Morphological and physiological response to competition in alder, eucalyptus and spruce

Susie Foreman

ShortFor project conference 11th December 2017

• SRF in Ireland – establishment

• Response to competition

• Preliminary findings

Presentation content

Objective: to study the effect of planting density on the growth and physiological responses of selected short-rotation forestry (SRF) species

PhD: Jan 2015-Dec 2018

Establishment of trial at Johnstown Castle

Establishment of experiments at Kinsealy Research Centre

Species selected

Eucalyptus nitens (Shining gum) (EN)

Alnus cordata (Italian alder) (IA)

Picea sitchensis (Sitka spruce) SS

Polytunnel experiment Purpose:

• maximise measurement

and experimentation period

• controlled conditions

• increased replications

• Inform trial measurements

Randomised block design 3 species and 3 spacings

Density – per pot

Low 1 plant Medium 4 plants High 8 plants

Research completed at Kinsealy

Morphology

• Tree height • Stem basal diameter • Branch length and number • Specific leaf area Physiology

• Flushing and senescence • Light interception • Chlorophyll concentration • Photosynthesis Destructive sampling

• Biomass

Morphology

Specific leaf area and chlorophyll concentration

Photosynthesis rate

PAR 1000 (µmol m-2 s-1)

Biomass after 9 months growth

Taken forward to field trial

• Stem height and basal diameter • Branch length • Extra - Green canopy depth

• Canopy position • Photosynthesis at PAR 1000 µmol m-2 s-1 • Chlorophyll concentration • Light interception analysis (LAI)

• Biomass?

Field trial Johnstown Castle

Planted in June 2014

EN 0.5X0.5

EN 1X1

EN 2X2

EN 2.5X3.0

IA 0.5X0.5

IA 1X1

IA 2X2

IA 2X3

SS 0.5X0.5

SS 1X0.5

SS 1X2

SS 2X2

Spacing

Chlorophyll content in field conditions Shade leaves only

PAR 1000 µmol m-2 s-1

Photosynthesis rates Shade leaves only

• Effect of spacing on: • Growth

• Photosynthesis rate

• Biomass

Main findings

• Species potential

• Inform silviculture practices for SRF

Initial spacing Rotation length Interventions Manipulations

Preliminary conclusions

Alder

Eucalyptus

Spruce

Acknowledgements

Any questions