CHCx3 Willow Variety Guide
Planting Short Rotation Coppice (SRC) willow is a long-term venture as the crop is expected to be in the ground for over 20 years. It is really important to make sure that a farmer makes the right choice of varieties for their land, their soils, their climate and their market.
As part of the CHCx3 project we are producing a Willow Variety Guide. This will provide bang up to date information on yields and research outputs.
The Need for Independent Variety Evaluation
A notable feature of the UK farming sector is the widespread use of independently generated Recommended Lists for major crops, including cereals, oilseeds, pulses and grasses. UK farmers are accustomed to making variety selection decisions based on robust, independently generated performance data collected across multiple sites and seasons. The absence of an equivalent, widely recognised system for SRC willow has been a longstanding gap that could have caused growers to have limited confidence. The Biomass Connect platform represents an important step towards addressing this gap. For the first time, willow varieties originating from multiple breeders have been evaluated side-by-side under an independently managed trial network, providing growers, advisors and policymakers with a transparent comparison of varietal performance. This creates a stronger evidence base for variety selection and begins to establish the foundations for a more formalised approach to willow variety evaluation in the UK.
A variety guide is essential to prospective growers as best practice guidance dictates that SRC willow plantations need to be planted as mixtures of six genetically diverse varieties. There are around 30 available willow varieties and numerous near market genotypes that have been through several rounds of testing, selection and destructive and non-destructive yield assessment.
Many of the current crop of varieties have a common ancestry which makes them vulnerable to pests and disease if mixed with other similar varieties. Knowledge of creating the most robust mixture is therefore of the utmost importance. The guide will include the latest yield data from five willow variety trials planted as part of the Biomass Connect project. These trials are based in:
Northern Ireland
AFBI, Hillsborough,
Scotland
SRUC Boghall, Edinburgh
Wales
IBERS, Aberystwyth
England
Niab, Headley Hall, Yorkshire
Rothamsted Research, North Wyke, Devon
Backed by the Industry and Research bodies
Although this is not strictly a “recommended list” it has backing from all the main parties in the emerging willow industry and research partners.
The guide will cover willow varieties from five breeding programmes (two in Sweden, one in Hungary and two in UK). Additional variety specific data from other trials will also be included. The output will be one of the most definitive guides to willow varieties ever produced.
The guide will include information on those varieties which are highly recommended for yield and quality and have a good deal of supporting evidence to justify this.
Other varieties will be classed as:
Emerging varieties / near market genotypes (for which excellent results have been achieved but there is a more limited body of evidence)
Becoming outclassed (previously useful varieties that have been superseded by better performing ones in terms of yield, disease and pest resistance etc.
No longer recommended (varieties that are no longer suitable for planting due to issues with yield, quality or pests and disease).
What the variety guide would include
For each variety the following information will be included
Progeny (details of hybridisation and genetic background)
Breeder
Plant Breeders Rights details
Gender
Similarity to other varieties and good partners for mixtures
Variety yield data averages and performance versus industry standard (Tora)
Height and diameters
Quality aspects (erect habit, branching and waviness of stems)
Descriptions and identification pointers
Disease and pests scoring
Markets and value chains such as
Woodfuel
Fodder and bio-supplements
Animal bedding
Flood mitigation and water quality management
Compost production
Ecosystem services and environmental benefits
Images of leaves, stems, stools
Colour coding for appropriate mixing with other varieties
Image: Energy Crop Consultancy - Willow harvesting into wood chips
Additional elements covered by the variety guide
An important element will be how to source different varieties. Many of the Swedish varieties would need to be imported. This is expensive, laborious and risky. This would be outlined so prospective growers understand the risks involved.
Most of the varieties are protected by Plant Breeders Rights. The guide will include information outlining the difference in yield between willow varieties bred for biomass, named but unimproved clones and native seedlings. It is important that growers know about the yield potential capabilities of each type.
Importance of Long-Term Monitoring
While the results from the first harvest rotation provide valuable insights into varietal performance, they represent only the initial stage of crop evaluation. Willow productivity, persistence and economic performance are strongly influenced by responses across successive harvest cycles. Differences between varieties in vigour and long-term yield stability may become more apparent during later rotations. There is therefore a strong case for maintaining these trials through subsequent harvest cycles and continuing independent performance assessments.
The Biomass Connect variety trials represent more than a single assessment of yield performance; they are the first step towards establishing an evidence-based framework for willow variety evaluation in the UK, analogous to the Recommended Lists that underpin variety selection across the country's major agricultural crops.
Come back soon to find out more and get the
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