al. 2007). Expansion of the fibre flax industry in Canada was attempted by the

Department of Agriculture in the early 1900s. Their experimental work assessed the complete

development of the fibre flax industry in Canada, from cultivation to product manufacturing

(Canada Dominion Bureau of Statistics 1919). It was determined that fibre flax could be grown

successfully in Eastern Canada, however Western Canada did not have suitable growing

conditions for fibre flax due to an unfavourable climate (short season, early/late frosts, dry

conditions) (Canada Dominion Bureau of Statistics 1919). Its historical importance as an

industry in Canada is highlighted by its required use in large quantities in aeroplanes wings

during the First World War and the exemption of experts involved in the flax industry from

military service (Canada Dominion Bureau of Statistics 1919).

Fibre flax was once an extensive industry and significant component of Ontario’s

economy. In the early 1900s, its acreage expanded rapidly in Ontario with support from the

government. Acreage doubled from 4,000 acres in 1915 to 8,000 acres in 1917. In 1918, the

value of flax for seed and fibre in Ontario was estimated at $1,984,000 in 1918 dollars;

approximately $27,637,000 value in current dollars (Canada Dominion Bureau of Statistics 1919;

Bank of Canada 2011); up from $399,600 in 1915 for fibre, seed and tow (Canada Dominion

Bureau of Statistics 1919). The crop was used for fibre, tow and seed in the province (Canada

Dominion Bureau of Statistics 1919). The largest flax cooperative was in Windsor, Ontario

(Manufacturers’ Co-operative Agricultural Association of Windsor, Ontario) which processed

much of the fibre flax grown in East Middlesex, Ontario (Canada Dominion Bureau of Statistics

1919). Currently, flax is a minor crop in Ontario that was reduced from 74100 acres in the 1950s

to less than 2,470 acres between 1999 and 2009 (Upfold and Hume 1984; OMAFRA 2011).

Clearly, fibre flax cultivation and processing was once a profitable and widespread

industry in North America, however, production mostly disappeared by the mid-1900s following

the Second World War. This was due to the loss of government subsidies for growers, the

introduction of petroleum-based synthetic fibres and technological developments and subsidies

in the cotton industry (Roseberg 1996; Samson et al. 2004). Currently in the European Union

subsidies lower costs of growing fibre flax by 30%, making cultivation economically viable

(Cullis 2007). Low crude oil prices also made the use of synthetic fibres more economically

profitable than the use of natural fibres, such as linen. Commercial production in the United

States has been maintained in North Dakota, Minnesota and South Carolina due to the

requirement for a fast-growing, cool season crop, where fibre and seed cultivars are grown

(Meyers 2002; Foulk et al. 2003).

In Ontario, recent experimental trials were conducted with European flax cultivars to

assess their suitability for the long textile fibre industry; however, the research sites were more

northern than the proposed study site (Scheifele and Davies 2001). The cultivation of flax for use

as a biofibre has also been assessed in Eastern Ontario and Quebec as part of the emerging

biofibre market, as well as the textile industry (Couture et al. 2002; Couture et al. 2004; Natural

Capital Resources Inc. 2005). Each study showed significant promise for the cultivation of

European cultivars for the reintroduction of fibre flax under the conditions tested.

The majority of the current flax industry in Canada is focused on oilseed crop production

in the western part of the country. Manitoba, Saskatchewan and Alberta are the three greatest

oilseed flax producing provinces in Canada with yields of 193,000, 708,700 and 28,400 tonnes in

2009/2010, respectively (Flax Council of Canada 2011), comprising of 30% of the global oilseed

flax production in 2009 (FAOSTAT 2009). As such, the majority of scientific information on

flax in Canada is focused on oilseed flax cultivars and information regarding fibre flax

cultivation in Canada is lacking.

Uses of fibre flax

Increased interest in renewable and natural fibre products provides the opportunity for

revitalization of the fibre flax industry in Ontario (Couture et al. 2002). In addition to the use of

flax fibres, whole-plant biomass, which includes non-fibre components, has the potential to be

used in various value-added products (Natural Capital Resources Inc. 2005). Since only 20% of

the stem weight is used for textiles (Mustata et al. 2006), the eliminated 80% can be used for

other purposes. Oilseed flax also has a similar potential for multi-use purposes. Flax straw from

oilseed crop contain short fibres, which is an undesirable quality for fibre use in the textile

industry (Dimmock et al. 2005; Burton 2007). Flax straw remaining after seed harvest from

oilseed flax is typically burned; though to provide a value-added product, it is sometimes used

for paper products, such as cigarettes (Bailey-Stamler et al. 2007; Smeder and Liljedahl 1996).

More recently, dual-use cultivars of flax (seed and fibre) have been under investigation for

commercial production (Dimmock et al. 2005; Cullis 2007); however, the suggestion of using

oilseed flax in Canada for multiple purposes is not new, as alternative uses can be dated back to

the early 1900s (Roland 1913).

The target plant tissues of fibre flax used for the textile industry are long fibres found

between the epidermis and the cortex of the stem (Akin et al. 1996; Akin et al. 2009). Initial

release of short and long fibres from non-fibre components occurs through a degradation process

called retting. The majority of commercial-scale retting occurs through natural microbial

weathering (dew-retting), while some producers use immersion in water (water-retting),

artificially applied enzymes (enzyme-retting) or chemical retting to release the fibres (Campbell

1990; Bennett et al. 2007; Akin et al. 2009). Traditional biological retting (dew-retting) is a long

process that is dependent on climatic conditions (Anthony 2005). It can take up to several weeks

for the retting process to be completed under optimal conditions (Ebskamp 2002). However,

application of a dessicant herbicide, such as isopropylamine salt-based glyphosate with

biactivator, allows for an early harvest with enough time for seed maturation to occur so the

seeds can be used as a value-added product, in addition to the fibre (Bennett et al. 2007).

The rest of the fibre flax stem (i.e. shives, short fibres [tow]) can be used in bioproducts,

such as industrial fibres for construction materials, geotextiles, fibre blends and biofuels (Natural

Capital Resources Inc. 2005; Bennett et al. 2007; Harwood et al. 2008; Algoma District Oilseed

and Fibre Crop Initiative 2009). For example, flax short fibres can be used in plastic composites

for automobile parts (Horne et al. 2008). In Europe, demand for fibre flax for this type of product

has experienced an annual increase greater than 50% and domestic demand is expected to grow

as well (Flax Council of Canada 2011). Tow can be combined with cotton fibres through a

cottonization process and used for lower quality textiles (Das et al. 2010). Fibres can also be

used for insulation products to replace fibreglass (Horne et al. 2008). Shives can be used for

particleboard and hardwood composites, replacing petrochemicals, thereby reducing associated

negative environmental impacts (Smeder and Liljedahl 1996; Flax Council of Canada 2011).

Removing fibres and shive from flax straw does not necessarily require a retting process

if the fibres are not intended for high quality textiles. The use of modified cotton gin technology

to remove fibres has been applied with relative success; 13.8% fibre yield out of a possible 20%

(Anthony 2005). The use of this technology would reduce the time and uncertainty associated

with the retting process. In addition, there is reduced concern for maintaining fibre quality for

industrial uses as the required fibre characteristics differ from those for the textile industry

(Smeder and Liljedahl 1996). However, without retting, a limited amount of bast fibre is

extracted (20-80%) that is not as clean or fine as fibre that has been retted (Ulrich 2004). Bennett

et al. (2007) demonstrated that extending time to harvest does not reduce fibre quality if the

fibres are intended for industrial purposes. This allows the capsules (seeds and seed pods) to

mature, which can then be removed and the seed can be used for animal and poultry feed (Cullis

2007), providing a value-added product.

Flax has also been shown to have potential use for phytoremediation of sites

contaminated with heavy metals and petroleum hydrocarbons using on-site plant growth

(Angelova et al. 2004; Ravanbakhsh et al. 2009) or removal of tricholorethylene using activated

carbon derived from flax shives (Klasson et al. 2009). Due to varied distribution of heavy metals

in flax biomass, crops grown for heavy metal phytoremediation still have useful components for

industrial products as there is no effect on crop yield or product quality (Angelova et al. 2004).

Different flax cultivars vary in fibre characteristics (e.g. diameter, total content) and other growth

dimensions (Booth et al. 2004, Diederichsen and Ulrich 2009), though the agronomic factors that

have the greatest effect on fibre quality are ill defined (Dimmock et al. 2005). Therefore, the

cultivar of choice will be determined by the sought after end-product since the desired qualities

of fibre flax, including the bast fibres and shives, are dependent upon specific cultivar

characteristics.

Reintroduction of the fibre flax industry in Ontario

The reintroduction of fibre flax in Ontario is stimulated by several factors; primarily

concern for environmental impacts associated with agricultural inputs, rising costs and economic

growth through job creation. Flax cultivation often does not require large amounts of inputs, such

as pesticides and fertilizers (Anthony 2005; Dimmock et al. 2005). For example, fibre flax does

not have a high nitrogen requirement; therefore, a limited amount of additional nitrogen is

needed if there is residual soil nitrogen from prior fertilizer application or nitrogen credit from a

previous leguminous crop (Franzen 2004). Compared to high-input crops, negative

environmental effects can be reduced directly and indirectly if fibre flax is grown through

decreased application of inputs, decreased fuel consumption by application equipment and

resultant greenhouse gas emissions. Reduced inputs also reduce costs associated with fibre flax

production. Cotton, though a renewable fibre requires large amounts of pesticides that have

associated negative environmental impacts and also high associated costs (Liebman et al. 2001;

Pimentel 2005). Fibre flax is a less impactful alternative in terms of required inputs and

associated negative effects. The recent rise in energy prices has further encouraged interest in

renewable biofibres (Natural Capital Resources Inc. 2005). As energy prices increase, petroleum-

based textiles, such as polyester and nylon, will become more costly to produce, process and

manufacture.

Several opportunities arise with the reintroduction of fibre flax industry in Midwestern

Ontario, including crop diversification and economic expansion, which would lead to direct and

indirect job creation, particularly for rural communities. Economic expansion would not be

confined to the agricultural and textile industries. It would include opportunities for the

development of end products in the alternative fuels and composites industries and for the

production and operation of equipment associated with processing flax products in the

manufacturing industry. A farmers/producers cooperative model was suggested in areas in South

Carolina, where unemployment and poverty rates were considered high in the mid-to-late 90s to

improve the regional and local economy (Foulk et al. 2002). The processing plant in Kingstree,

South Carolina was completed in 2001 and had recently been leased to Naturally Advanced

Technologies Inc. for decortication of their organic flax fibres known as CRAiLAR® (Naturally

Advanced Technologies 2010). In addition to economic benefits, revitalization of the fibre flax

market would also provide a domestic source of fibre for current textile needs and other

emerging and growing bioproduct markets.

Diversification in crop rotation is important because it reduces the buildup of pests and

diseases, reduces selective pressures that promote the development of pesticide resistance and

aids growers in implementing integrated pest management strategies and soil conservation

techniques (Swanton and Weise 1991; Liebman and Dyck 1993; Magleby 2002; Anderson 2005;

Anderson 2008). Additional crop options also increase flexibility for growers, allowing them to

better respond to annual changes in climatic conditions and fluctuations in global market prices

for crops. It is recommended that fibre flax not be grown more than once every three to four

years, therefore fits well into a typical crop rotation practices used in Ontario (Canadian Food

Inspection Agency 1994). A 4-year rotation, such as wheat-flax-corn-soybean, maximizes crop

diversity and interferes with crop-pest associations greater than a 3-year rotation (Peel 1998).

Flax can be grown in rotation following cereals or corn (Flax Council of Canada 2011), though

some difficulty with flax seedbed preparation may occur following corn due to the residue from

the crop (Irwin 1998). Flax is sensitive to root diseases such as Fusarium wilt and Rhizoctonia

diseases, which can occur following a previous flax crop, soybean, potatoes or sugar beets.

Therefore, it is recommended flax not be planted following these crops. Flax may also grow

poorly after canola or mustard due to toxic compounds released by the crop residue of both

plants (Canadian Food Inspection Agency 1994; Flax Council of Canada 2011).

Project boundaries and justification

This project is part of a larger project focused on the reintroduction of the fibre flax

industry in Midwestern Ontario. This component of the research has not assessed the quality of

the bast fibres and other flax components for product suitability, as it is only intended to assess

agronomic aspects of flax growth. Another component of the larger project will assess fibre

characteristics related to cultivar and climatic/soil factors. To date, no recent agronomic studies

of fibre flax have been conducted for Midwestern Ontario. Previous fibre flax cultivars

historically grown in this region originated from European sources, though there have likely been

genetic changes in the cultivars due to selection and breeding programs since they were grown in

the late 1800s – early 1900s. In addition, climatic and soil factors interact with genetic

differences to affect flax growth, yield and fibre quality (Alvarez 2010; Booth et al. 2004;

Diederichsen and Ulrich 2009). Therefore, current commercial fibre flax cultivars grown in

Europe need to be reassessed for cultivation suitability in this specific region and for specific end

use products before large-scale reintroduction can occur. In order to appropriately assess fibre

flax as a viable industry in this region, the best adapted cultivar(s) with the greatest yield

potential and other desired plant qualities need(s) to be determined through agronomic study.

Materials and Methods

The seed of twelve fibre flax cultivars and one dual-purpose cultivar were obtained from

various sources and planted in experimental trial plots on May 11, 2011 at the University of

Western Ontario Environmental Science Western (ESW) Field Station, London, Ontario (11km

northwest of the University of Western Ontario, ON, 43°04'25''N latitude, 81°20'11''W longitude)

(Table 1). The fibre flax cultivars selected are considered premium for fibre flax production in

different parts of Europe and the cultivar, Bethune, has shown great potential as a dual-purpose

crop in the Canadian Prairies (H. Becker, pers. comm.). Land was ploughed the previous autumn

and in the spring the plots were cultivated three times to prepare seed bed and incorporate

fertilizer using a Kongskilde cultivator with rolling harrows. The previous crop was potatoes.

Soils tests were performed to determine fertilizer needs. All plots were broadcast fertilized on

May 10, 2011with 40 kg/ha of N, 28 kg/ha of P, 20 kg/ha K, 9.09 kg/ha Mg and 9.09 kg/ha of S.

The soil at this location was classed as Bryanston silt-loam (Agriculture and Agri-Food Canada

1992). Precipitation was monitored at the ESW Field Station.

Planting occurred later than what is typical for fibre flax in European countries (typically

March or April) due to abnormally wet conditions in April and May that prevented soil

preparation and planting (Table 2). Plots were arranged in a randomized complete plot design

and replicated 4 times. Experimental plots measured 6.0 m in length by 1.5 m in width (Figure 1).

Germination tests were used to determine mortality rates of each variety, which was used to

calculate the 1000 kernel weight of each variety to establish differential seeding rates to achieve

a plant population density of 1800 plant/m2. This calculation was also adjusted for estimated

mortality of 5%. A small plot seeder with rows spaced 15 cm apart was used to plant the plots

(Figure 2). Two passes were used to achieve a plot width of 1.5m resulting in 10 planted rows of

flax in each plot. Seeding depth was approximately 1-2 cm and the seeds were covered by soil

and lightly packed with press wheels on the seeder.

Grass and broadleaf weeds were controlled using a tank-mix of sethoxydim (1 L/ha) plus

Assist oil (2 L/ha) plus MCPA 500 (1 L/ha) which was applied on May 31, 2011. Herbicide rates

were based on recommendations for Ontario for oilseed flax (OMAFRA 2010). Lady’s thumb

was suppressed and yellow nutsedge was not controlled by this tank-mix, which was expected

(OMAFRA 2010). Hand weeding was used to control weeds within each plot that were not

controlled by herbicide application. Hand weeding and rototilling were used to control weeds

around the plots.

Days to emergence were measured by visual inspection over the entire plot for

appearance of seedlings emerging through the soil surface. The number of days from planting to

the start of flowering was determined with the appearance of the first flower within each plot.

Mid-point of flowering was recorded when 50% of each plot had flowered. This was assessed by

visual estimation. The number of days to harvest was also recorded.

For each of the following measurements the outside row along the length of each plot

was excluded, as well as 50cm from the end of each plot to avoid edge effects. The number of

plants within two rows of a randomly placed 30 cm x 30 cm quadrat in each plot was counted.

This was repeated within each plot and the average between the two quadrats was used for data

analysis. Since the 30 cm2 quadrats represent 28% of the 1 m

2 quadrats, the densities determined

for the two rows was divided by 2 to represent one row, multiplied by 7 for proper proportional

representation, then converted to represent the density in 1 m2. Two or three rows could fit into a

30 cm2 quadrat depending on placement.

Plant height was measured from base of stem to highest point on 25 randomly selected

plants within each plot. This was done at 4, 8 and 11 weeks after planting (WAP). The plants at

11 WAP were hand harvested from the plots before measuring. The mean height of the 25 plants

from each plot was used for analysis. Stem diameter was also measured at 11 WAP on the same

plants used to determine plant height. This was determined by measuring at the base of the stem

at soil level using digital electronic calipers. Mean stem diameter of the 25 plants per plot was

used for statistical analysis. Branching was also assessed on these same plants. Presence or

absence of branching within the first 50 cm of each plant was recorded. This was then converted

to a branching ratio by dividing the number of plants that had branching by the total number of

plants assessed in the plot (25). These samples were used to determine fresh and dry biomass and

straw yield for the quadrat and then converted to t/ha. After recording fresh biomass, samples

dried at 65°C in a dryer until they reached a constant weight. Seeds were removed from the dried

flax straw by rippling from were weighed. Lodging was estimated visually by assessing the

proportion of each plot not fully standing at harvest on Aug. 2nd or 3rd.

Within each plot, plants within a 1 m2 quadrat placed near the centre of the plot were

hand harvested when two thirds of the lower leaves had been shed and one half of the stem had

turned yellow and spread on the soil surface to ret (Aug. 2nd – 4th). These samples were turned

weekly and removed from the field when retting was complete on Aug. 19th and stored in a dry

location for fibre analysis at a later date. The rest of the plots were hand harvested the following

week on Aug. 9th and 10th, spread on the soil surface to ret, then removed and stored in a dry

location when retting was complete (Figure 7).

Statistical analyses

All analyses were performed using SYSTAT Ver. 13 (SYSTAT Software, Inc. 2011).

Prior to any statistical analyses, normal distribution of the data was tested using the Shapiro-

Wilks test for normality. Homogeneity of variance was determined using by plotting residual

values and independence of errors was assessed using Durbin-Watson coefficients. Data that

were not normal were transformed accordingly. Fresh biomass was square root transformed and

height at 4 WAP was inverse transformed. When the assumption of normality could not be met

with transformation, a non-parametric Kruskal-Wallis test was performed (height at harvest).

Data that was normalized was assessed using an Analysis of Variance to determine differences

among cultivars and differences were separated using Fisher’s Least Significant Difference test

at the 5% level of significance. All data presented in tables have been back-transformed.

Results and Discussion

Meteorological data

During the months of April, May and June the experimental plots received 63, 111 and

7% more precipitation compared to the 30-year average for Ilderton, ON, respectively

(Environment Canada 2011; Table 2). July received 14% less precipitation than the 30-year

average. Average temperatures were close to normal, however, in July the temperature was

above 30°C for 12 consecutive days.

Flax growth phases

All cultivars emerged on the same day (Table 3). The vegetative phase lasted 58 days for

all cultivars except Chantal, which lasted 51 days (Figure 3). This is within the typical range of

45-60 days for the vegetative phase (Flax Council of Canada/Sask Flax 2002). Flowering started

between 49 and 52 days after planting (DAP) (Table 3). The flowering phase lasted 8-22 days, as

determined the mid-point of flowering x 2, however small number of flowers continued to bloom

up to harvest (Table 3). The usual flowering period for flax lasts 15-25 days (Flax Council of

Canada/Sask Flax 2002). Mid-point of flowering ranged between 53-60 DAP and most cultivars

had completed intensely flowering after 10 days (Figure 4). Drakkar had the longest flowering

period of 22 days (Table 3). The timing of maturation for harvest was within the expected 80-

100 day range for fibre flax (Flax Council of Canada/Sask Flax 2002; Table 3, Figure 5 and 6).

Chantal and Drakkar were not as physiologically mature as the other cultivars on Day 83, when

harvest began; however, they were at physiological maturity by day 85. This is likely a result of

the delayed mid-point of flowering of both cultivars compared to the other cultivars (Table 3).

Plant density

Plant density was significantly different among cultivars at 4 weeks after planting (WAP)

and at harvest, with Sofie having the lowest density for both assessment dates (Table 4). A low

germination rate of 88% may have resulted in reduced plant density of this cultivar (data not

shown). Density at 4 WAP and harvest ranged from 426 to 929 plants/m2 and 426 to 1016

plants/m2, respectively (Table 4). At harvest, the densities represent 24 to 56% of the target plant

density of 1800 plants/m2. This is lower than what is considered optimal for fibre flax at 1800-

2000 plants/m2, especially for production of long fibres, though closer to the desired stand

density of 800 plants/m2 for industrial fibre (Bennett et al. 2007, Easson and Molloy 2000). In

the months prior to and following planting, precipitation was 63 and 111% greater than the 30-

year norm (Environment Canada 2011; Table 2). This likely reduced germination and/or

emergence, and consequently plant densities of all cultivars from what was expected. Similarly,

Easson and Long (1992) found that very wet and cold conditions following seeding resulted in

reduced fibre flax establishment. Rossini and Casa (2003) also attributed low fibre flax densities

to poor soil and weather conditions, as precipitation was abundant and temperatures were

freezing just prior to planting. Plant densities were 20-40% of their target plant density. Plant

density has been reported to influence fibre quality, with increased fineness and quality at higher

densities (Booth et al. 2004, Easson and Long 1992). Easson and Long (1992) recommend a

plant density of about 1800/m2 to balance the tradeoffs between fibre quality, yield and lodging

risk. Seeding rate was adjusted for germination rate, mortality and varietal seed weight

differences. The estimated mortality of 5% may have been too low, resulting in lower stand

densities. Seed weight ranged from 4.53 g – 6.35 g/1000 seeds and germination ranged from 88-

100% (mean = 97%). Establishment shortly following emergence would better inform about

changes in plant mortality over time so that seeding rates could be adjusted for future plantings.

Plant height

Mean plant height was significantly among cultivars at 4 and 8 WAP, though differences

did not exist at harvest (Table 4). Vesta was significantly taller than all other cultivars at 12.29

cm four WAP. Greater height at this stage could provide a competitive advantage against weeds;

however, this needs to be assessed to determine if an advantage exists with greater height early

in the vegetative phase for fibre flax. Fibre flax does not compete well with weeds, which can

reduce yield (Friesen 1986). Increased plant height has been shown to improve crop

competitiveness against weeds (Balyan et al. 1991). High variability contributed to the lack of

significant differences in height at harvest, even though most cultivars had very similar heights.

Bethune was the shortest cultivar (65.33 cm). This was expected since Bethune is a dual-purpose

variety that has not been selected for height by breeders. Plant height of other cultivars ranged

from 78.99-87.70 cm. Sofie was the tallest cultivar at harvest, which can be attributed to low

plant density, as increased row spacing and decreased seeding rate can result in increased plant

height (Easson and Long 1992, Easson and Molloy 2000). For long fibre production, taller plants

are more desirable. Flax plant height is correlated with fibre length and fibre quality such that tall

plants have longer and higher quality fibres (Easson and Long (1992). The optimal length of

fibres for long line fibre for processing is between 50 and 100 cm (SaskFlax 2001).

Stem diameter

Some differences were found in stem diameter among cultivars though most were not

different from each other (Table 4). Bethune was found to have a greater stem diameter than

Marilyn and Suzanne. Bethune had the greatest stem diameter (2.75 cm) while Marilyn had the

lowest (1.78 cm). Low stem diameter can result from high plant density, though this relationship

can be dependent on cultivar (Booth et al. 2004, Couture et al. 2004). Marilyn had the highest

plant density that resulted in reduced stem diameter. While fibre content has been demonstrated

to increase with stem diameter and plant height, Bethune is assumed to have low fibre yield

despite have the greatest stem diameter among the cultivars based on an estimation of fibre yield

relative to its fresh biomass (Zhou et al. 1986, Table 4). Compared to the study by Couture et al.

(2002), stem diameter of the cultivars in this study were greater. This can be attributed to

reduced plant densities in this study.

Branching ratio

Branching ratio was not significantly different among cultivars (data not shown). Overall,

branching incidence was low, with an occurrence of 53 plants out of 1300 plants assessed for

branching. Fibre flax cultivars are intentionally bred to express reduced branching and seeding

rates are established at a high rate to limit branch formation.

Lodging

Only 6 of the 52 fibre flax plots showed evidence of lodging. This was not treatment

specific, as each one of the 6 represented a different cultivar. Lodging ranged from 5 - 40%;

however, it was less than 25% in 5 of 6 of the plots (data not shown). Lodging has been shown to

increase with high rates of nitrogen application. Dimmock et al. (2005) found an increase in

lodging when 80 kg/ha of N was applied to fibre flax and dual-purpose cultivars compared to 40

kg/ha of N, particularly under dry soil conditions. Lodging was not significantly different when

nitrogen application between 0 – 50 kg/ha was applied to the cultivars Belinka and Hera, and

ranged from 3.1-8.4% (Dimmock et al. 2005). The nitrogen amount applied in this study was

chosen within the range of recommended rates for fibre flax to limit lodging. Lower plants

densities than intended in this study may have also contributed to low occurrence of lodging

(Easson and Long 1992).

Fresh and dry biomass

Fresh biomass was significantly different among cultivars, though only Bethune (8.8 t/ha)

and Sofie (8.0 t/ha) had less fresh biomass than Drakkar (14.0 t/ha) (Table 4). Interestingly, with

the exception of fresh biomass and height at 4 WAP, other measured growth characteristics of

Drakkar did not differ much from the other cultivars. Drakkar may have had greater fresh

biomass at harvest because it was not as mature as the other varieties 83 DAP, resulting in

greater water content. In this study, mean fresh biomass of the cultivars was lower than the fresh

biomass of the cultivars found by Couture et al. (2002); however, mean dry biomass of unretted

fibre flax in this study was greater. Sofie had the lowest dry biomass (3.7 t/ha) and Drakkar had

the greatest dry biomass (5.2 t/ha). Dry biomass ranged from 37-50% of fresh biomass and did

not differ among cultivars. Couture et al. (2002) found that dry biomass was approximately 25%

of fresh biomass.

Straw yield

No significant differences occurred between cultivars for mean straw yield (Table 4).

Alizee had the highest straw yield (3.97 t/ha) and Electra had the lowest (2.83 t/ha). Straw yield

does not appear to be directly related to fresh or dry biomass of the cultivars, though this was not

statistically assessed. In contrast, van den Oever et al. (2003) demonstrated that straw yield does

directly relate to fibre production. Average straw yield is estimated at 1.2 t/ha in the UK to a high

of 6.8 t/ha in France (Weightman and Kindred 2005).

Fibre yield

While fibre yield and other fibre qualities have not been quantitatively determined in this

study, fibre yield can be estimated based on the assumption that 25% of the fresh weight is fibre

content (Roseberg 1996). Using this assumption, the cultivars assessed here could yield 2.0- 3.5

t/ha of fibre (Table 4). This is greater than the average 1.5-2.0 t/ha of flax fibre yield in Western

Europe (Roseberg 1996). However, Booth et al. (2004) indicated that fibre yield can range from

25% to 35% percent of fresh weight in the commercial cultivars they examined. Plant densities

in this study were less than those found by Couture et al. (2002). Increased plant density of the

cultivars studied here could result in increased fresh weight, therefore increased fibre yield, but

only to a point as tradeoffs with increased plant density occur beyond an optimal density. Higher

plant densities can reduce straw yield, fibre yield and increase chance of lodging (Easson and

Long 1992). Optimal plant densities for growth of the cultivars assessed in this study needs to be

determined for Midwestern Ontario.

Recommendations and conclusions

Testing the cultivars examined in this study at other locations with different soil types is

necessary to understand how this might affect straw and fibre yield and quality. Other research

has found that agronomic growth of fibre flax cultivars varies by location and soil type (Couture

et al. 2002, Easson and Molloy 2000, Sheifele and Davies 2001) With the understanding that

further assessment of fibre yield and quality is required to determine the appropriate cultivars for

reintroducing the fibre flax industry in Midwestern Ontario, and that the data represent only one

study year, some recommendations can be made based on the agronomic results. Due to low

plant density, resulting in low fresh and dry biomass weight, Sofie is expected to have low fibre

yield. However, Sofie was the tallest cultivar at harvest potentially containing more long fibre

than the other cultivars, which has the highest value of flax plant components ($1200-5000/tonne;

Ulrich 2004). Drakkar was estimated to have the greatest fibre yield based on a 25% estimate of

fresh weight, but its fresh weight did not differ from Agatha, Alizee, Chantal, Caesar Augustus,

Eden, Electra, Marilyn, Melina, Suzanne and Vesta. Each of these varieties has significant

production potential as a new crop for rotation in Midwestern Ontario.

This research indicates that current European cultivars and a dual-purpose cultivar grown

in the Canadian Prairies can be grown successfully in Midwestern Ontario. Based on rough

estimates, the cultivars used in this study all had greater fibre yields that found in Western

Europe. However, fibre quality cannot be determined through correlation with the agronomic

measurements collected. Different end products will have different characteristic and quality

requirements for each component of fibre flax (long fibres, tow, shives etc.); therefore explicit

recommendations for ideal cultivars cannot be made until this data is available. Further testing of

cultivars should be based on the results of fibre yield and quality assessment.

Figure 1. Experimental plot plan for fibre flax field trials at the Environmental Sciences Western Field Station, Ontario, 2011.

Figure 1 Legend

Assigned treatment number Cultivar Assigned treatment number Cultivar

1 Agatha 8 Electra

2 Alizee 9 Marilyn

3 Bethune 10 Melina

4 Chantal 11 Sofie

5 Caesar Augustus 12 Suzanne

6 Drakkar 13 Vesta

7 Eden

Figure 2. Small plot planter used for planting fibre flax trial plots at the Environmental Sciences

Western Field Station, Ontario, 2011.

Figure 3. Fibre flax cultivars during the vegetative growth phase at the Environmental Sciences

Western Field Station, Ontario, 2011.

Figure 4. Fibre flax cultivars during the flowering phase at the Environmental Sciences Western

Field Station, ON, July 4, 2011.

Figure 5. Fibre flax at maturation at the Environmental Sciences Western Field Station, ON,

August 24, 2011.

Figure 6. Fibre flax cutlivars following hand harvest at the Environmental Sciences Western

Field Station, Ontario, 2011.

Table 1. Country and company source for seeds of each cultivar

Cultivar Source Country

Agatha Procotex Corp. NV Belgium

Alizee Terre de Lin France

Bethune Freisen Seeds Ltd Canada

Chantal Van de Blitz zaden en vlas BV Netherlands

Caesar

Augustus

Dobebelaar Flax and Seeds Netherlands

Drakkar Terre de Lin France

Eden Terre de Lin France

Electra Procotex Corp. SA Belgium

Marilyn Wiersum Plantbreeding Netherlands

Melina Saneco France

Sofie Van de Blitz zaden en vlas BV Netherlands

Suzanne Van de Blitz zaden en vlas BV Netherlands

Vesta Saneco France

Table 2. Thirty year norms and actual precipitation and temperature records.

Month

30-year norm

Precipitation

(mm) a

Actual

precipitation

(mm) b

30-year norm

Average

Temperature

(°C)a

Average Actual

Temperature

(°C)c

April 85.3 139 7 7

May 87.6 185 13.6 14.5

June 85.4 92 18.7 18.4

July 82.3 72 21.1 23.2

August 96.1 110 20 20.6 a Data from Environment Canada 2011

b Data recorded at the Environmental Sciences Western Field Station, 2011

C Data from Environment Canada 2011 for London, ON

Table 3. Days after planting of emergence, first flowering, mid-point of flower and harvest for

each cultivar evaluated at the Environmental Sciences Western Field Station, Ontario, 2011.

Cultivar Days to emergence a Days to

flowering a

Midpoint of

flowering a

Days to

harvest a

Agatha 5 49 54 83-85

Alizee 5 49 53 83-85

Bethune 5 49 55 83-85

Chantal 5 52 57 83-85

Caesar Augustus 5 49 54 83-85

Drakkar 5 49 60 83-85

Eden 5 49 54 83-85

Electra 5 49 54 83-85

Marilyn 5 49 53 83-85

Melina 5 49 54 83-85

Sofie 5 49 54 83-85

Suzanne 5 49 53 83-85

Vesta 5 49 54 83-85 a Dates represent all 4 replicates. Differences did not occur among replicates.

Table 4. Comparison of cultivar means for plant density, plant height, fresh biomass, dry biomass and straw biomass for each cultivar

evaluated at the Environmental Sciences Western Field Station, Ontario, 2011. Cultivar Mean plant

density at 4

WAP

(plants/m2)

Mean plant

density at

harvest

(plants/m2)

Mean plant

height at 4

WAP (cm)

Mean plant

height at 8

WAP (cm)

Mean

plant

height at

11 WAP

(cm)

Mean stem

diameter

(mm)

Mean

fresh

biomass

(t/ha)a

Mean dry

biomass -

final yield

(t/ha)a

Mean dry

biomass of

straw (t/ha)b

Estimate of fibre

based on 25% of

fresh biomass

(t/ha) (Roseberg

1996)

Agatha 908 a 853 ab 9.01 bcd 79.69 ab 79.97 1.93 b 11.7 ab 5.0 3.84 2.34

Alizee 711 ab 862 ab 9.22 bcd 82.65 ab 84.42 1.97 b 9.8 ab 4.5 3.97 2.45 Bethune 551 ab 541 ab 8.44 cd 66.83 b 65.33 2.75 a 8.8 b 4.4 3.50 2.20 Chantal 654 ab 599 ab 8.28 d 83.27 ab 87.35 2.34 ab 10.9 ab 4.5 3.38 2.72 Caesar

Augustus 867 ab 726 ab 8.70 cd 87.06 a 86.15 2.11 ab 10.6 ab 4.5 3.20 2.65

Drakkar 742 ab 646 ab 8.35 cd 81.46 ab 88.50 2.12 ab 14.0 a 5.2 3.04 3.50 Eden 891 ab 654 ab 9.29 bcd 86.71 a 86.09 2.08 ab 10.0 ab 4.1 3.02 2.50 Electra 880 ab 738 ab 9.23 bcd 83.85 a 84.03 2.19 ab 10.0 ab 4.3 2.83 2.50 Marilyn 840 ab 1,016 a 9.05 bcd 79.72 ab 78.99 1.78 b 11.0 ab 4.7 3.43 2.75 Melina 825 ab 1,011 a 10.03 b 82.60 ab 81.17 2.05 ab 10.2 ab 4.4 3.08 2.55 Sofie 426 b 426 b 8.95 bcd 87.81 a 87.70 2.40 ab 8.0 b 3.7 3.45 2.00 Suzanne 677 ab 709 ab 9.41 bc 85.89 a 83.41 1.92 b 10.6 ab 4.6 3.50 2.65 Vesta 929 a 777 ab 12.29 a 86.24 a 84.36 2.03 ab 10.4 ab 4.5 3.39 2.45 Cultivar

significance *** ** *** *** NS ** ** NS NS

Means within a column followed by the same letter(s) do not significantly differ according to Fisher’s Least Significance Difference

test, p < 0.05. a includes capsules

b capsules removed

WAP, weeks after planting; NS, not significant.

*,**,*** Significant a p <0.05, p < 0.01, p < 0.001levels of probability, respectively according to the ANOVA.

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