Foliar Nutrient AnalysisFoliage collection and interpretation of laboratory results

Operational fertilization decision-making

Forest level considerations

Stand level considerations operational factors biological factors

species stand structure crown conditions insect/disease nutrient status

Foliar analysis as a planning tool

Foliar analysis can be used to: confirm N deficiency

Foliar analysis as a planning tool

Foliar analysis can be used to: confirm N deficiency identify secondary nutrient deficiencies (e.g., S, B)

Foliar analysis as a planning tool

Foliar analysis can be used to: confirm N deficiency identify secondary nutrient deficiencies (e.g., S, B) make appropriate fertilizer prescriptions

Foliar analysis as a planning tool

Foliar analysis can be used to: confirm N deficiency identify secondary nutrient deficiencies (e.g., S, B) make appropriate fertilizer prescriptions assess post-fertilization nutrient uptake and foliar

nutrient balance

How much foliar sampling is needed?

How much foliar sampling is needed?

Foliar sampling should only be undertaken on candidate sites that satisfy other forest- and stand-level selection criteria

How much foliar sampling is needed?

Foliar sampling should only be undertaken on candidate sites that satisfy other forest- and stand-level selection criteria

Strategically allocate foliar sampling expenditures

How much foliar sampling is needed?

Foliar sampling should only be undertaken on candidate sites that satisfy other forest- and stand-level selection criteria

Strategically allocate foliar sampling expenditures Utilize foliar nutrient data and/or fertilization

growth response results from similar nearby stands

How much foliar sampling is needed?

Foliar sampling should only be undertaken on candidate sites that satisfy other forest- and stand-level selection criteria

Strategically allocate foliar sampling expenditures Utilize foliar nutrient data and/or fertilization growth response

results from similar nearby stands Stratify candidate blocks into homogeneous

combinations (species, age, BEC, stand history, stand conditions)

How much foliar sampling is needed?

Foliar sampling should only be undertaken on candidate sites that satisfy other forest- and stand-level selection criteria

Strategically allocate foliar sampling expenditures Utilize foliar nutrient data and/or fertilization growth response

results from similar nearby stands Stratify candidate blocks into homogeneous combinations

(species, age, BEC, stand history, stand conditions) Collect representative composite foliage

samples from each major combination

How much foliar sampling is needed?

Foliar sampling should only be undertaken on candidate sites that satisfy other forest- and stand-level selection criteria

Strategically allocate foliar sampling expenditures Utilize foliar nutrient data and/or fertilization growth response

results from similar nearby stands Stratify candidate blocks into homogeneous combinations

(species, age, BEC, stand history, stand conditions) Collect representative composite foliage samples from each

major combination Operational fertilization projects comprised of a

small number of large and uniform blocks will require a relatively small amount of foliar sampling

Factors affecting interpretation of foliar nutrient data

Factors affecting interpretation of foliar nutrient data

Foliar sampling protocol

Foliar Sampling Protocol

Foliar Sampling Protocol

Sample during the dormant season

Seasonal change in foliar %N in Douglas-fir foliage

0.6

0.8

1

1.2

1.4

1.6

1.8

Fo

liar

N (

%)

May June July Aug Sept Oct Nov Dec

Moderate deficiency

Month

Sampling period

Foliar Sampling Protocol

Sample during the dormant season

Sample current year’s foliage

Foliar Sampling Protocol

Sample during the dormant season

Sample current year’s foliage

Collect foliage from between top 1/4 and bottom 1/2 of live crown

Foliar Sampling Protocol

Sample during the dormant season

Sample current year’s foliage

Collect foliage from between top 1/4 and bottom 1/2 of live crown

Collect foliage from healthy, representative trees

Do not collect foliage fromunhealthy trees!!!

Foliar Sampling Protocol

Sample during the dormant season

Sample current year’s foliage

Collect foliage from between top 1/4 and bottom 1/2 of live crown

Collect foliage from representative trees

Collect foliage from at least 20 trees per stand or stratum

Foliar sampling layout

x

x

x

x

x

x

xx

xx

xx

xx

xx

xx

xx

RoadL

ine

1

Line 2

/02

/01

Foliar Sampling Protocol

Sample during the dormant season

Sample current year’s foliage

Collect foliage from between top 1/4 and bottom 1/2 of live crown

Collect foliage from representative trees

Collect foliage from at least 20 trees per stand or stratum

For routine diagnoses, combine equal amounts of foliage from individual trees into one composite sample per stratum

Foliar Sampling Protocol

Sample during the dormant season

Sample current year’s foliage

Collect foliage from between top 1/4 and bottom 1/2 of live crown

Collect foliage from representative trees

Collect foliage from at least 20 trees per stand or stratum

For routine diagnoses, combine equal amounts of foliage from individual trees into one composite sample per stratum

Keep samples cool until foliage is dried

Factors affecting interpretation of foliar nutrient data

Foliar sampling protocol

Site ecological characteristics

from DeLong (2003)

from DeLong (2003)

Factors affecting interpretation of foliar nutrient data

Foliar sampling protocol

Site ecological characteristics

Laboratory analytical methodology

Relationship between foliar N analytical methodologiesdry combustion vs. wet digestion

0.9 1.0 1.1 1.2 1.3 1.4 1.50.8

0.9

1.0

1.1

1.2

1.3

1.4

% N (dry combustion)

% N

(w

et

dig

es

tio

n)

Relationship between foliar S analytical methodologies dry combustion vs. wet digestion

0.06 0.07 0.08 0.09 0.100.05

0.06

0.07

0.08

0.09

% S (dry combustion)

% S

(w

et

dig

es

tio

n)

Accounting for differences in laboratory analytical methodology

Differences may be large enough to affect interpretation

Accounting for differences in laboratory analytical methodology

Differences may be large enough to affect interpretation

Nutrient interpretative criteria do not account for differences in methodology

Accounting for differences in laboratory analytical methodology

Differences may be large enough to affect interpretation

Nutrient interpretative criteria do not account for differences in methodology

Known differences in laboratory analytical results can be used to “normalize” foliar data prior to interpretation

Accounting for differences in laboratory analytical methodology

Differences may be large enough to affect interpretation

Nutrient interpretative criteria do not account for differences in methodology

Known differences in laboratory analytical results can be used to “normalize” foliar data prior to interpretation

“Normalization” requires inter-laboratory comparisons

Accounting for differences in laboratory analytical methodology

Differences may be large enough to affect interpretation

Nutrient interpretative criteria do not account for differences in methodology

Known differences in laboratory analytical results can be used to “normalize” foliar data prior to interpretation

“Normalization” requires inter-laboratory comparisons

The “normalization” process does not make inferences about the quality of foliar nutrient data

Inter-laboratory comparisonPacific Soil Analysis vs. Ministry of Environment

Inter-laboratory comparisonPacific Soil Analysis vs. Ministry of Environment

50 previously collected Pl foliage samples were selected

Inter-laboratory comparisonPacific Soil Analysis vs. Ministry of Environment

50 previously analyzed foliage samples were used

Samples were selected to cover a broad range of species and foliar nutrient levels

Inter-laboratory comparisonPacific Soil Analysis vs. Ministry of Environment

50 previously analyzed foliage samples were used

Samples were selected to cover a broad range of species and foliar nutrient levels

Each sample was thoroughly mixed and split into two sub-samples

Inter-laboratory comparisonPacific Soil Analysis vs. Ministry of Environment

50 previously analyzed foliage samples were used

Samples were selected to cover a broad range of species and foliar nutrient levels

Each sample was thoroughly mixed and split into two sub-samples

One sub-sample was shipped to each lab in December 2012

Inter-laboratory comparisonPacific Soil Analysis vs. Ministry of Environment

50 previously analyzed foliage samples were used

Samples were selected to cover a broad range of species and foliar nutrient levels

Each sample was thoroughly mixed and split into two sub-samples

One sub-sample was shipped to each lab in December 2012

For each nutrient, laboratory results were reviewed and subjected to regression analysis

Inter-laboratory comparisonPacific Soil Analysis vs. Ministry of Environment

50 previously analyzed foliage samples were used

Samples were selected to cover a broad range of species and foliar nutrient levels

Each sample was thoroughly mixed and split into two sub-samples

One sub-sample was shipped to each lab in December 2012

For each nutrient, laboratory results were reviewed and subjected to regression analysis

Based on previous research, equations were selected to “normalize” foliar nutrient data

Inter-laboratory comparisonPacific Soil Analysis vs. Ministry of Environment

50 previously analyzed foliage samples were used

Samples were selected to cover a broad range of species and foliar nutrient levels

Each sample was thoroughly mixed and split into two sub-samples

One sub-sample was shipped to each lab in December 2012

For each nutrient, laboratory results were reviewed and subjected to regression analysis

Based on previous research, equations were selected to “normalize” foliar nutrient data

An Excel spreadsheet was developed to facilitate “normalization” for practitioners

Laboratory foliar N comparison PSAI vs. MoE

0.9 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 2.00.80.91.01.11.21.31.41.51.61.71.81.9

% Nitrogen (MoE)

% N

itro

ge

n (

PS

AI)

y = 0.9584x R2 = 0.959

Laboratory foliar S comparison PSAI vs. MoE

0.08 0.10 0.12 0.14 0.16 0.18 0.200.070.080.090.100.110.120.130.140.150.160.17

% Sulphur (MoE)

% S

ulp

hu

r (P

SA

I)

y = -0.6267x2 + 0.9558xR2 = 0.888

Laboratory foliar SO4-S comparison PSAI vs. MoE

0 100 200 300 400 5000

100

200

300

400

500

600

ppm Sulphate-S (MoE)

pp

m S

ulp

ha

te-S

(P

SA

I)

y = -0.0008x2 + 1.4164xR2 = 0.884

Laboratory foliar P comparison PSAI vs. MoE

0.10 0.15 0.20 0.25 0.30 0.350.10

0.15

0.20

0.25

0.30

0.35

f(x) = 0.949246219750039 xR² = 0.998330009127891

% Phosphorus (MoE)

% P

ho

sp

ho

rus

(P

SA

I)

Laboratory foliar K comparison PSAI vs. MoE

0.10 0.15 0.20 0.25 0.30 0.350.10

0.15

0.20

0.25

0.30

0.35

f(x) = 0.949246219750039 xR² = 0.998330009127891

% Potassium (MoE)

% P

ota

ss

ium

(P

SA

I)

Laboratory foliar Ca comparison PSAI vs. MoE

0.00 0.20 0.40 0.60 0.80 1.00 1.200.00

0.20

0.40

0.60

0.80

1.00

1.20f(x) = 0.359162995512975 x² + 0.734591772839139 xR² = 0.996003359942529

% Calcium (MoE)

% C

alc

ium

(P

SA

I)

Laboratory foliar Mg comparison PSAI vs. MoE

0.06 0.08 0.10 0.12 0.14 0.16 0.18 0.20 0.22 0.240.06

0.08

0.10

0.12

0.14

0.16

0.18

0.20

0.22

0.24f(x) = 1.02490310339437 xR² = 0.99859621254757

% Magnesium (MoE)

% M

ag

ne

siu

m (

PS

AI)

Laboratory foliar B comparison PSAI vs. MoE

0 10 20 30 40 50 60 70 800

10

20

30

40

50

60

f(x) = − 0.0012318676908454 x² + 0.873218070017739 xR² = 0.99735810044827

ppm Boron (MoE)

pp

m B

oro

n (

PS

AI)

Factors affecting interpretation of foliar nutrient data

Foliar sampling protocol

Site ecological characteristics

Laboratory analytical methodology

Availability of reliable foliar nutrient interpretative criteria

Relationship between tree growth and foliar nutrient concentration

Foliar nutrient concentration

Gro

wth

Deficient

Critical Adequate

Toxic

from Carter (1992)

from Brockley (2001)

Revised foliar nutrient interpretative criteria

Revised foliar nutrient interpretative criteria

Information sources: Previously published interpretative criteria

Revised foliar nutrient interpretative criteria

Information sources: Previously published interpretative criteria

Published foliar nutrient and growth response data from Pinus, Picea and Pseudotsuga fertilization studies

Revised foliar nutrient interpretative criteria

Information sources: Previously published interpretative criteria

Published foliar nutrient and growth response data from Pinus, Picea and Pseudotsuga fertilization studies

Unpublished foliar nutrient and growth response data from BC fertilization studies

Revised foliar nutrient interpretative criteria Macronutrients

Foliar concentration (% dry weight)

Element Interpretation Pl Sx Fd N Severely deficient < 1.00 < 0.90 < 1.00 Mod. to severely deficient 1.00 – 1.15 0.90 – 1.10 1.00 – 1.15 Slightly to mod. deficient 1.15 – 1.30 1.10 – 1.30 1.15 – 1.30 Adequate > 1.30 > 1.30 > 1.30 P Severely deficient < 0.08 < 0.10 < 0.11 Mod. to severely deficient 0.08 – 0.10 0.11 – 0.12 0.11 – 0.13 Slightly to mod. deficient 0.10 – 0.12 0.12 – 0.14 0.13 – 0.15 Adequate > 0.12 > 0.14 > 0.15 K Severely deficient < 0.30 < 0.40 < 0.45 Mod. to severely deficient 0.30 – 0.35 0.40 – 0.45 0.45 – 0.55 Slightly to mod. deficient 0.35 – 0.40 0.45 – 0.50 0.55 – 0.60 Adequate > 0.40 > 0.50 > 0.60

Revised March 2012

Revised foliar nutrient interpretative criteria Macronutrients cont’d

Foliar concentration (% dry weight)

Element Interpretation Pl Sx Fd Ca Severely deficient < 0.06 < 0.10 < 0.10 Mod. to severely deficient 0.06 – 0.08 0.10 – 0.15 0.10 – 0.15 Slightly to mod. deficient 0.08 – 0.10 0.15 – 0.20 0.15 – 0.20 Adequate > 0.10 > 0.20 > 0.20 Mg Severely deficient < 0.04 < 0.04 < 0.06 Mod. to severely deficient 0.04 – 0.06 0.04 – 0.06 0.06 – 0.08 Slightly to mod. deficient 0.06 – 0.08 0.06 – 0.08 0.08 – 0.10 Adequate > 0.08 > 0.08 > 0.10 S Severely deficient < 0.06 < 0.06 < 0.06 Mod. to severely deficient 0.06 – 0.08 0.06 – 0.08 0.06 – 0.08 Slightly to mod. deficient 0.08 – 0.10 0.08 – 0.10 0.08 – 0.10 Adequate > 0.10 > 0.10 > 0.10

Revised March 2012

Revised foliar nutrient interpretative criteria Sulphate-S and Boron

Foliar concentration (ppm dry weight)

Element Interpretation Pl Sx Fd SO4-S Severely deficient < 40 < 60 < 100 Mod. to severely deficient 40 – 60 60 – 80 100 – 150 Slightly to mod. deficient 60 – 80 80 – 100 150 – 200 Adequate > 80 > 100 > 200 B Severely deficient < 3 < 3 < 3 Probable deficiency 3 – 6 3 – 6 3 – 6 Possible deficiency 6 – 12 6 – 12 6 – 12 No deficiency > 12 > 12 > 12

Revised March 2012

Revised foliar nutrient interpretative criteria Nutrient ratios

Nutrient ratio

Element Interpretation Pl Sx Fd

N:P Moderate to severe P deficiency > 13 > 11 > 11 Slight to moderate P deficiency 11 – 13 10 – 11 10 – 11 Possible slight P deficiency 10 – 11 9 – 10 9 – 10 No P deficiency < 10 < 9 < 9 N:K Moderate to severe K deficiency > 4.5 > 4.0 > 3.5 Slight to moderate K deficiency 3.5 – 4.5 3.0 – 4.0 2.5 – 3.5 Possible slight K deficiency 2.5 – 3.5 2.0 – 3.0 2.0 – 2.5 No K deficiency < 2.5 < 2.0 < 2.0 N:S Severe S deficiency > 25 > 25 > 25 Moderate to severe S deficiency 20 – 25 20 – 25 20 – 25 Slight to moderate S deficiency 15 – 20 15 – 20 15 – 20 No S deficiencya < 15 < 15 < 15

a Sulphur deficiency will likely be induced by N fertilization if N:S > 13

Revised March 2012

Revised foliar nutrient interpretative criteria Nutrient ratios cont’d

Nutrient ratio

Element Interpretation Pl Sx Fd

N:Mg Moderate to severe Mg deficiency > 30 > 30 > 30 Slight to moderate Mg deficiency 20 – 30 20 – 30 20 – 30 Possible slight Mg deficiency 15 – 20 15 – 20 15 – 20 No Mg deficiency < 15 < 15 < 15

Some basic interpretative rules

Some basic interpretative rules

Confirm that standardized foliar sampling protocol was used

Some basic interpretative rules

Confirm that standardized foliar sampling protocol was used

Assess foliar nutrient status within the context of site ecological characteristics

Some basic interpretative rules

Confirm that standardized foliar sampling protocol was used

Assess foliar nutrient status within the context of site ecological characteristics

Confirm that N deficiency exists before assessing other nutrients

Some basic interpretative rules

Confirm that standardized foliar sampling protocol was used

Assess foliar nutrient status within the context of site ecological characteristics

Confirm that N deficiency exists before assessing other nutrients

Assess S status in the following order of importance:

SO4 > N:S > SOnly assess N:S or S if SO4 status is marginal

Some basic interpretative rules

Confirm that standardized foliar sampling protocol was used

Assess foliar nutrient status within the context of site ecological characteristics

Confirm that N deficiency exists before assessing other nutrients

Assess S status in the following order of importance:SO4 > N:S > S

N:P, N:K, and N:Mg ratios are more important than absolute levels of P, K, or Mg

Some basic interpretative rules

Confirm that standardized foliar sampling protocol was used

Assess foliar nutrient status within the context of site ecological characteristics

Confirm that N deficiency exists before assessing other nutrients

Assess S status in the following order of importance:SO4 > N:S > S

N:P, N:K, and N:Mg ratios are more important than absolute levels of P, K, or Mg

Don’t be too concerned if possible deficiency is indicated for Cu, Zn, or Fe

Some basic interpretative rules

Confirm that standardized foliar sampling protocol was used

Assess foliar nutrient status within the context of site ecological characteristics

Confirm that N deficiency exists before assessing other nutrients

Assess S status in the following order of importance:SO4 > N:S > S

N:P, N:K, and N:Mg ratios are more important than absolute levels of P, K, or Mg

Don’t be too concerned if possible deficiency is indicated for Cu, Zn, or Fe

Ask for help if uncertain