class a western larch seed and interim seed deployment zones barry jaquish and susan zedel tree...
DESCRIPTION
Background Reasons for realized gain testing: 1.Establish allowable cuts 2.Altering forest management regimes to best utilize the growth behavior of improved stock 3.Establishing value of the genetic improvement program 4.Refining selection criteria on the basis of real or predicted final yields 5.Compare yields estimated from progeny tests with area-based tests 2TRANSCRIPT
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Class “A” western larch seed and interim seed deployment zones
Barry Jaquish and Susan ZedelTree Improvement Branch
October 3, 2015
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Forest Seed classification in B.C.
• In B.C., tree seed must be registered with Tree Improvement Branch to be deployed legally on public lands.
• Class “B” – collected in natural stands; no genetic improvement.
• Class “B+” – collected in natural stands that have demonstrated superior growth performance in genetic tests; modest level of genetic improvement in growth and/or pest resistance traits.
• Class “A” - produced in one of the many provincial seed orchards (private or public);
- some level of genetic improvement in value traits (eg. tree volume or pest resistance) assigned to each seedlot.
- level of genetic improvement is determined through an extensive network of genetic tests on field or nursery sites (varies between 10- 35% tree volume at rotation).
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Background
• Reasons for realized gain testing:
1. Establish allowable cuts
2. Altering forest management regimes to best utilize the growth behavior of improved stock
3. Establishing value of the genetic improvement program
4. Refining selection criteria on the basis of real or predicted final yields
5. Compare yields estimated from progeny tests with area-based tests
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Western Larch Realized Gain Genetic Tests
• Established spring 2004
• Design:– 12 x 12 tree square plots
– 3 spacings • (1.5m, 2.5m, 3.5m)
– 4 seedlots• Control (5 wild seedlots)• Seed orchard low GW (6%)• Seed orchard high GW (12%)• Elite – composite 5 full-sib
families
– 2 replications per site
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Western Larch Realized Gain Genetic Tests
Site BEC zone Elev (m) MAT(C)
MAP(mm)
Bear Ck ICHdw1 822 6.0 785
Burton Ck ICHmw2 899 4.4 861
Taurus Ck MSdm1 1242 4.0 579
Burton Bear Taurus100
150
200
250
300
350
400
Nelson western larch realized gain field tests: 6-year height by site
Site
Mea
n he
ight
(cm
)
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Western Larch Realized Gain Genetic Tests
Elite seedlotControl
Burton realized gain test: 4-years-old
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Results
Burton
Bear
Taurus
0 100 200 300 400
6-year height by site and seed type
Control SOlow SOhi Elite
Mean height (cm)
Burton
Bear
Taurus
0 20 40 60 80 100
6-year survival by site and seed type
Control SOlow SOhi Elite
Survival (%)
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Results
Burton
Bear
Taurus
0 50 100 150 200 250 300 350 400
6-year height by site and level of spacing
3.5 x 3.5 2.5 x 2.5 1.5 x 1.5Mean height (cm)
Burton
Bear
Taurus
0 20 40 60 80 100
6-year survival by site and level of spacing
3.5 x 3.5 2.5 x 2.5 1.5 x 1.5Survival (%)
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Results
Elite
SOhi
SOlow
Control
0 100 200 300
6-year height by spacing and seed type
3.5 x 3.5 2.5 x 2.5 1.5 x 1.5Mean height (cm)
Elite
SOhi
SOlow
Control
0 20 40 60 80 100
6-year survival by spacing and seed type
3.5 x 3.5 2.5 x 2.5 1.5 x 1.5Survival (%)
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Conclusions
• Site and seedlot had a significant effect on height at age 6; spacing had little effect;
• Elite and seed orchard seedlots demonstrated 21 % and 10 % greater growth than wild-stand control seedlots, respectively;
• Seedlot growth trends were similar across sites, but differences were more pronounced on productive sites; and,
• Survival similar for all effects.