session 13 ic2011 mc connell

WETTABILITY OF SOUTHERN PINE

SUBJECTED TO BARK BEETLE

FUNGAL ASSOCIATES

By

Eric McConnell, Nathan Little, Nate Irby,

John Riggins, and Sheldon Shi

Forest Products Society, Portland OR

Primary Species of the Southern Pine Bark Beetle Guild

3 species of Ips

Black Turpentine Beetle (D. terebrans)

Southern Pine Beetle (D. frontalis)

Southern Pine Beetle

(D. frontalis)

• Last Major Outbreak in

South ~10 years ago

• $1 billion in damages

• Environmental and social

impacts as well

• Initially overcomes

oloeresin

• Inoculating a variety of

fungi

• O. minus most prolific

early

• Death occurs through

many factors

– Gallery and fungal

proliferation

• Timely salvaging can

produce lumber

– LRF

– Grade

• Decay fungi and

termites soon after

What About Composites?

• Kelly et al (1982)

utilized SPB-killed trees

in mixture with healthy

• MOR, IB, & SW

• 2 & 24 hour

TS & WA

• No proposed

explanation

What About Composites?

• Adhesive must

adequately penetrate for

effective bonding

• Wicking occurs via

capillary forces

• Provides intimate

contact

• Better understanding

resin-wood interface

may provide economic

uses for biologically

attacked timber

• MS overdue for an

outbreak

Goals

• Determine DCA of

– Green and Kiln-dried SYP

– With and without blue

stain present

– Wilhelmy Plate

• Calculate surface energy

– Geometric mean

Avg. Dynamic Contact Angles

Probe Liquid [Surface tension]

Water

[72.8 mJ/M2]

α-

Bromonapthalene

[44.4 mJ/M2]

Formamide

[58.0 mJ/M2]

Ethylene Glycol

[48.0 mJ/M2]

Wood Type Average contact angle (standard deviation)

Green SPB

blue-stain51.1 (2.6) 29.4 (3.5) 52.7 (1.5) 41.4 (1.6)

Kiln-dried

control45.4 (4.1) 9.4 (9.1) 45.1 (2.6) 42.0 (1.7)

Green

control47.0 (8.3) 16.1 (11.5) 42.8 (10.5) 39.3 (3.0)

Kiln-dried

blue-stain0.0 (0.0) 0.0 (0.0) 52.8 (0.3) 34.4 (4.6)

Geometric Mean

d

L

p

Lp

S

d

Sd

L

L

5.0

*

*2

*)cos1( 5.05.0

5.0 )()(

xY 1

Surface Energies

TreatmentDispersive

forces

Polar

forces

Total surface

energy

Green

SPB blue-stain28.42 17.92 46.34

Kiln-dried control 31.37 18.84 50.21

Green control 31.86 18.40 50.26

Kiln-dried blue-stain 25.03 34.46 59.49

• Once beetle attack

occurs, various changes

take place

– Anatomical

– Morphological

– Chemical

– Physical

• All affect surface

energy

• O. minus initially

confined to ray

parenchyma in sapwood

• Cause water-conducting

blockages through

internal wounding

• Resin formation results

to slow fungal spread

• Subsequent penetration

of tracheids results in

movement across cells

via pit pairs

• Permeability

• “Stained” areas suffer

moisture loss

• Increased permeability would allow for

increase liquid transport across the grain

• KD/BS wood would have had a greater degree

of fluid flow in 3 directions

• Chemicals from tree’s wound response may

have disrupted liquid movement in Gr/BS

wood

• One possible mechanism

described for improving

board properties

• Future studies

– Other processes

– Various sized wood

elements

Conclusions

• Little change in non-

stained wood following

drying

• KD/BS wood surface

energy higher than

others

– >15% over each wood

type

Conclusions

• Wound response

possibly contributed to

lower surface energy in

Gr/BS wood

• BS wood from beetle-

killed trees may yield

properties for wood

composites

• Timely utilization is key

Thank You

For More Information

nathanlittle.msu@gmail.com

mcconnell.213@osu.edu