Post by Mateusz Liziniewicz

🌱 Can timing alone change germination success by more than 4-fold? In tree breeding and propagation, we often focus on genetics — selecting the right families, identifying superior genotypes, making the right crosses. But sometimes, a very practical factor can make just as much difference: timing. Recently, we tested germination of green-collected ash (Fraxinus excelsior) seeds from 27 families, collected on four different occasions between 19 August and 16 September. The objective was simple: understand how collection timing affects the ability to quickly produce seedlings. In a long run it is to produce ash plants without a year of delay as ash seeds tend to start a deep dormancy when collected late in the year. The results were striking. 📊 Seeds collected on 19 August produced 4.6 times more germinated seedlings than seeds collected on 16 September. Many families did not germinated at all already on 16 September. Across all families, germination declined steadily with later collection dates. Interestingly, while all families followed the same general trend, some maintained higher germination for longer — suggesting that genetic differences may also influence seed maturation dynamics. Why does this matter? For breeding programs, time is often the biggest bottleneck. Faster propagation means: ✅ quicker establishment of progeny tests ✅ faster multiplication of valuable genotypes ✅ earlier graft production for seed orchards ✅ shorter breeding cycles This practical experiment is a good reminder that improving operational breeding is not always about advanced genomics or complex statistics. Sometimes, optimizing when we do things can unlock huge gains. In breeding, timing matters. Now we are quite sure that generally meant "green seeds", in Swedish context mean seeds collected already in August 😀 (Infographic below summarizing the results 👇) #Forestry #TreeBreeding #ForestGenetics #AshDieback #FraxinusExcelsior #SeedBiology #PlantPropagation #Skogforsk #ForestResearch #TreeImprovement #BreedingInnovation #SustainableForestry