NATSEED – species-specific seed sampling strategies for native trees
Since its launch in April 2025, the NATSEED project has focused on improving our understanding of native tree seed sources in Ireland and the methods used to assess seed quality, Saoirse O’Neill Field, NATSEED Project Research Technician, Teagasc; Dheeraj Singh Rathore, Tree Improvement Research Officer, Teagasc, Colin Kelleher, Taxonomist & Keeper of the Herbarium, National Botanic Gardens of Ireland; and Patrick Langan, NATSEED Project Postdoctoral Researcher, National Botanic Gardens of Ireland, tell us more.
The NATSEED project, coordinated by the National Botanic Gardens of Ireland (NBG) in collaboration with Teagasc Forestry Development Department, is funded under the Department of Agriculture, Food and the Marine’s Policy and Strategic Studies Research Call (Grant No. 2024PSSRC362). The project focuses on strengthening species-specific seed sourcing strategies for priority native tree species in Ireland. Since its launch in April 2025, the NATSEED project has focused on improving our understanding of native tree seed sources in Ireland and the methods used to assess seed quality.
The project covers eight native tree species of ecological and economic importance including alder, downy birch, silver birch, Scots pine, pedunculate oak, sessile oak, hazel and holly. Our stakeholders include Coillte, None-So-Hardy Nurseries and Woodlands of Ireland.
The species included in the NATSEED project. Illustrations were kindly provided by the Tree Council of Ireland
Seed variability and mast years
Native tree species do not produce consistent seed crops each year. Periodic mast years can generate large volumes of seed, followed by years of limited seed availability. Without a structured approach to collection, testing and storage, the opportunities during high-yield years may be underutilised. NATSEED is examining seed sources, storage challenges and testing methods which could in turn help to optimise our response during a mast year.
Our approach
NATSEED applies a structured and evidence-based approach to strengthen seed sourcing strategies for priority native species. The work integrates desk-based analysis, laboratory testing and genetic assessment to build a clearer understanding of both seed origin and performance. Key components include:
- A comprehensive desk study and stakeholder engagement to identify seed sources
- GIS-based assessment for distribution patterns and capture of genetic variation
- Germination and seed quality testing across species
- Molecular characterization of hazel and holly to study genetic diversity in Ireland
Teagasc’s role focuses on seed testing, germination trials and technical assessment, carried out at Teagasc Oak Park and in collaboration with the Seed Testing Laboratory at the Department of Agriculture, Food and the Marine (DAFM).
Assessing storage effects in alder and birch
A specific strand of the work has examined the impact of storage on alder and downy birch seed viability. Laboratory analysis included:
- Thousand seed weight
- Moisture content
- Tetrazolium viability testing
- Standard germination testing
All assessments followed International Seed Testing Association (ISTA) protocols.
This work provides practical insight into how storage duration and conditions may influence seed performance, particularly for species where supply can fluctuate significantly between years.
Current focus
The project is currently consolidating germination and seed quality data collected during 2025, integrating new testing results with existing datasets. Molecular analysis of hazel and holly is also progressing in the NBG, including DNA extraction, sequencing and estimation of genetic variation.
The overall aim is to contribute to the development of species-specific seed sourcing recommendations for the target species, alongside general guidance applicable to other native Irish trees. The work supports informed decision-making around collection, testing and storage, helping to strengthen long-term seed supply resilience.
Further information on Teagasc’s NATSEED project is available here.
Featured image: Photo of alder saplings taken during a a visit to None-So-Hardy’s nursery in June 2025