This document summarizes a study that applied nitrogen, phosphorus, and calcium treatments to northern hardwood forest stands and analyzed the effects on foliar nutrients and gas exchange. Key findings include: 1) Nitrogen and phosphorus treatments only increased foliar levels of the corresponding nutrients in one of the five stands. 2) Calcium addition increased foliar manganese levels in three of the five stands. 3) Calcium silicate addition increased foliar silicon levels in sugar maple, American beech, and yellow birch trees in all stands studied. 4) The calcium silicate treatment did not have significant effects on photosynthesis or stomatal conductance in the tree species analyzed.

1. Multiple Element Limitation in
Northern Hardwood Ecosystems
(MELNHE)
Foliar Nutrients 2013
Adam Wild
Ruth Yanai
SUNY ESF

2. Nitrogen: 30 kg N/ha/yr as
NH4NO3
Phosphorus: 10 kg P/ha/yr as
NaH2PO4
-Applied twice in 2011, 2012 &
2013
Calcium: 1150 kg Ca/ha/yr as
Wollastonite (CaSiO3)
-Applied once in fall 2011
Treatment Design &
Application Rate

3. Foliar Nutrient Methods
• Leaves were shot 7/24/13-7/27/13
in 5 stands: C6, C8, C9, JBm & JBo.
• We sampled 4 sugar maple trees in
each plot. These were the 2 trees
with the sweetest sap and 2 trees with the
least sweet sap in each plot.
• In addition, 3 yellow birch and 3 American
beech trees were sampled in C8 control and
Ca plots.
• Daniel Conley and Wim Clymans analyzed Si.
Adam analyzed N, P, Ca, Mg, Mn, and K at ESF.
3

4. Gas Exchange Methods
4
• We tested for treatment effects with CRD
ANOVA within stands for each nutrient.
Tukey’s differences are reported for α = 0.10.
Statistical Analysis
• 1 healthy leaf sample from each tree
• LI-COR 6400 XT
• Potential photosynthesis & stomata
conductance
-Thanks to Heidi Asbjornsen &
Katherine Sinacore

5. C6 C8 C9 JBM JBO
p=0.08p=0.03p=0.60p=0.14p=0.35
b
a ab
ab
ab
a
b
ab
ab
a
a
a
a
a
a
a
a
a
a
a
a
N treatment resulted in higher foliar N only at Jeffers Brook.

6. C6 C8 C9 JBM JBO
p=0.04p=0.006p=0.21p=0.23p=0.93
b
ab
ab
a
a
a
ab
c
bc
bc
a
a
a
a
a
a
a
a
a
a
a
P treatment resulted in higher foliar P only at Jeffers Brook.

7. C6 C8 C9 JBM JBO
p=0.06p=0.93p=0.83p=0.01p=0.55
ab
a
ab
ab
b
a
a
a
a
a
a a
a
a
a
ab
cabc bc
a
a
There were some significant treatment effects on foliar K but they were not consistent.

8. C6 C8 C9 JBM JBO
p=0.18p=0.59p=0.39p=0.12p=0.41
a a
a
a
a
a
a
a
a
a a
a a
a
a
a
a
a
a
a
a
There were no treatment effects on foliar Mg.

9. C6 C8 C9 JBM JBO
p=0.006p=0.02p=0.21p<0.001p=0.01
a
ab
b
b
b
a
b
ab ab
ab
a
a
a
a
a
ab
bc
c
c
a
b
Ca addition increased foliar Mn in C6, C8, and JBo.

10. C6 C8 C9 JBM JBO
p=0.07
a
a
a
a
a
p=0.7p=0.63p=0.06p=0.99
a
a
a
a
a
a
a
a
a
a
a
a
aa
a
There were no treatment effects on foliar Ca.

11. sugar maple
A. beech yellow birch
p=0.001 p=0.001 p=0.01 p=0.02p=0.07 p=0.002
b
a
b
a
b
a
b
a
b
a
b
a
The CaSiO3 addition increased foliar Si in all six stands.

12. p=0.15 p=0.74p=0.64
C8 Beech C8 Yellow
Birch
Sugar Maple
p=0.06p=0.50p=0.12
Photosynthesis of Control and CaSiO3 Addition Trees

13. p=0.15 p=0.05p=0.28
C8 Beech C8 Yellow
Birch
Sugar Maple
p=0.58p=0.10 p=0.31