Flowering biology
• Differences between species
• Flowering and seed development cycle.
• Factors affecting seed production.
Eucalyptus nitens seed
development cycle
June Year 1 Feb Year 2 Nov Year 2
Jan Year 3Feb Year 4Feb Year 5
Objectives of Seed Orchard
Management
• Early flowering;
flowering can begin at 3
years for E. nitens.
• Simultaneous flowering
between trees; ensures
out-crossing.
• Promote abundant
flowering and abundant
seed crops.
Seed yields for E. nitens
• Some sites produce very little
seed. Quoted seed crops are
usually less than 100 g per
tree.
• Crops of 1 kg seed per tree
are possible (200,000 seeds).
• Site conditions and
management important for
good seed production.
Factors affecting seed
production -Eucalypts
• Hormone treatments
• Nutrition – Fertiliser ( P & K )
•Spacing and topping
• Irrigation
• Genetics
•Environment