Transcript
Page 1: Demonstration Project Report - Verschuren Centreverschurencentre.ca/images/2018/willow-report.pdf · 2018. 8. 31. · Demonstration Project Report Hybrid-Willow Short-Rotation Woody

Demonstration Project ReportHybrid-Willow Short-Rotation Woody Crops

Practice Guidelines and Procedure ManualDavid Alderson, Debi Walker, Stephen Kelloway, Lynn Baechler, Ross McCurdy, and Andrew Swanson

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AcknowledgementsThe Verschuren Centre for Sustainability in Energy & the Environment at Cape Breton University wishes to acknowledge the contribution and support of Enterprise Cape Breton Corporation, Lockheed Martin Corporation, Rendell’s Farm, and the following persons who enabled the success of the Hybrid-Willow Short-Rotation Woody Crop Demonstration Project, including:

Gerard ShawGary KozielEddie RendellBarrie FiolekBarry MacLeanLuciano LisiFrancis Allard

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Executive SummaryNova Scotians have an opportunity to re-establish the agro-forestry economy with a focus on export-orientated, high-value bioproduct production and marketing. There is ample capacity for the development of a large-scale commercial bioproducts industry in Maritime Canada; one that can take advantage of the regional infrastructure, free-trade agreements, regional academic and innovation-oriented institutions, commercially-orientated bioproduct research and development, and availability of renewable biomass feedstock resources.

In June 2010, the Verschuren Centre at Cape Breton University partnered with Enterprise Cape Breton Corporation to research and demonstrate the potential for hybrid-willow to be a value added cash crop to the agriculture and forestry sectors of Cape Breton Island. In 2011, the project was expanded to include an additional plot with partners, Lockheed Martin Corporation and Rendell’s Farm. The project aimed to generate knowledge in the development of biomass crops that could be grown on abandoned, underutilized or remediated lands. Short-rotation woody crops (SRWC) silviculture is characterized by high planting density (approximately 13,000-16,000 cuttings per hectare), periodic harvesting over a period of an approximately 25-year lifespan, with mean yields of 10 oven dry tonnes per hectare annually or greater.

The yield results of the Verschuren Centre’s hybrid-willow demonstration project confirmed that hybrid-willow plants can perform very similar in different planting conditions. Remediated sites can yield as much as agricultural lands within the first establishment years of the crop. However, further study and subsequent harvest rotations are required to determine if this trend will prevail over the willow’s lifecycle.

Overall, growth on the Broughton remediated mine site surpassed growth on former agricultural lands. The SX-64 and SX-67 varieties of hybrid willow outperformed Viminales, which was both observationally recognizable and confirmed in our harvest data. In the experimental trial, Fabius was the top performer at 22.1 odt/ha/year. Further trials of Fabius would be valuable to determine its commercial viability, along with SX-61 (16.8 odt/ha/year), Otisco (15.4odt/ha/year), SV1 (13.5 odt/ha/year), and Sherburne (13.3 odt/ha/year).

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Table of ContentsExecutive Summary ....................................................................................................... I

Table of Contents .......................................................................................................... II

Table of Figures .................................................................................................. III List of Tables ....................................................................................................... IV

1 Introduction ............................................................................................................... 1

2 CBU Hybrid-Willow SRWC Demonstration Project ................................................. 3

3 Advantages of Hybrid-Willow SRWC......................................................................... 6

4 Hybrid-Willow Varieties, Sourcing and Selection .................................................... 8

5 Site Selection ........................................................................................................... 11

6 Plantation Design .................................................................................................... 16

7 Establishment.......................................................................................................... 18

8 Schedule and Production Timeline ........................................................................ 25

9 Monitoring, Maintenance and Management .......................................................... 28

10 Harvesting .............................................................................................................. 36

11 Yield ........................................................................................................................ 39

12 Conclusions ........................................................................................................... 42

13 References ............................................................................................................. 44

Appendix

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Table of FiguresFigure 1 - Cape Breton University (left: October 11, 2011; right: October 27, 2011) ..................... 2

Figure 2 - Point Edward Farm (top left: May 30, 2011; top right: July 4, 2011; bottom left: October 27, 2011; bottom right: September 14, 2011) .............................................3

Figure 3 - A relief map of Nova Scotia showing elevation by hypsometric tints, (a gradation of different colours), and spot elevations (Natural Resources Canada, 2004) ...................9

Figure 4 - Optional double-row plot design dimensions for cultivating hybrid-willow (Abrahamson, Volk, Kopp, White, & Ballard, 2002) ..................................................... 12

Figure 5 - Egedal Energy planter (Egedal Maskinfabrik A/S, 2014 ............................................... 17

Figure 6 - Salix Maskiner’s Step planter (IGGESUND Holmen Group, 2013 ................................ 18

Figure 7 - Salix Maskiner’s Step planter (SUNY-ESF, 2004) ........................................................ 19

Figure 8 - Typical hybrid-willow production and maintenance timelines (Abrahamson, Volk, Kopp, White, & Ballard, 2002 ................................................................................ 21

Figure 9 - A multi-row rototiller used for weeding in the first growing season (Abrahamson, Volk, Kopp, White, & Ballard, 2002) ..................................................... 23

Figure 10 - Sickle bar mower (left) and rotary mower (right ........................................................ 25

Figure 11 - Pictures of insects and birds nest observed during the hybrid-willow demonstration project ................................................................................................. 28

Figure 11 - Willow forage harvester and bender harvester (Abrahamson, Volk, Kopp, White, & Ballard, 2002) ............................................................................................... 30

Figure 12 - Broughton site pre-harvest, Fall 2013 ........................................................................ 30

Figure 13 - CBU willow post harvest ............................................................................................. 31

Figure 14 - Hybrid-willow yield (tonnes per hectare) by trial location and variety, Cape Breton Island ...................................................................................................... 32

Figure 15 - Hybrid-willow yield (tonnes per hectare) by experimental trial variety ..................... 32

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List of TablesTable 2 - Available hybrid-willow varieties with commercially available varieties in a white

background and development varieties in a grey background (Abrahamson, Volk, Smart, & Cameron, 2009) ........................................................................................ 6

Table 3 - Optimal soil conditions for willow growth (Abrahamson, Volk, Kopp, White,

& Ballard, 2002 .................................................................................................................. 8

Table 4 - Site assessment ............................................................................................................... 10

Table 5 - Schedule of work and timelines ..................................................................................... 19

Table 6 - Weed management guidelines (Agro Énergie, 2010) .................................................... 24

Table 7 - Pests commonly observed on willow ............................................................................. 27

Table 8 - Hybrid-willow demonstration project yield results ....................................................... 33

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1 Introduction

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Nova Scotia has an opportunity to re-establish the agro-forestry economy with a focus onexport-orientated, high-value bioproduct production and marketing. There is ample capacity forthe development of a large-scale commercial bioproducts industry in Maritime Canada; one thatcan take advantage of the regional infrastructure, free-trade agreements, regional academic andinnovation-oriented institutions, commercially-orientated bioproduct research and development,and availability of renewable biomass feedstock resources.

The Verschuren Centre is taking steps to kick-start the expansion of Nova Scotia’s bioproductsindustry. The intention is to build upon the availability of agriculture and abandoned lands bydiversifying bioproduct offerings in Maritime Canada, and taking advantage of port andtransportation infrastructure to access domestic and export markets. Our interests in domesticand export market opportunities include attracting industrial users in food, biofuels, bioplastics,animal feed, and pharmaceutical manufacturing.

Short-rotation woody crops (SRWC) represent a significant potential source of renewablebiomass feedstock and hybrid-willow varieties are considered a high-yield SRWC that mayenable economic development in the agro-forestry and bioproducts sectors of Maritime Canada.As a robust crop, it has been grown on former mine sites as well as underutilized agriculturalfarmland and can be grown on both large- and small-plantations.

There are more than 1 million acres of marginal or underutilized land across Southern Canadaand the Upper Midwest United States (Bouman, 2009). It is estimated that 1,100 hectares ofabandoned farmland is available in Cape Breton and up to 25,000 hectares of farmland isunderutilized throughout Nova Scotia (CBCL, 2008). By making productive use of under-utilizedcropland, hybrid-willow SRWC could generate a source of revenue by supplying a bioproductsmanufacturing market, including bioenergy, and in turn, improve farm finances and stimulateeconomic development in rural regions (Abrahamson, Volk, Smart, & Cameron, 2009)(Abrahamson, Volk, Kopp, White, & Ballard, 2002).

This report provides a guideline to best practice in the production of hybrid-willow SRWC, which may be an alternative cash crop for the agro-forestry sector and used in bioproductdevelopment. This report may aid those considering the establishment of a hybrid-willowplanation with decision-making, design and practice, so they may achieve expected yield andprofitability. Highlights of this report include an overview of SRWC and available hybrid-willowvarieties, guidelines on site selection, plantation design and establishment, and estimates onproduction. The report provides guidance on monitoring and maintenance for the plantations,including weed control, cut back, fertilizer applications, pest and disease control, harvesting, and post-plantation site restoration.

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2 CBU Hybrid-Willow SRWC Demonstration Project

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In June 2010, the Verschuren Centre at Cape Breton University partnered with Enterprise CapeBreton Corporation to research and demonstrate the potential for hybrid-willow to be a value-addedcash crop to the agriculture and forestry sectors of Cape Breton Island. The project aimed to generate knowledge in the development of biomass crops that could be grown on abandoned, underutilized or remediated lands. SRWC silviculture is characterized by high planting density (approximately 13,000-16,000 cuttings per hectare), periodic harvesting over a period of approximately a 25-year lifespan, with mean yields of 10 oven dry tonnes per hectare annually or greater.

Demonstration plantations were established as follows:

• Cape Breton University - former agricultural land• Point Edward Farm - former experimental agricultural land• Broughton - remediated mine site

In 2011 the project was expanded to include a plot at Rendell’s Farm in Point Aconi, Cape Breton, with partners Lockheed Martin Corporation and Rendell’s Farm.

The purpose of the project was to demonstrate the yield of 3 commercial hybrid-willow varieties and experimentally trial 10 hybrid-willow clones. The three commercial hybrid-willow varieties included Viminalis, SX-64, and SX-67. They were planted on all four locations (approximately 0.9-hectare demonstration sites). Twelve varieties, including 10 experimental clones, were planted on a single 0.4-hectare experimental demonstration plot located at Point Edward Farm. The establishing year, planting locations and willow varieties are provided in Table 1. The hybrid willow was sourced from Francis Allard of Agro-Energie in Quebec, Canada.

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Figure 1 - Cape Breton University, October 11, 2011

October 27, 2011

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Table 1 - Hybrid-Willow variety by establishment year and planting location

Year Planting Location Willow Variety

2010 Point Edward Experimental Plot SX-61 Fishcreek Owasco Otisco Eriocephales SV1 Sherburne Canastota Discolor

Broughton, CBU, Point Edward Farm, and Viminalis Point Edward Experimental Plot SX-64

Broughton, CBU, and Point Edward SX-67

2011 Rendell’s Farm Viminalis SX-64 SX-67

Figure 2 - Point Edward Farm

May 30, 2011 July 4, 2011

October 27, 2011 September 14, 2011

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3 Advantages of Hybrid- Willow SRWC

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SRWC are intensive cultures, characterized by high densities, short harvesting cycles, and highpost-harvest stump sprout densities. Hybrid-willow SRWC may be managed within an agricultural-based production system, similar to perennial cropping systems, while making use of a combination of agricultural and forestry practices. “The crop is established from cuttings prepared from one-year-old wood produced by specialist nurseries. The cuttings are inserted into the ground in spring and at the end of the first growing season they are cut to ground level (coppiced) to encourage the development of the multi-stemmed stool. Growth is rapid after cut back and can be as much as 4 metres in the first year increasing to 6-8 metres at harvest in three years (short-rotation) following cutback. A willow coppicing may be harvested 6-8 times on a three-year cycle giving the plantation a life of 19-25 years allowing for the first or establishment year. The coppice can then be removed and the land returned to conventional cropping. Willow (Salix) is a preferred genus for short-rotation woody crops for a number of reasons:

• Native to northern temperate zones, and therefore thrives in the cool wet conditions and largely heavy soil;

• Pioneer species: it is one of the first woody species to colonize disturbed ground;• Easily and quickly establishes from unrooted cuttings (in favourable conditions, roots can be produced

within ten days of planting, which is important in making the cuttings selfsustaining as quickly as possible);

• Vigorous juvenile growth, which enables short harvesting cycles;• Ability to coppice or re-sprout from the stool that remains after harvest, and ability to be coppiced

regularly and repeatedly without losing vigour;• Extensive root system, which enables ability to help maintain and improve soil conditions in barren

fields by reducing erosion, improving nutrient cycling, and in turn, increase soil biodiversity; and• Useful for phytoremediation, riparian buffers, and stream bank restoration. (Abrahamson, Volk, Smart,

& Cameron, 2009) (Caslin, Finnan, & McCracken, 2010)

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4 Hybrid-Willow Varieties, Sourcing and Selection

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The European Breeding Programme in Rothamsted offers commercially available varieties from include: Nimrod; Resolution; Discovery; Endeavour; Beagle; and Terra Nova. European plant breeders’ rights protect these improved commercial varieties. In practice, this means that it is illegal to produce propagation material for self-use or sale from protected varieties. There is a minor derogation, which allows the gapping up of establishing crops with the material produced at cutback. Generally, therefore, cuttings will be produced by specialist growers in nursery beds and supplied as one-year-old rods for mechanical planting. (Caslin, Finnan, & McCracken, 2010).

Svalof Weibull AB, a commercial company operating a breeding program in Sweden since 1987 that was initiated by the Swedish University of Agricultural Services in Uppsala, focuses on Salix viminalis and its hybrids with Salix schwerinii, and can supply the following commercial varieties: Tora; Sven; Torhild; Tordis; Olof; Gudrn; and Inger. (Caslin, Finnan, & McCracken, 2010).

Willow breeding programs are generally focused on advancements in productively and disease resistance.

Hybrid-willow may be sourced from Double A Willow, which will provide stem cuttings of Salix varieties on

behalf of the State University of New York College of Environmental Science and Forestry (SUNY-ESF).

Available hybrid-willow varieties are listed in Table 2, including clones (those with clone IDs), which are a group of genetically identical cuttings that originated from one plant and were developed by Lawrence Smart, Timothy Volk, and Lawrence Abrahamson while at SUNY-ESF. (Abrahamson, Volk, Kopp, White, & Ballard, 2002)

Commercially sourced hybrid-willow planting rods and cuttings are usually produced in irrigated, fertilized nursery cutting orchards that are cut annually during the dormant season, packaged in plastic-lined waxed boxes to prevent moisture loss, and stored at 25 - 30°F. According to Abrahamson, Volk, Kopp, White and Ballard (2002), cuttings should be planted during the spring following their production, and some clone varieties may be stored for a year under the right conditions. According to Caslin, Finnan, and McCracken (2010), “It is absolutely imperative that mixtures of willow genotypes are used when establishing a new plantation” and they suggest maximizing genetic diversity by selecting at least six different genotypes drawn from different breeding programs.

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Table 2 - Available hybrid-willow varieties with commercially available varieties in a white background and development varieties in a grey background (Abrahamson, Volk, Smart, & Cameron, 2009)

Variety Clone ID Species Diversity Group Patent #

SV1 Salix, dasyclados 1S365 Salix caprea hybrid 3S25 Salix eriocephala 4SX61 Salix sachalinensis 2SX64 Salix miyabeana 5SX67 Salix miyabeana 5Fish Creek 9882-34* Salix purpurea 6 PP17,710Onondaga 99113-012 Salix purpurea 6Allegany 99239-015 Salix purpurea 6Sherburne 9871-31 Salix sachalinensis x Salix miyabeana 7Canastota 9970-036 Salix sachalinensis x Salix miyabeana 7 PP17,724Tully Champion 99202-011* Salix viminalis x Salix miyabeana 8 PP17,946Owasco 99207-018* Salix viminalis x Salix miyabeana 8 PP17,845Otisco 99201-007* Salix viminalis x Salix miyabeana 8 PP17,997Oneida 9980-005* Salix purpurea x Salix miyabeana 9 PP17,682Millbrook 99217-015* Salix purpurea x Salix miyabeana 9 PP17,646Fabius 99202-004 Salix viminalis x Salix miyabeanaTruxton 99207-020 Salix viminalis x Salix miyabeanaPreble 01X-268-015 Salix viminalis x (S. sacalinen-sis x S. miyabeana)

Oneonta 9879 Salix purpurea x Salix miyabeanaWolcott 9882-41Cicero 9870-1Marcy 9870-23Saratoga 99217-023Verona 99201-002Talberg 99202-043Erie 99208-038Sunny Twist 99272-016

Furthermore, successful establishment depends on cutting quality to ensure the planting rods or cuttings were prepared from one-year-old lignified wood and do not show any signs of dehydration (discoloration or wrinkling) or inadequate carbohydrate reserve, which are required to sustain the cutting until its roots are established. Selection of planting rod or cutting may depend on the type of mechanical planter to be utilized. The Swedish Step Planter may use planting rods of 1.5-2.5 m length, as the planter will prepare the individual cuttings from each rod. Other specialist planters require prepared cuttings sized for direct planting, which is usually a minimum of 150-mm in length with a minimum diameter of 9-mm. (Caslin, Finnan, & McCracken, 2010)

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5 Site Selection

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While willow grows best on good agricultural soils, it can also be grown successfully on soils that are marginal for traditional crops (see Table 3). According to Caslin, Finnan and McCracken (2010), “Willow is not a demanding species in terms of its site requirements. It will flourish on a wide range of soil types and environmental conditions and in common with other crops productivity will be determined by: site soil fertility; water availability; temperature; access; area; and light.” Soil properties are important for establishing successful plantations of willow biomass crops, with better quality agricultural soils will produce greater yields in early rotations. According to Abrahamson, Volk, Kopp, White and Ballard (2002), willow has been grown successfully on soils ranging in texture from sandy loam to silt to clay loams. Soils with high clay content tend to have low yields in the first rotation although greater yields can result in the second rotation when compared to sandy sites. The pH of the soil is optimal between the range of 5.5 and 8.5. The depth of the soil should be deeper than 45 cm to allow for appropriate rooting and nutrient uptake. See the appendix for an example Soil Test Report from the hybridwillow demonstration project.

Site access design is critical to the long-term management and maintenance of hybrid-willow SRWC plantations, especially as harvesting is carried out in winter in the period (December to April) while a root system of the growing coppice will support the harvesting and extraction equipment on the coppice site. Considerations include field access roads, field slopes, and room to maneuver specialized harvesting machinery. Field slope should not exceed 8% according to SUNY-ESF (2010) and not exceed 13% according to Caslin, Finnan and McCracken (2010).

Water and soil moisture are important considerations for willow growth performance and maneuvering harvesting machinery on field. Annual rainfall between 900 mm and 1,100 mm is idea, as is locating the crop in area with access to ground water. As willow requires a lot of water for growth – more than many other conventional agricultural crops – it requires a good moisture retentive soil, while not being oversaturated. According to Caslin, Finnan and McCracken, “…light sandy soils, particularly in drier areas, may have a problem with moisture availability and highly organic or peaty soils should be avoided, as initial weed control, which is vital, will be extremely difficult. Medium to heavy clay-loams with good aeration and moisture retention are ideal although they must have a capability of allowing a minimum cultivation depth of 200-250 mm to facilitate mechanical planting.” Soil drainage rates will impact growth; although willow can grow on poorly drained sites, it may not be commercially acceptable due to implications for harvesting. Hybrid-willow prefers relatively warm soil conditions for northern temperate zones, and therefore elevated sites may result in exposure problems and a reduction in the number of growing days per year. Caslin, Finnan and McCracken (2010), recommend locating production sites below 100-m above sea level. A relief map of Nova Scotia (Figure 3) Best Practice Guidelines Report Hybrid-Willow Short-Rotation Woody Crops 8 shows the South-shore region, Truro region, Richmond region, Cape Breton Regional Municipality and coastal regions have lands at sub-100 m elevations.

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For commercial, economic and logistical reasons, a minimum planted area commitment of at least 20-ha is recommended, with at least 5-ha blocks to facilitate the large harvesting machinery involved. According to Caslin, Finnan and McCracken, “Smaller and irregular shaped fields are also more difficult to manage and where rabbit fencing is necessary they will be more costly to fence on an area basis.” (Caslin, Finnan, & McCracken, 2010)

Table 3 - Optimal soil conditions for willow growth (Abrahamson, Volk, Kopp, White, & Ballard, 2002)

Consideration Characteristic Suitable Unsuitable

Soil Texture Loams Sandy Sandy loams Course sand and gravel Clay loams Heavy clay with standing water Silt loams Clay Sandy

Structure Well developed to single Massive or lacking structure grain structure

Drainage Imperfectly to moderately Excessively well or very poorly well drained drained (standing water)

pH 5.5 to 8.5 Below 5.5 and above 8.5

Depth 18 inches or more Less than 18 inches

Rainfall, soil Annual rainfall 900 mm to 1,100 mm < 900 mm and > 1,100 mmmoisture and Soil moisturetemperature Elevation < 100 m above sea level > 100 m above sea level

Access Field access Ability to access field with In-ability to access field with planting and harvesting planting and harvesting equipment equipment

Field slope < 8-13%, depending on field > 13% conditions, machinery and equipment

Wet conditions No issue to operating Challenges to operating machinery and equipment, machinery and equipment, and/or low risk of damaging and/or damaging crops/field crops/field

Planted area Plantation block > 2 ha < 2 ha Commercial > 5 ha < 5 ha plantation

Location Transportation If economically justifiable, If not economically justifiable distance and cost depending on market price to market and transportation costs

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Figure 3 - A relief map of Nova Scotia showing elevation by hypsometric tints, (a gradation of different colours), and spot elevations (Natural Resources Canada, 2004)

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Table 4 - Site assessment

Site Name Field Type Issues Tests Treatment

Your Site Name Agricultural Soil fertility Soil fertility Glyphosate application Soil compaction Soil pH Plow and disk Cultivation Fertilizer application Lime application

Fallow Trees Soil fertility Tree clearing Grasses Soil pH Glyphosate application Soil compaction Plow and disk Soil fertility Cultivation Fertilizer application Lime application

Forested Forest removal Soil fertility Forest clearing Soil fertility Soil pH Glyphosate application Soil compaction Plow and disk Cultivation Fertilizer application Lime application

Remediated Trees Soil fertility Tree clearing Grasses Soil pH Glyphosate application Soil fertility Plow and disk Soil compaction Cultivation Fertilizer application Lime application

Abandoned Trees Soil fertility Tree clearing Grasses Soil pH Glyphosate application Soil fertility Plow and disk Soil compaction Cultivation Fertilizer application Lime application

Point Edward Fallow: former Grasses Plow Farm agricultural Herbicide Cultivate Fertilizer

Cape Breton Fallow: former Grasses PlowUniversity Farm agricultural Herbicide Cultivate Fertilizer

Broughton Remediated Soil fertility Compost Cultivate

Rendell’s Farm Agricultural None Cultivate

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6 Plantation Design

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According to Abrahamson, Volk, Kopp, White and Ballard (2002), “The planting design for each field should be carefully thought out before planting begins… [as] willow biomass crops will be productive for about 22 years, so mistakes in the planting design could cause problems for many years.” Hybrid-willow SRWC plantations consist of planting genetically improved willow clones as unrooted hardwood cuttings at densities of up to 15,000 plants per hectare. Commercially, planting is accomplished with mechanized planters specifically designed to use dormant rods or cuttings.

Rows should be designed as long as possible, running across slopes to reduce soil erosion, and with adequate spacing to operate harvesting machines. At least 20-feet should be left at row ends to allow turn-around space for harvesting equipment and for access with other farm equipment, and very long rows should have a 20-foot break inserted every 500-600 feet to allow harvesting equipment to be moved on and off the field.

Willow cuttings can be planted single-row design with up to 1.8-m between rows and 30-cm between plants within rows. To facilitate the management of the site with farm machinery, willow cuttings can be planted in a double-row design (see Figure 4) with 1.5-m between double-rows, 0.75-m between rows, and 60-cm between plants within rows. Preferable to planting a single variety of willow over a large area, willow varieties may be arranged in random blocks that are a few double-rows to several acres in size. In any one field (8 hectares or more), four to six genetically diverse varieties should be planted in random blocks to maximize chances for success and minimize risk from disease and pests. (Abrahamson, Volk, Kopp, White, & Ballard, 2002) (Abrahamson, Volk, Smart, & Cameron, 2009)

Figure 4 - Optional double-row plot design dimensions for cultivating hybrid-willow (Abrahamson, Volk, Kopp, White, & Ballard, 2002)

Also important is to match plantation design, or multiple plantations, to the market demand. Forexample, according to Caslin, Finnan and McCracken (2010), “A 1% uptake in a catchment areawith a 20-km radius (optimal delivery distance for coppice chip to a conversion plant) wouldprovide 1,200 ha or 15,000 tonnes of dry matter, sufficient for 2 MW continuous generation.”

2.5 ft

5 ft

2 ft

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7 Establishment

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Site Preparation

“Since willow will be in the ground for a minimum of twenty-five years,” says Caslin, Finnan and McCracken (2010), “thorough site preparation is essential.” If the land was in an annual agricultural crop the year before, apply a herbicide if necessary, and then plow and disk just before planting in the spring (Abrahamson, Volk, Smart, & Cameron, 2009). On a fallow hayfield, begin site preparation the summer before planting hybrid-willow, preferably during mid- to late July, by baling the hay and mowing the site, and then applying herbicide, plowing and disking the land. Greater detail is provided below.

Pre-plowing Herbicide Application

Where sites have excessively heavy vegetation, the vegetation should be removed to allow for effective weed control. An application of herbicide is recommended. Apply the herbicide prior to plowing and when weeds are still actively growing. Allow sufficient time for re-growth to occur to ensure active herbicide uptake.

Herbicide treatment allows hybrid-willow cuttings a brief head start against weeds and grasses that could overcome the cuttings and significantly increase tree mortality. To give the cuttings the best chance to grow, planted areas should receive competition control or herbicide application prior to plowing a proposed plantation site. A minimum of ten days after herbicide application is required before the site can be plowed.

Glyphosate - a broad-spectrum, postemergent, trans-located herbicide - is recommended as herbicide treatment for hybrid-willow plantation areas. Apply Glyphosate for perennial weed control after the vegetation resumes growth and wait at least two to four weeks to allow the herbicide to work effectively. (Abrahamson, Volk, Kopp, White, & Ballard, 2002)

Herbicide impacts on biodiversity were the focus of a scientific review in 2004 by the US Wildlife Society, and published in the Wildlife Society Bulletin, which found that most studies have indicated that herbicide treatments do not result in broad-scale reductions in plant or animal species richness or animal populations (Lautenschlager & Sullivan, 2004). Safety reviews of Glyphosate by the US Environmental Protection Agency, the Canadian Pesticide Management Regulatory Agency (PMRA), the Canadian Wildlife Service, the Commission of the European Union, the Food & Agricultural Organization of the United Nations, and the World Health Organization have concluded that glyphosate has low toxicity to non-target organisms including humans and does not accumulate in soils or the food chain. (J.D. Irving, Limited, 2012)

Recommendation• Herbicide: Glyphosate

• Application rate: 4-5 litres per hectare

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Glyphosate is registered with PMRA for use as a forestry herbicide and other purposes, such as in the production of food crops and residential home and garden use. PMRA regularly reviews scientific literature on registered pesticides and can be reached at 613-736-3500. (Nova Scotia Environment and Labour, 2007)

In Nova Scotia, the forestry application of herbicides falls under the jurisdiction of Nova ScotiaEnvironment and Labour (NSEL). The department requires compliance with the PMRA registeredlabel and also imposes conditions of its own. The department’s requirements for the forestry use of glyphosate include:

• Formal application for permission• Application of the herbicide to a specified spray zone• Buffer zones around watercourses and wells• Proper weather conditions for drift control• In recognition of the right to know, there must be notification of residents and businesses within

500 metres of the spray area at least 30 days before spraying (this is the notification zone only - not a danger zone)

• Signs advising of the spraying must be posted on access roads to the area 30 days in advance;• The company applying the product must be certified by NSEL• The person applying the product must pass an examination and be certified by NSEL• NSEL must be notified when spraying is about to take place. (Nova Scotia Environment and

Labour, 2007)

In addition, NSEL can require special conditions where circumstances warrant. Glyphosate has been determined by the PMRA to be safe when used as directed on the product label and presents a low risk. These conditions imposed on its use are effective management of that risk. Best Practice Guidelines Report Hybrid-Willow Short-Rotation Woody Crops 14 Ground-spray applicators are required to flag the spray boundaries and ensure the spray lands within them. Both ground and aerial applicators are required to notify NSEL before they start work on an approved area. NSEL inspectors can and do arrive at approved sites at any time to monitor the spraying and applicators are aware of that. Misapplication is obvious from the effect on vegetation. Penalties can include loss of certification and fines of up to $1 million. (Nova Scotia Environment and Labour, 2007]

Under the Activities Designation Regulations, approvals are required for any treatments by air, to water, or to apply pesticides in the following areas: on forested lands; on utility corridors or rights-of-way; roads, streets or highways; and industrial sites for soil sterilization. Under the Pesticide Regulations, an approval is also required to construct a new pesticide storage facility or extend/modify an existing pesticide storage facility to store commercial or restricted class pesticides for sale, resale, or wholesale distribution. Commercial class pesticides are intended for use in agriculture, forestry, industry and other commercial operations. Applicators of commercial pesticides need knowledge on safe handling procedures and require personal protective equipment.

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To apply a commercial or restricted class pesticide in Nova Scotia, the applicator must hold a valid applicators certificate of qualification from the Department of Environment and Labour. For more information, please contact the Regional Office for the Eastern Region of Nova Scotia (inclusive of Cape Breton Regional Municipality, Richmond County, Inverness County, and Victoria County) at 902-563-2100. (Nova Scotia Environment and Labour, 2014)

Cover Cropping

On soils with significant erosion potential, plant a cover crop. A cover crop is a crop that can provide ground cover late in the growing season and is easily killed the following spring, such as Fall (Winter) Rye. According to Wallace and Scott (2008), cover crops can compete with weeds for light, water and nutrients, suppress weeds by allelopathy, and help weed control by improving soil structure, drainage and nutrient release. The ideal cover crops for weed suppression become established quickly, grow rapidly, cover the ground completely and are allelopathic (i.e. a plant that produces compounds that inhibit germination of other plants). Several cover crops are allelopathic, including Fall Rye. (Wallace & Scott, 2008)

In early- to mid-September, plow the field to a depth of 25 cm or more, and then cross disk. Plant the cover crop and allow over-wintering. The following spring, kill the cover crop by applying Glyphosate.

Plowing

On suitable soils, the site can be plowed and power harrowed to prepare a stale seedbed in mid-March, approximately six (6) weeks before planting. Use a cultimulcher (a machine that has rollers both front and rear and 15 cm teeth in the centre) to kill any germinating weeds and loosen the soil for planting, enabling good soil-to-cutting contact without clumps of soil. Prior to planting, any germinated weeds can be sprayed with herbicide using Glyphosate (application rate of 2 litres per hectare). Note, on heavy clay soils, the site should be power harrowed as close to planting as possible. (Abrahamson, Volk, Kopp, White, & Ballard, 2002)

Land that has been regularly and intensively grazed can suffer from compaction close to the surface. Remediated, brownfield lands are also likely to suffer from compaction of soil (or fill). To address this issue, deep plowing and/or sub-soiling is required to allow full root development. Whatever the site, a minimum plow depth of 20-25 cm is required to allow for the insertion of the cuttings. Plowing of land should be achieved in the Fall season in preparation of planting the following Spring. (Agro Énergie, 2010]

In the week prior to planting, use 3-4 days of sunny weather to prepare the land for planting by working the soil to a minimum 15 cm depth of fine soil texture to allow good contact between cuttings and soil, and removing any large rocks or stones that may interfere with the use of mechanical planter prior to planting. In sandy soil, the primary and finish tillage can be accomplished using a standard cultivator. Clay soils, or old prairie, will require primary tillage with a disc cultivator and finish tillage with a power harrows. (Agro Énergie, 2010)

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According to Abrahamson, Volk, Smart and Cameron (2009), “Rocky or stony fields are not a big problem if the rocks are small and the field is not solid rocks.” However, rocks or stones that protrude more than approximately 50 cm above the soil surface should be removed to avoid damage to harvesting equipment or saw blades. (Abrahamson, Volk, Kopp, White, & Ballard, 2002)

Plantation Design

Current commercial practice is to plant 18,000 cuttings per hectare. Establishment survival rate should in excess of 90% in good conditions, and together with a natural loss of stools in the early rotation, should produce a cropping density of 15,000 per hectare (or 83% survival rate). To facilitate mechanical harvesting and machinery access, hybrid-willow may be planted in double rows 0.75-m apart with the double rows spaced at 1.5-m. An in-row spacing of 0.6-m gives an initial planting density of approximately 18,000 per hectare. Other plantation design considerations include: • Where possible, plant rows in parallel to the longest axis of the field to maximize planter and harvester

machine efficiencies• Avoid running rows across steep slopes• Plan headlands to have ground structure that allow for the carrying capacity and turning space required

for planting and harvesting machinery, as unplanted headlands that become compromised in prevailing climatic conditions.

Planting

Hybrid-willow planting material consists of either unrooted, dormant stem cuttings 15-cm to 25-cm in length and 1-cm to 2-cm in diameter or dormant stem whips from 120-cm to 215-cm in length and 1-cm to 2-cm in diameter. These limits are based on planting machine design and storage box length. Hybrid-willow cuttings should be procured from a supplier that harvests in winter, when the buds are fully dormant, and maintained in refrigerated storage at -2°C and -4°C and wrapped in polythene film to protect against dehydration up to the point of planting.

Site preparation may begin in early spring – April through May – when weather conditions allow. Ideally, planting would take place in late April to late May, but it can be completed as late as mid June if necessary. Early May planting is advisable so that soil moisture is sufficient to support root development. According to Caslin, Finnan and McCracken (2010), “Early planting will give early establishment and a longer growing season for the establishing crop with a lower risk of water stress from a late spring dry period.”

Cuttings will produce both roots and shoots after planting. Shoots typically sprout within two weeks after planting, with best growth in warm temperatures and moist, but not saturated soils. Meanwhile, low soil and air temperatures will slow sprouting and growth. At the extreme, early planting increases the chance of frost damage to young, recently sprouted cuttings, while late planting (June) is risky because soil moisture may become limiting for root development. If willow cuttings do not establish good root systems during the first growing season, they are prone to frost heave during their first winter. (Abrahamson, Volk, Kopp, White, & Ballard, 2002)

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All commercial planting is accomplished using mechanical planters. Several types of mechanical planters have been used but the dedicated Step Planter designed in Sweden by Salix Maskiner has become the industry standard. This planter plants two double rows at a pass and automatically makes the cuttings from rods inserted into the planting heads. In ideal conditions, it has a capacity of 6-8 ha per day. However, in the smaller field sizes that are likely to be encountered, this cold be reduced to 4-5 ha per day. (Agro Énergie, 2010)

Common willow planting machines include:

• Fröebbesta planter, which plants hybrid-willow cuttings• Egedal Energy planter (see Figure 5)• Salix Maskiner’s Step planter (see Figure 6 and Figure 7), which plants hybrid-willow whips or rods

Figure 5 - Egedal Energy planter (Egedal Maskinfabrik A/S, 2014)

According to Abrahamson, Volk, Kopp, White and Ballard (2009), “The Step and Egedal willow planters increases the efficiency of planting willow biomass crops compared to the Fröebbesta planter in a number of ways. The use of whips versus cuttings as planting stock results in savings in the cost of planting material production since labour is not required to make the whips into cuttings. The Step and Egedal planter’s plant two double-rows (four rows) at once, while the current Fröebbesta machine only plants one double-row (two rows) at a time. The Step planter is best operated with a four-person crew managing the feeding of whips into the planting mechanism. With experience, the crew may be reduced to two (plus a tractor driver). The Egedal planter requires a two-person crew plus the tractor driver.

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Since two people are required to operate all three planters, the man-hour requirement for planting a given field is cut in half with the Step and Egedal Energy planters. Both the Step and Egedal planters require a tractor with at least 140 [horsepower] and sufficient weight to handle either the 3,500-lb Step planter or the 6,000-lb Egedal Energy planter on its 3-point hitch. The Step and Egedal planter’s output is about two acres per hour, while to Fröebbesta planter’s output is half an acre per hour. The Fröebbesta is a smaller machine that is easier to operate with a smaller tractor, so it will still be used for planting smaller parcels of land and specialized willow plantings such as riparian buffers.

Figure 6 - Salix Maskiner’s Step planter (IGGESUND Holmen Group, 2013)

Figure 7 - Salix Maskiner’s Step planter (SUNY-ESF, 2004)

Commercial willow planters have successfully used the Egedal Energy Planter, which is designed and built in Denmark. Compared to the Step planter, the Egedal Energy Planter uses willow whips that may be more curved, bigger in diameter, and with more cut branch ends. According to Abrahamson, Volk, Smart and Cameron (2009), “The disadvantage of the Egedal is that it does not place the cuttings in the ground as straight as the Step planter and in wet heavy clay soils may have trouble closing the planting slit with the cuttings in them.”

Hand planting is only recommended for experimental and pilot projects on lands less than 2 hectares.

After planting, the site should be rolled to consolidate the surface and provide the best possibleconditions for the application of residual herbicides to be effective.

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8 Schedule and Production Timeline

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Event Responsibility Date Planned Date Executed

Last year crop

Plow

Land preparation

Cuttings storage planification

Plantation

Herbicide purchase

Spraying

Is your sprayer in good condition?

Do you have a sprayer chart?

Inter-row cultivator purchase

Weed control follow up

Inter-row cultivator 1st pass

Inter-row cultivator 2nd pass

Inter-row cultivator 3rd pass

Cut back

Table 5 - Schedule of work and timelines

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Figure 8 - Typical hybrid-willow production and maintenance timelines (Abrahamson, Volk, Kopp, White, & Ballard, 2002)

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9 Monitoring, Maintenance and Management

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Crop monitoring, maintenance and management in the establishment year (post-planting up to cutback, and after leaf fall in the early winter), according to Caslin, Finnan and McCracken (2010), “is crucially important, particularly in terms of weed control. This cannot be over emphasized, as newly planted willow cannot effectively complete against most weeds. If adequate weed control is not achieved, then a successful coppice system will not be established.”

Weed management is recommended during the establishment year and from April to the end of July in the first growing season, or as necessary. During the establishment year and the first growing season, weeds tend to be a challenge to manage due to a lack of canopy formation. However, once the canopy forms in the second growing season, the willow will out-compete weeds for available sunlight. Willow plantations should be monitored weekly during the establishment year and first growing season. Regular monitoring should include weed identification and assessment, enabling timely plantation maintenance and weed management.

Mechanical weed management is required in the establishment year and first growing season. An inter-row cultivator may be used to mechanically address weeds between each row; however, weeds between plants are harder to manage. Agro Énergie (2010) recommends driving an inter-row cultivator at a minimum speed to 9 km/h in order to displace soil over the weeds between the willow plants, thereby burying most of the emerging weeds. Usually, two or three inter-row cultivator passes will be necessary in the establishment year. Further, cultivators and rototillers designed to accommodate the double-row spacing used in willow plantings have been developed (see Figure 9).

According to SUNY-ESF (2010), “If problematic perennial weeds such as crown vetch, morning glory, or thistle are present, a mixture of herbicides is more appropriate for application.” Although contact herbicide application with shielded sprayers has been used successfully, willows are highly sensitive to post-emergent herbicides, so the risk of damage is high. Caution is advised when using herbicide once the willow has become established.

If fertilization is considered during the first growing season, Abrahamson, Volk, Kopp, White and Ballard (2002) recommend removing the weeds prior to fertilization, as otherwise, fertilized weeds may overtop trees. “It is better not to fertilize,” argue Abrahamson, Volk, Smart and Cameron (2009), “if weeds are a problem and they cannot be satisfactorily controlled. In this case, fertilization can occur at the start of the second rotation.”

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Figure 9 - A multi-row rototiller used for weeding in the first growing season (Abrahamson, Volk, Kopp, White, & Ballard, 2002)

Weed management can be separated into four phases: pre-plowing; post-planting; establishment year; and first growing season. For guidelines on weed management, please see Table 6.

Grasses can be a challenge for the establishment of hybrid-willow, especially with improper site preparation, as they compete for light and nutrients. According to Abrahamson, Volk, Kopp,Best Practice

White and Cameron (2009), “Grasses can be effectively managed with grass post-emergentherbicides, such as Fusillade, sprayed over the top of the willow plants.”

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Phase Weed Management Description

Pre-plowing Apply a translocated herbicide (e.g., Glyphosate at 3-5 l/ha) to actively growing vegetation in early autumn, before plowing in the spring.

• If necessary, re-apply a translocated herbicide just prior to plowing, leaving a period of ten days post-application before plowing.

Post-planting Apply a pre-emergent residual herbicide: • Recommend a mixture of pendimethalin and Isoxaben (e.g. Flexidor at 1 l/ha); • Include an insecticide, such as chlorphrifos (e.g. Dursban at 3 l/ha), to control

leatherjackets – the larval stage of the Cranefly or ‘Dandylong-legs’ (Tipula); • High volume (500 l/ha) applications should be used to give good surface coverage

of the herbicide and adequate penetration of the insecticide; and • Apply within fourteen days after planting.

Establishment year If necessary, over-spray the plantation with contact herbicide. There is a limited range of contact herbicides available for over-spraying the established willow, and they are highly specific herbicides with a limited weed spectrum. Options include:

• Thistle control: Clopyralid (e.g. Dow Shield at 0.5-1 l/ha) • Grass control:

- Fluazifop-p-butyl (e.g. Fusilade at 1.5 l/ha); - Cycloxidim (e.g. Laser at 2.5 l/ha); or - Propaquizafop (e.g. Falcon 1.4 l/ha).

• Directed spraying using an inter-row guarded sprayer: Paraquat (e.g. Gramoxone at 3 l/ha) - Note: willow is highly susceptible to the herbicides used

• Perennial weeds, like docks and nettles, may be spot treated using guarded knapsack sprayers and appropriate herbicide.

Mechanical weed management using inter-row cultivators is an option. • Caution: effective weed management using an inter-row cultivator may risk

willow damage, either from risk of willow dehydration due to disturbed weed cover or direct mechanical disturbance damage.

First growing season In mid-summer of the first growing season, apply herbicide to keep the crop weed-free until it achieves canopy closure

• Recommend a mixture of amitrole (e.g. Weedazol at 10-20 l/ha) and pendimethalin (e.g. Stomp at 3.3 l/ha)

Mechanical weed management using inter-row cultivators is an option. • Caution: effective weed management using an inter-row cultivator may risk

willow damage, either from risk of willow dehydration due to disturbed weed cover or direct mechanical disturbance damage.

Table 6 - Weed management guidelines (Agro Énergie, 2010)

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Cut Back

Growth during the establishment year will vary, usually from 1 m to 2.5 m in height, with one to four stems per plant. To promote multiple sprout formation (8 to 10) and rapid canopy closure in the first growing season, at the end of the establishment year, the hybrid-willow may be cut back (coppiced) at a height of 2 cm using a sickle bar mower or rotary mower (see Figure 10). Ensure the blade is sharp and forward speed is such that the willow is cut cleanly, without tearing and/or pulling the roots out of the soil. This should occur around the middle of November, although it could occur anytime between two weeks after leaf fall and when buds begin to swell in spring (typically early March). (Abrahamson, Volk, Kopp, White, & Ballard, 2002)

According to Abrahamson, Volk, Smart and Cameron (2009), “Under severe weed conditions, where good weed control does not seem possible, coppicing of the first-year plants should not be done so the willow plants can stay above the weeds… and be able to compete for light. Under these conditions, this may be the only way this crop will survive with a high enough density to be profitable. If the weeds get over the top of the willow, they will not survive.” (Abrahamson, Volk, Smart, & Cameron, 2009)

Figure 10 - Sickle bar mower (left) and rotary mower (right)

Following cutback, the coppice enters its cropping cycle of between two and four years. At harvest, the coppice will have attained a maximum height of 7 m to 8 m. According to Caslin, Finnan and McCracken (2010), “only the most vigorous of the shoots produced at cutback will survive to this point, the weaker ones having been shaded out.” (Caslin, Finnan, & McCracken, 2010)

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Fertilizer Application

From an economic perspective, fertilizer should be used sparingly when growing willow SRWC. Fertilizer application depends on site fertility and should only be applied as the result of formal soil analysis and the consideration of other inputs in perennial crops such as internal recycling of nutrients in the leaf litter. Fertilizer application is not recommended on most sites in the first growing season. According to Caslin, Finnan and McCracken (2010), “…in the absence of any long-term direct information of fertilizer and yield, nutrient off-take in the harvested crop should be used in calculating fertilizer requirement.” They continue to say, “Published nutrient off-take figures for the harvested crop vary but are in the range; 150 – 400 kg N, 180 – 250 kg K, and 24 – 48 kg P per hectare per three-year rotation based on an 8 – 10 t DM/ha/yr crop.” Furthermore, “…as a guide, to be confirmed with soil analysis and expected yield,” say Caslin nutrient application should not exceed the equivalent of 120-150 kg nitrogen, 15 – 40 kg phosphorus, and 40 kg potassium per hectare per year.” (Caslin, Finnan, & McCracken, 2010)

In June 2011, the Point Edward, CBU and Broughton willow plantations (2.8 hectares total) were fertilized (post cutback) with 120-kg of nitrogen per hectare. The plantations required 1,158.6-kg of N-P-K fertilizer, which was procured in 500-kg super-sacks from Cavendish Farms with the following specifications: Nitrogen (N): 29%; Phosphorous (P): 5%; and Potassium (K): 5%. It was shipped via refrigerated transport trucks from Prince Edward Island to Cape Breton Island.

Except for the summer following harvesting, fertilization during the growing seasons is not required, and the size and density of the willow makes fertilizing plantations impractical. According to Abrahamson, Volk, Kopp, White and Ballard (2002), “During the third and fourth growing seasons (second and third seasons after coppicing), no tending of the crop should be necessary.”

Deer Browsing

Deer browsing was observed in the establishment of the hybrid-willow SRWC plantations, with preference observed for the soft tips of the willow prior to gaining a hard, woody texture. Following the establishment year, deer browsing decreased as the willow became taller and woody. Overall, deer browsing is unlikely to be significant enough to affect the 3-year harvest yield of hybrid-willow SRWC. If deer appears to be a challenge for willow establishment, browsing control is limited, with the cost of fencing to exclude deer is prohibitively expensive. According to Abrahamson, Volk, Smart and Cameron (2009), “Commercial plantings established in areas with high deer pressure will have to use designs that can minimize browsing by using clones that are unpalatable to deer, such as Fish Creek, near the edges of deer habitat.”

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Pests Common to Willow

According to Abrahamson, Volk, Kopp, White and Ballard (2002), “Insects generally have not been a problem in experimental willow plantings in New York. Limited foliage feeding by insects is commonly observed, but impacts are not considered severe enough to warrant insecticide application.” For your information, please find a listing of the commonly observed pests and their impacts on willow in Table 7. Figure 11 provides pictures of insects and a bird nest observed during the hybrid-willow demonstration project.

Table 7 - Pests commonly observed on willow

Pest Issues

Various midges (Dasyneura sp.) * Death of terminal bud or rolling of the leaf margins

Various aphid species * Damage to above ground biomass yields and root • Giant willow aphid systems• Black willow aphid

Willow beetles: Foliage feeding, damage and defoliation• Phratora vitellinae (brassy/green) *• Phratora vulgatissima (blue) *• Galerucella lineola (brown) *• Japanese beetle (Papillia japonica) **• Imported willow leaf beetle (Plagiodera versicolora) **• Calligraphia beetle **

Potato leafhopper *** Damage to leaves (i.e. “hopperburn” which includes yellowing, stunting and curling)

Gypsy moth larvae (Lymantria dispar) ** Foliage feeding and loss

Forest tent caterpillar (Malacosoma disstria) ** Foliage feeding and loss

Willow sawflies (Nematus ventralis) caterpillars ** Foliage feeding

Willow shoot sawflies (Janus abbreviatus) ** Foliage feeding

* (Caslin, Finnan, & McCracken, 2010)

** (Abrahamson, Volk, Kopp, White, & Ballard, 2002)

*** (Abrahamson, Volk, Smart, & Cameron, 2009)

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Figure 11 - Pictures of insects and birds nest observed during the hybrid-willow demonstration project

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10 Harvesting

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10 HarvestingHybrid-willow should be ready for first harvest during the winter – between leaf fall and bud swell in early spring – three years after the first coppice, or four years after planting. In Cape Breton Island, it is recommended that harvesting occur in late October or early November. Following the first harvest, hybrid willow may continue to be harvested on a three-year cycle for 20-25 years before replanting. (Abrahamson, Volk, Kopp, White, & Ballard, 2002).

Cut the hybrid-willow at approximately 10-cm from the ground using harvesting equipment that has been developed specifically for hybrid willow biomass plantations. There are three approaches to harvesting:

• Direct chip harvesting, using a willow forage harvester (a modified corn harvester with two large saw blades and chipper) or a ‘Bender’ harvester (a single, long chain-saw and chipper) presented in Figure 12.

• Whole rod harvesting, which will dry over time to approximately 30% without deterioration when naturally ventilated, and therefore do not require drying facilities.

• Billeting, which produces cuttings 5-10 cm in length that may be used for planting.• Bailing, which includes the Anderson Group Co.’s BiobalerTM that cuts and compacts biomass

into a dense round bale in a single pass, with only one operator (for more information, visit http://grpanderson.com/en/biomass/biobaler-system).

Willow chips or billets may be blown from the harvester into large self-unloading forage wagons pulled by tractors. While chipping allows for less handling and more efficient transport, whole stems bundles can be stored longer without deterioration. According to Abrahamson, Volk, Smart and Cameron (2009), harvest rates vary from 45 to 55 wet tonnes per hour (approximately 0.8 hectares per hour). According to Caslin, Finnan and McCracken (2010), “Questions regarding damage to willow stools still need to be addressed and fully researched to ensure the biobaler is not damaging crops.”

Figure 12 - Willow forage harvester and bender harvester (Abrahamson, Volk, Kopp, White, & Ballard, 2002)

Figure 13 - Broughton site pre-harvest, Fall 2013

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Figure 14 - CBU willow post harvest

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11 Yield

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According to Caslin, Finnan and McCracken (2010), it has been estimated that the above ground woody stems of hybrid-willow represents 60% of the total biological yield, with 10% allocated to the leaves of 30% to the root system. Sustainable yields of 10 to 12 oven-dry tonnes per hectare per year (odt/ha/year) can be achieved based on good soil fertility, light exposure, or water availability. According to Abrahamson, Volk, Smart and Cameron (2009), hybrid-willow yields may be expected to be 30 oven-dried tonnes per hectare per year (odt/ha/year) in the first three years of fertilized and irrigated willow grown for three years, 10 to 12 odt/ha/year during the first rotation and 13.5 to 18 odt/ha/year during the second rotation. Yields may vary depending on site and weather conditions, among other factors, that normally determine yield from conventional crops. According to Caslin, Finnan and McCracken (2010), “short rotation coppice willow dry mater has energy content of approximately 18 MJ per kg.”

The yield results of Cape Breton University’s hybrid-willow demonstration project are presented in Figure 15 and Figure 16. Overall, growth on the Broughton remediated mine site surpassed growth on former agricultural lands. The SX-64 and SX-67 varieties of hybrid willow outperformed Viminales, which was both observationally recognizable and confirmed in our harvest data. In the experimental trial, Fabius was the top performer at 22.1 odt/ha/year. Further trials of Fabius would be valuable to determine its commercial viability, along with SX-61 (16.8 odt/ha/year), Otisco (15.4 odt/ha/year), SV1 (13.5 odt/ha/year), and Sherburne (13.3 odt/ha/year).

Figure 15 – Hybrid-willow yield (tonnes per hectare) by trial location and variety, Cape Breton Island

Figure 16 – Hybrid-willow yield (tonnes per hectare) by experimental trial variety

Hybrid-Willow Varieties

Willow Varieties

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Location Hybrid- Plot No. of Avg. Plant Predicted Total Yield, Annual Avg. Moisture Annual Dry Willow Size (ha) Cuttings Yield (kg) Yield* Wet Yield, Wet Content (%) Yield Variety (kg/plot) (tonnes/ha) (tonnes/ha) (Oven-dried tonnes/ha)

Point Fabius 0.024 500 7.075 3183.750 132.656 44.2 50.0 ** 22.1

Edward SV1 0.024 500 4.325 1946.250 81.094 27.0 50.0 ** 13.5

Experimental Otisco 0.024 500 4.925 2216.250 92.344 30.8 50.0 ** 15.4

Canostota 0.024 500 3.700 1665.000 69.375 23.1 50.0 ** 11.6

Fishcreek 0.024 500 3.575 1608.750 67.031 22.3 50.0 ** 11.2

Viminales 0.024 500 3.525 1586.250 66.094 22.0 50.0 ** 11.0

Owasco 0.024 500 3.225 1451.250 60.469 20.2 50.0 ** 10.1

Sherburne 0.024 500 4.25 1912.50 79.688 26.6 50.0 ** 13.3

SX61 0.024 500 5.375 2418.750 100.781 33.6 50.0 ** 16.8

SX64 0.024 500 4.567 2055.000 85.625 28.5 50.0 ** 14.3

Eriocephales 0.024 500 0.600 270.000 11.250 3.75 50.0 ** 1.9

Discolor 0.024 500 1.050 472.500 19.688 6.56 50.0 ** 3.3

Broughton SX67 0.160 2475 4.290 9555.975 59.725 19.9 50.3 9.9

Viminales 0.160 2475 1.900 4232.250 26.452 8.8 56.2 3.9

SX64 0.160 2475 4.100 9132.750 57.080 19.0 49.3 9.6

CBU SX67 0.230 3733 3.000 10079.100 43.822 14.6 47.0 7.7

Viminales 0.230 3733 1.300 4367.610 18.990 6.3 54.0 2.9

SX64 0.230 3733 2.700 9071.190 39.440 13.1 47.9 6.8

Point Edward SX67 0.230 3733 3.563 11970.611 52.046 17.3 48.6 8.9

Viminales 0.230 3733 1.975 6635.408 28.850 9.6 54.5 4.4

SX64 0.230 3733 1.903 6393.509 27.798 9.3 46.6 5.0

Table 8 – Hybrid-willow demonstration project yield results

* Note: Predicted yield at 90% survival rate of willow cuttings and an average plant size (kg) determined from a cross-sectional sub- sampling of the plots.

** Assumed moisture content

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12 Conclusions

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The yield results of Cape Breton University’s hybrid-willow demonstration project are presented in Figure 15 and Figure 16. Overall, growth on the Broughton remediated mine site surpassed growth on former agricultural lands. The SX-64 and SX-67 varieties of hybrid willow outperformed Viminales, which was both observationally recognizable and confirmed in our harvest data. In the experimental trial, Fabius was the top performer at 22.1 odt/ha/year. Further trials of Fabius would be valuable to determine its commercial viability, along with SX-61 (16.8 odt/ha/year), Otisco (15.4 odt/ha/year), SV1 (13.5 odt/ha/year), and Sherburne (13.3 odt/ha/year).

This report demonstrates that hybrid-willow can perform very similar in different planting conditions. Remediated sites can yield as much as agricultural lands within the first establishment years of the crop. However, further study into the coming years and subsequent harvest rotations are required to determine if this trend will prevail over the willow’s lifecycle.

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13 ReferencesAbrahamson, L. P., Volk, T. A., Kopp, R., White, E., & Ballard, J. (2002, January). Willow Biomass Producer Handbook. Retrieved March 2014, from Agro Energie: http://agroenergie.ca/pdf/Culture_du_saule/Willow_biomass_producer_handbook.pdf

Abrahamson, L. P., Volk, T. A., Smart, L. B., & Cameron, K. D. (2009). Shrub Willow Biomass Producer’s Handbook. State University of New York, College of Environmental Science and Forestry. Syracuse: SUNY-ESF.

Agro Énergie. (2010). Willow Establishment Year “Step by Step” Procedure. Agro Énergie. Caslin, B., Finnan, J., & McCracken, A. (2010, September). Short Rotation Coppice Willow Best Practice Guidelines. Retrieved March 2014, from Agro Energie: http://agroenergie.ca/pdf/Culture_du_saule/SRWC_Best_Practices_Guidelines.pdf

Egedal Maskinfabrik A/S. (2014). Egedal Energy Planter. Retrieved August 2014, from Egedal Maskinfabrik A/S: http://www.egedal.dk/export/sites/default/billeder/produkter-store/ Energy_1_stor.jpg

IGGESUND Holmen Group. (2013). Preperations are essential. Retrieved August 2014, from http://biofuel.iggesund.co.uk/preperations-are-essential-2/

J.D. Irving, Limited. (2012). Growing the Future Forest and Responsible Herbicide Use. Retrieved August 2014, from https://www.jdirving.com/uploadedFiles/White_Papers_and_ Publications/JDI%20Irving%20Woodlands%20%20-%20Responsible%20Herbicide%20Use.pdf

Lautenschlager, R., & Sullivan, T. (2004, December). Improving research into effects of forest herbicide use on biota in northern ecosystems. Wildlife Society Bulletin , 32 (4), pp. 1061-1070.

Natural Resources Canada. (2004). Nova Scotia Relief. Retrieved 2014, from Natural Resource Canada: http://atlas.gc.ca/site/english/maps/reference/provincesterritoriesrelief/ns_relief

Nova Scotia Environment and Labour. (2007, July). Media Backgrounder Herbicide Management. Retrieved August 2014, from http://www.novascotia.ca/nse/pests/docsHerbicideBackgrounder.pdf

Nova Scotia Environment and Labour. (2014). You Asked About... Pesticides. Retrieved August 2014, from http://www.novascotia.ca/nse/pests/docs/YouAskedAboutPesticides.pdf

SUNY-ESF. (2004). The Willow Biomass Program. Retrieved August 2014, from Willow / Woody Biomass at ESF: http://www.esf.edu/willow/

Wallace, J., & Scott, J. (2008). Under Cover - A Guide to Using Cover Crops in the Maritimes. Retrieved August 2014, from http://nsfa-fane.ca/wp-content/uploads/2011/06/UnderCover2008.pdf

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AppendixNova Scotia Agriculture Soil Test Report

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Verschuren CentreCape Breton University

P.O. Box 5300, 1250 Grand Lake RoadSydney, Nova Scotia, Canada B1P 6L2

www.verschurencentre.ca


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