What Do Fast-Growing Plantations Really Replace? A Better Baseline for energy crop's LCA

Environmental assessments of fast-growing plantations often begin with a deceptively simple assumption: that the plantation replaces an average cereal field. Yet, a realistic baseline is not a technical detail. It is part of the system being assessed. Whether willow, poplar or hybrid aspen replaces winter wheat, spring barley, temporary grassland or fallow land can substantially influence estimates of greenhouse-gas balances, soil carbon, nutrient losses, biodiversity effects and opportunity costs. For this reason, understanding where plantations are established, and what they replace, is essential for credible life-cycle assessment, land-use modelling and bioeconomy planning.

A 30-year assessment of fast-growing plantations in Sweden provides one of the most detailed empirical baselines currently available. The study traced the development of willow, poplar and hybrid aspen plantations between 1986 and 2017, combining plantation records, agricultural land-register data and spatial analysis. The results showed that willow remained the dominant system, but its area declined from approximately 14,000 ha around 2001 to 7,785 ha in 2017. Poplar and hybrid aspen partly offset this decline, reaching 1,738 ha and 676 ha, respectively, by 2017. In total, Sweden still maintained approximately 10,200 ha of fast-growing woody plantations, although their composition, location and agricultural context changed markedly over time. The full analysis is available here.

The results also showed that plantation establishment cannot be separated from changing policies and agricultural markets. Willow expansion was initially linked to Swedish policy support for energy crops, whereas its subsequent decline coincided with reduced incentives and rising cereal prices after 2007. Average cereal prices increased sharply relative to the 1990–2006 period, by approximately 49% for wheat, 40% for barley and 22% for oats. At the same time, many former willow plantations returned to cereal cultivation. However, new plantations were not established only on cereal land. In 2016, new willow plantations were commonly associated with former spring barley, winter wheat, temporary grassland and fallow land. Poplar plantations showed an even clearer association with lower-intensity agricultural land uses, particularly fallow land and temporary grass. These replacement patterns provide a practical basis for defining differentiated reference scenarios.

This distinction matters greatly for LCA. A plantation replacing intensively managed cereal land may generate different environmental trade-offs than one established on fallow land or temporary grassland, where fertiliser use, machinery inputs and baseline carbon dynamics are already lower. Treating all plantation establishment as a cereal-to-wood transition may therefore overestimate some environmental benefits or overlook relevant impacts. Rather than relying on a single generic counterfactual, future assessments could use a weighted portfolio of agricultural reference systems, reflecting the observed shares of cereals, grasses and fallow land replaced by each plantation type. Such an approach would make evaluations of short-rotation woody crops more spatially realistic, more transparent and more relevant for policy.

The study also illustrates that plantation systems are dynamic rather than uniform. Willow plantations increasingly concentrated in southern and more productive agricultural areas, whereas poplar tended to expand on less productive land. Smaller plantation units became more frequent, particularly those below one hectare, while large systems above ten hectares became relatively uncommon. These patterns reflect not only land availability, but also changing farmer preferences, local biomass markets, management choices and wider agricultural conditions. For researchers seeking robust baseline scenarios for plantations, the central message is clear: the environmental performance of a plantation cannot be assessed independently from the land-use trajectory that made it possible.

Further information: Research on biomass production, plantation forestry and land-use dynamics is available through the Biomass Production research group at the University of Eastern Finland. Further publications and activities can also be found at sites.uef.fi/biopro.

Reference

Xu, X., & Mola-Yudego, B. (2021). Where and when are plantations established? Land-use replacement patterns of fast-growing plantations on agricultural land. Biomass and Bioenergy, 144, Article 105921. https://doi.org/10.1016/j.biombioe.2020.105921

For related research, visit the Biomass Production research group, University of Eastern Finland.

Mapping yields of energy crops in Northern Europe

Willow plantations have long been considered a promising option for #bioenergy in northern Europe. But a basic question remains essential for both investors and #policy makers: how much biomass can actually be produced, and where. It is easy to speak about potential in general terms, but supply planning requires something much more concrete, spatially explicit estimates grounded in real production data.

In this study, we used harvesting records from 1,790 commercial willow plantations in Sweden and combined them with climatic variables to estimate productivity across northern Europe. Rather than relying only on experimental plots, the work was based on commercial plantations, which makes the estimates closer to the biomass that can realistically be harvested and mobilised in practice. The models were then extended to Sweden, Norway, Denmark, Finland, Estonia, Latvia, Lithuania, and the Baltic coastal areas of Germany and Poland.

What we found was a strong spatial variability in yield potential. Precipitation during the growing season, together with key temperature variables, explained an important part of that variation. Under high-performance conditions, average first-rotation yields were above 7 odt ha⁻¹ yr⁻¹ in the Baltic coast of Germany, above 6 in Denmark, above 5 in the Baltic coast of Poland, and between 4 and 5 in much of the remaining study area. This matters because it shows that not all land, and not all regions, offer the same opportunity for energy crops, even within relatively similar climatic zones.

This is, in my view, where the practical value of the study lies. Biomass strategies should not be discussed only in terms of total land availability, but also in terms of realistic productivity, regional differences, and the climatic limits of the crop. Better spatial estimates can improve hashtag#energysystems planning, reduce overly optimistic assumptions, and support more informed decisions on where willow can be a viable part of the renewable energy mix.

At the same time, the study also reminded us of something important: climate explains much, but not everything. Soil conditions, clone choice, and management still matter greatly, especially in the most productive plantations. In that sense, these maps should not be read as fixed truths, but as a solid reference for planning, comparison, and future improvement. For #bioeconomy and #renewableenergy, that is already a very useful step forward.

Download the TIF layers:

gcbb12332-sup-0001-FigS1.tifTIFF image, 5.9 MB	Figure S1. Yield estimates based on climatic variables at 1 × 1 km resolution for willow plantations on agricultural areas of northern Europe for a lowest performance scenario.
gcbb12332-sup-0002-FigS2.tifTIFF image, 5.9 MB	Figure S2. Yield estimates based on climatic variables at 1 × 1 km resolution for willow plantations on agricultural areas of northern Europe for a middle performance scenario.
gcbb12332-sup-0003-FigS3.tifTIFF image, 5.5 MB	Figure S3. Yield estimates based on climatic variables at 1 × 1 km resolution for willow plantations on agricultural areas of northern Europe for a highest performance scenario.
gcbb12332-sup-0004-Appendix.docxWord document, 249.7 KB	Appendix S1. Average yield response (marginal effect) by climatic variable.

Source: Mola-Yudego, B., Rahlf, J., Astrup, R., & Dimitriou, I. (2016). Spatial yield estimates of fast-growing willow plantations for energy based on climatic variables in northern Europe. GCB Bioenergy, 8, 1093–1105. https://doi.org/10.1111/gcbb.12332

Where Biomass Belongs: Mapping Europe’s Energy Crops to Build More Diverse Landscapes

As Europe accelerates its shift toward a low-carbon economy, the pressure to deliver sustainable biomass is rising fast, yet the hardest question is no longer only what to grow, it is where to grow it. Fast-growing plantations and perennial energy grasses can underpin biofuels and biomaterials, while also supporting carbon storage, water protection, and soil functions. However, when these systems expand as large, poorly integrated blocks, they can simplify land use patterns, weaken habitat variety, and reduce ecological resilience. The promise of the bioeconomy, therefore, depends on spatial intelligence: biomass systems need to be placed as part of the landscape, not imposed on top of it.

A recent open-access study addressed this challenge by building one of the most comprehensive empirical pictures yet of biomass production systems across Europe. Using harmonised spatial data for 426,783 fields and stands, covering 2,140,568 hectares across 17 countries, the authors characterised seven representative systems, including eucalypt, radiata pine, black locust, poplar and hybrid aspen, willow, miscanthus, and reed canary grass. They then assessed the land-use context around each site using 1 km buffers and CORINE land cover, translating “how mixed is the surrounding landscape?” into a Land Use Diversity Index based on Shannon diversity. The result was a practical lens for policy and planning: it showed not just where biomass is today, but where it is likely to diversify, or homogenise, the landscapes around it.

The key insight was that context dominates: the same crop can be either a corridor of diversity or an engine of simplification, depending on where it is inserted. Willow stood out as the strongest candidate for diversification, with 57% of willow plantations located in homogeneous, agriculture-dominated areas, where woody strips can introduce structural variety and potentially strengthen multifunctionality. Poplar and black locust also showed meaningful opportunities, with sizeable shares of stands situated where they could add “forested elements” into agricultural matrices. By contrast, miscanthus was often concentrated in low-diversity agricultural settings, suggesting that, without deliberate spatial planning, it may do little to raise local land-use diversity. The study also highlighted a recurring risk signal: biomass areas were highly unevenly distributed, with the largest 20% of stands accounting for the majority of total area, and thousands of very large polygons, a pattern that can translate into landscape dominance when not carefully governed. A sustainable bioeconomy is a design problem, and better maps, better metrics, and better placement rules are as important as better crops.

Read more:
Pineda-Zapata, S., & Mola-Yudego, B. (2025). European biomass production systems: Characterization and potential contribution to land use diversity. GCB Bioenergy, 17, e70057. https://doi.org/10.1111/gcbb.70057
DOI: 10.1111/gcbb.70057