Cone Handling, Monitoring and Tree Seed Centre Overview BCSOA 2016 Dave Kolotelo Dave.Kolotelo@gov.bc.ca
Overview • Cone Handling BCSOA 2014 Cone Maturation, Collection, Storage and Handling http://www2.gov.bc.ca/assets/gov/farming-natural-resources-and- industry/forestry/docs/tree-seed-docs/tree-seed- centre/cone_maturation_collection_storage_and_handling_bcsoa_14.pdf • Tree Seed Centre http://www2.gov.bc.ca/gov/content/industry/forestry/managing-our- forest-resources/tree-seed • The Interface – think of seedlot or seedling production as a relay – it’s the baton handoffs that are really critical! Communication and better understanding of each others activities and bottlenecks This applies within facilities as well as between
Baseline Biology = “Common Sense” 1. Variation is the rule with conifers – the trick is knowing when to split and when to lump (i.e. clones, SPU) 2. Higher the cone moisture content the greater chance of damage or incomplete seed extraction 3. The earlier the collection relative to natural dispersal (i.e. higher moisture) the more attention needs to be paid to post-collection handling 4. Impurities in a collection can add moisture, pests or physically damage seeds 5. Final germination is a function of collection timing, cone handling, processing and seed pretreatment.
Crop Handling Sequence Things you can influence other than seed set Moisture Purity 1. Cone Collection 40-60% Some facilities Highly 2. Interim Storage at Orchard Site screen off debris Variable 3. Transport (and associated handling) 15-35% 4. Interim Storage at Tree Seed Centre 12-30% 5. Cone Processing (Kilning/air drying) 8% 6. Seed Processing 7% 7% 97% + 7. Long-term Storage
One Time Activities • Collection, post-collection handling, transport & processing • Care, organization and $ invested at these stages will be ‘captured’ for the entire life of a seedlot (not the place to be cheap) • Do you only quality assure your cones during development? until they are in the sacks? Until they leave your site? • Do you know what conditions your harvested cones experienced? “Risk Management” requires a real appreciation of when risks are greatest and what the costs of failure are
• Maximum cone dry weight achieved prior to full maturation ( Anatomical → Physiological) • Very high initial moisture content (60%+) • Cone drying is accompanied by build-up of storage components in megagametophyte and embryo – Simple sugars complex sugars, fats, proteins • Megagametophyte changes from jelly-like to firm and white • Embryo growth is rapid • Conifer seeds are not vascularized • Cones have one vascular strand into bract and two traces into the scale which branch • Embryo nourishment is supplied primarily from embryonic fluid in the corrosion cavity secreted from the megagametophyte
Cone Morphological Observations • Cone maturity is tied to a reduction in moisture and lignification of tissues (woody structure) • Extremes in appearance are obvious – the earliest we can pick cones is not so obvious from cone morphology • cone colour, bract colour, firmness - degree of scale flexing (1953) • Seed or seed wing colour are not great indicators, especially with seed orchard crops – large variability between clones • Seed wing release from cone scale is HIGHLY RECOMMENDED – Separation of seed from ovuliferous scale
Cone “Axis Test” • KAL credit Kudo’s (Chris and Gary) • Assessment of moisture level / cone independence • Quick and easy to perform in the field! • Useful for interior spruce, Douglas-fir and western larch • Cut cone longitudinally – does axis appear brown and dry? Indicating link with tree has been severed • Or does it still contain moisture (Gary suggest running knife blade on axis – look for water droplets )
Collection Timing can have a large Impact on Germination 100% Germination Capacity (%) 90% 80% 70% 60% VSOC 218 50% 40% KAL 307 30% PGTIS 20% 10% Sx - Interior Spruce 0% July 11 July 18 July 25 Aug. 1 Aug. 8 Aug. 15 Aug. 22 Aug. 29 Sept. 5 Sept. 12 Sept. 19 Sept. 26 Collection Date Seeds must reach a stage at which they are independent of the tree for moisture and nutrition
Western Larch Collection Timing
Clonal Intimacy • How we sample – (pest, crop, maturity) Is it representative ? • How we collect? Lumping or Splitting – Down the rows $ – Groups of phenologically similar clones $$ (Early, Mid, Late) – Clonally $$$$ – Within-clone $$$$$$ (orchard hot or cool spots, aspect) • What can you gain by clonal intimacy? – Knowing what to clump or split (extra initial work) • What clones can be collected early – widen the window – Eliminating clones that have germination issues – Flexibility to take advantage of new Breeding Values – Better understanding of real seedlot composition (genomics?)
VSOC Sx Results • Vernon seed orchard company has invested greatly in clonal processing and identifying clones with germination problems in spruce • Some clones had significant, unsolved germination problems – (60-70%; one at 35%) • Elimination was the solution with 8 clones removed from the weevil resistant orchard • Orchard now averages 94% germination
Some yield gains 0.8 through family 0.7 Family Seed Yield (Kg/Hl) processing – not large 0.6 Bulk enough to justify 0.5 additional cost 0.4 0.3 Greatest opportunity 0.2 with Fdc – 0.1 consideration for 0 bumper crops Fdc Pli SX 700 1996 Seeds per Gram 600 1997 Clonal variability 500 400 Year-Year variation in traits 300 and their variability 200 100 0 8 1 1 1 9 8 9 9 1 1 1 5 0 0 0 8 9 9 8 0 … … … … … 9 0 2 9 1
Cone Collection Due Diligence • Use new sacks or properly sterilized sacks (steam/hot water) • Limit amount of debris included (moisture / pests / abrasive) • Move sacks daily from collection site to interim storage • Correct Identification (Outside and Inside sacks) • Fill sacks ½ to ⅓ full to minimize heat build-up / allow cone expansion • Keep sacks off ground / on sides (vs. hanging) to reduce weight • Place sacks in shady, cool environment with good air circulation (fans help!) protected from the elements and pests • Turn sacks to encourage uniformity, discourage clumping – Frequency depends on cone moisture content • Examine cones during cone storage – – Know how your cones look at shipping, not just at picking
Biennial Collection issues • Collecting lodgepole pine cones every two years can be very cost efficient • What are you losing? • Do you know what proportion of your clones retain or lose their serotiny? Clonal Consistency? • Rough estimated range is 10-40% cones are non- serotinous at time of kiln loading for orchard lodgepole • Even without seed dispersal the removal of the serotiny allows a pathogen to enter a usually pathogen-free environment
Cedar Collections • We used to have a strict policy regarding amount of debris in redcedar collections (15%) • There are good reasons to exclude debris, but their may be some advantages with these small cones by improving aeration and assisting uniformity of drying • Removing potential cone sites vs. creating new ones Yes, please No, Thank you No, Thank you
Cone Storage • Goal is to slowly dry the cones and complete maturation process (Anatomical→ Physiological ) maximizing seed extractability & germination • Physiological changes continue after anatomical maturity has been reached ♥ ♥ Serotinous cones can be stacked ♥
How rapidly do Cones lose moisture? • Kalamalka weighed and recorded the same individual cones weekly throughout interim storage in organza bags • Upon receipt at the TSC this was continued until extraction when an oven-dry weight was determined • This allowed us to determine individual cone MC at each date for the same cones ( ≈20 cones per species) • One could also determine filled seed per cone, as most non-serotinous species shed seed before arriving at TSC • Graphs seem to work better with days since collection vs. date (TSWG Newsbulletin)
• The rapid rate of cone drying was quite surprising • Within 2 weeks cones had dried down to 10-12% moisture content • This tells me that this is the time to focus on cone MC – turning sacks + • Don’t know if this is due to the high 2015 temperatures or standard
What Moisture Content Should Cones be? • For Pli, there has been some good work in Alberta (Kare Hellum) • Drier the cone – quicker serotiny is released, moister the cone the greater scale reflection • Best extraction at about 16% moisture content (fw basis) • In terms of seed orchard crops for most species much of the seed is released prior to kilning • Main concern is rate of drying and transportation risks of shipping moist cones • Review of TSC data underway
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