Nearly 70 cultivated varieties
in Canada.

Salix miyabeana, viminalis, purpurea, dasyclados and their hybrids: Ramo grows nearly 70 willow varieties in Saint-Roch-de-l'Achigan, in the largest willow-specialized nursery in North America. Here is why that diversity matters and how each variety finds its place.

There is no such thing as “the” willow

The genus Salix includes 330 to 500 species. Environmental uses focus on a handful, selected for yield, adaptation and hardiness¹. Some stand out for growth, others for biomass, tolerance of northern climates or the ability to establish on degraded sites.

Ramo's 70 varieties were selected over nearly twenty years of trials, projects and collaborations with the research community.

Why so many varieties?

Because there is no perfect variety. Quebec trials show that performance varies widely from one cultivar to another, even under similar conditions², and that the interaction between genotype and environment weighs heavily on yields³. Some varieties excel in wet soils, others on constrained sites or where biomass is the priority.

For Ramo, genetic diversity is not a luxury: it is a design tool.

The main families Ramo uses

Salix miyabeana

The flagship species of Quebec projects. Growth, high evapotranspiration and good adaptation to the climate make it the preferred choice for Evaplant® and Evacap™; the SX67 cultivar was studied in a full-scale treatment wetland in Quebec⁴.

Salix viminalis

The benchmark for short-rotation plantations, productive and fast, useful for the ramial chipped wood (RCW) stream.

Salix dasyclados and Salix purpurea

The first, vigorous and hardy, strengthens the resilience of mixes. The second, more compact and dense, is used for screens and fences. Many hybrids combine these qualities.

Native willows

To stabilize banks and restore agricultural gullies, Ramo relies mainly on native willows (pussy willow, woolly-headed willow, shining willow, black willow, among others) depending on their position in the gully⁵. These species can also restore disturbed sites in eastern Canada⁶.

How do we choose the right variety?

The choice always starts with the site. Ramo's team looks at:

• Climate: growing season, temperatures, precipitation, frost risk.
• Soil: texture, drainage, fertility, compaction, contaminants.
• Objective: reducing water volumes, biomass, revegetation, restoration, visual screen.
• Constraints: access, maintenance, available area, regulatory requirements.

Variety selection is therefore an integral part of project design.

Diversity, for resilience and biodiversity

Planting a single variety simplifies operations but raises the risks. Biomass, root development and stress tolerance vary widely from one genotype to another⁷: mixing varieties protects the plantation against disease, insects and climate extremes.

The ecological effect is measurable too. In a plantation of 30 cultivars, a North American study recorded 57 species of wild bees, several of them rare or declining⁸. Since male willows produce pollen and nectar while females offer nectar only, we combine several pedigrees and both sexes when a project targets biodiversity.

Saint-Roch-de-l'Achigan: production and trials

The Saint-Roch-de-l'Achigan nursery, northeast of Montreal, produces millions of cuttings every year, harvested, sorted and prepared for projects. Ramo thereby controls the whole chain, from genetics to the field, and safeguards a varietal heritage built over nearly twenty years.

It is also an open-air laboratory where new varieties are evaluated continuously. Trials extend into the north: at ArcelorMittal's Mont-Wright mine in Fermont, several varieties are being tested in a northern mining context, in line with work showing willow's potential on mining sites, even in acidic conditions⁹. The results feed directly into the choices made in projects.

Scientific sources

1. Labrecque, M., & Lajeunesse, S.-L. (2017). Guide de production de saules en culture intensive sur courtes rotations.
2. Labrecque, M., et al. (2022). Comparing biomass yields of various willow cultivars over 6 years in Quebec.
3. Fabio, E. S., et al. (2017). Genotype × Environment Interaction Analysis of Willow Yield.
4. Frédette, C., Grebenshchykova, Z., Comeau, Y., & Brisson, J. (2019). Evapotranspiration of a willow cultivar (Salix miyabeana SX67) grown in a full-scale treatment wetland. Ecological Engineering, 127, 254-262.
5. Habitat-Nature (2022). Fiches techniques : limiter l'érosion et la pollution agricole en restaurant des coulées agricoles. Fiducie écosystèmes Lanaudière. www.habitat-nature.com
6. Mosseler, A., Major, J. E., & Labrecque, M. (2014). Growth and survival of seven native willow species on highly disturbed coal mine sites in eastern Canada. Canadian Journal of Forest Research, 44(4), 340-349.
7. Sleight, N. J., et al. (2023). Belowground Biomass and Root-Shoot Ratios of Three Willow Cultivars at Two Sites.
8. Tumminello, G., Volk, T. A., & Heavey, J. P. (2017). Pollinator Benefits, Shrub Willow Fact Sheet Series. SUNY-ESF.
9. Mosseler, A., & Major, J. E. (2014). Coppice growth responses of two North American willows in acidic clay soils on coal mine overburden. Canadian Journal of Plant Science, 94(7), 1269-1279.