Fertilization of Western Fertilization of Western RedcedarRedcedar

((Thuja plicataThuja plicata))

R.W. NegraveR.W. NegraveCoast Region, MFRCoast Region, MFR

Western Redcedar Western Redcedar FertilizationFertilization

Fertilization studiesFertilization studies

Harrington and WiermanHarrington and Wierman

SCHIRPSCHIRP

Fertilization StudiesFertilization Studies

Commercial thinning/ fertilization Commercial thinning/ fertilization (WA)(WA)

SCHIRP: North Island, Kennedy FlatsSCHIRP: North Island, Kennedy Flats

WFP monitoring of operational trialsWFP monitoring of operational trials

Harrington and Wierman Harrington and Wierman (1990)(1990)

Thinning and fertilization with Thinning and fertilization with different products different products

Stands were 15 – 20 yrs old on poor Stands were 15 – 20 yrs old on poor sitessites

Reported five years after treatmentReported five years after treatment

Harrington and Wierman: Harrington and Wierman: Seven TreatmentsSeven Treatments

UntreatedUntreated Unthinned + NH4 + Ca + P + K + SUnthinned + NH4 + Ca + P + K + S Thinned, unfertilizedThinned, unfertilized Thinned + Urea-NThinned + Urea-N Thinned + NH4Thinned + NH4 Thinned + NH4 +Ca + PThinned + NH4 +Ca + P Thinned + NH4 + Ca + P + K + SThinned + NH4 + Ca + P + K + S

Harrington and Wierman: Harrington and Wierman: Application RatesApplication Rates

300 kg/ha N (urea; ammonium 300 kg/ha N (urea; ammonium nitrate)nitrate)

100 kg/ ha P (dicalcium phosphate)100 kg/ ha P (dicalcium phosphate) 129 kg/ ha Ca (dicalcium phosphate)129 kg/ ha Ca (dicalcium phosphate) 100 kg/ ha K (potassium sulphate)100 kg/ ha K (potassium sulphate) 41 kg / ha S (potassium sulphate)41 kg / ha S (potassium sulphate)

Harrington and Wierman: Harrington and Wierman: ResultsResults

Height and diameter growth were significantly Height and diameter growth were significantly greater in all thinned or fertilized treatments, greater in all thinned or fertilized treatments, compared to untreatedcompared to untreated

The best treatments for height (+65%) and The best treatments for height (+65%) and diameter growth (+106%) contained ammonium diameter growth (+106%) contained ammonium nitrate and dicalcium phosphatenitrate and dicalcium phosphate

Ca and P additions increased growth over N aloneCa and P additions increased growth over N alone

Thinning was also produced substantial diameter Thinning was also produced substantial diameter growth responsegrowth response

SCHIRP TrialsSCHIRP Trials

Kennedy Flats and N. Vancouver IslandKennedy Flats and N. Vancouver Island

Kennedy Flats trial in general Kennedy Flats trial in general agreement with N. Vancouver Island agreement with N. Vancouver Island trialtrial

Scarification appears to have a positive Scarification appears to have a positive effect on growth; slight interaction with effect on growth; slight interaction with fertilizationfertilization

SCHIRP NVI: TreatmentsSCHIRP NVI: Treatments

Two sites: CH and HATwo sites: CH and HA Two species: Cw HwTwo species: Cw Hw Fertilized and unfertilizedFertilized and unfertilized

225 kg/ha as urea225 kg/ha as urea 100 kg/ ha as triple superphosphate100 kg/ ha as triple superphosphate NPK at plantingNPK at planting

Three establishment densities:Three establishment densities: 500, 1500 and 2500 sph500, 1500 and 2500 sph

0

1

2

3

4

5

6

7

8

1988 1990 1992 1994 1996 1998 2000 2002 2004

He

igh

t (m

)

F0-500

F0-1500

F0-2500

F1-500

F1-1500

F1-2500

Cw on CH

0

1

2

3

4

5

6

7

8

9

1988 1990 1992 1994 1996 1998 2000 2002 2004

He

igh

t (m

)

F0-500

F0-1500

F0-2500

F1-500

F1-1500

F1-2500

Cw on HA

0

20

40

60

80

100

120

140

Cw Hw Cw Hw

CH HA

Volu

me

Resp

onse

(m3/

ha)

500 sph

1500 sph

2500 sph

Volume Response to Fertilization

Summary of EffectsSummary of Effects

Fertilization continued to increase Fertilization continued to increase height growth after 10 yearsheight growth after 10 years

Greatest volume response on HA Greatest volume response on HA

Still deficient to very deficient in N Still deficient to very deficient in N

Future Growth?Future Growth?

Growth patternGrowth pattern

Magnitude of responseMagnitude of response

Nutrient concentrations and associations Nutrient concentrations and associations with growthwith growth

Foliage massFoliage mass

-0.2

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

2.0

1988 1990 1992 1994 1996 1998 2000 2002

He

igh

t G

row

th R

es

po

ns

e (

m)

Cw 500

Cw 1500

Cw 2500

Hw 500

Hw 1500

Hw 2500

CH Sites

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

2.0

1988 1990 1992 1994 1996 1998 2000 2002

He

igh

t G

row

th R

es

po

ns

e (

m) Cw 500

Cw 1500

Cw 2500

Hw 500

Hw 1500

Hw 2500

HA Sites

Nutritional Response: 10 Years Nutritional Response: 10 Years LaterLater

Fertilization increased foliarFertilization increased foliar::

N concentration on HA but not CHN concentration on HA but not CH

P and Ca concentration in both P and Ca concentration in both species on both sitesspecies on both sites

Favourable IndicatorsFavourable Indicators

Volume response and total volumes greatest on HAVolume response and total volumes greatest on HA

Indications of more sustained incremental height Indications of more sustained incremental height growth on HAgrowth on HA

N, P, and Ca concentrations all increased on HA and N, P, and Ca concentrations all increased on HA and associated with growth: No evidence of dilutionassociated with growth: No evidence of dilution

Crown closure associated with better incremental Crown closure associated with better incremental height growth responseheight growth response

Stand-level nutrient demands generally stabilize with Stand-level nutrient demands generally stabilize with crown closurecrown closure

Unfavourable IndicatorsUnfavourable Indicators

Volume response less on CHVolume response less on CH

Loss of foliar-N concentration effect Loss of foliar-N concentration effect on CHon CH

Reduced height growth with Reduced height growth with increasing density on CHincreasing density on CH

Individual Cw Foliage Mass Individual Cw Foliage Mass

Foliage mass increased with nutrientFoliage mass increased with nutrient

regime:regime:Foliage Mass (kg)Foliage Mass (kg)

CH-F0:CH-F0: 2.15a2.15a

CH-F1:CH-F1: 3.73b3.73b

HA-F1:HA-F1: 5.96c5.96c

Foliage - Growth Foliage - Growth RelationshipsRelationships

0

1

2

3

4

5

6

7

8

0 2 4 6 8 10 12

Foliage Mass (t/ha)

Biom

ass

Incr

emen

t (t/h

a/yr

)

No Fert.

Fertilized

Cw on HA

r 2 = 0.983

General ConclusionsGeneral Conclusions

Magnitude and duration of Cw response to Magnitude and duration of Cw response to fertilization are comparable to Fdfertilization are comparable to Fd

No indications of negative growth response: No indications of negative growth response: trajectories likely parallel or better at SCHIRPtrajectories likely parallel or better at SCHIRP

Cw appears to respond well at higher Cw appears to respond well at higher densitiesdensities

Greater response implied by higher Greater response implied by higher application rates; ammonium; Caapplication rates; ammonium; Ca