Amanda M. Foust 1,2, William L. Headlee 1,2, Matthew G. Olson 1,2, and Shaik M.Y. Hossain 1,2

1 School of Forestry and Natural Resources, University of Arkansas at Monticello, Monticello, AR 71656, USA2Arkansas Forest Resources Center, University of Arkansas System Division of Agriculture, Monticello, AR 71656, USA

ABSTRACT

Cellulose has become an increasingly popular material in the biomedical and

engineering fields due to its strong and flexible nature, especially for emerging

nano-materials (e.g. filters with very small but precise pore sizes). With the

abundant timberland in the United States, trees would be a reliable feedstock

for nano-cellulose products. Thus, the purpose of this study was to evaluate

species differences and spacing effects on specific gravity, cellulose, and

lignin content to determine optimal species and planting conditions for

cellulose production. Cores were collected from 5 hardwood species at 2

planting spacings and analyzed for specific gravity, cellulose, and lignin & ash

content. Cherrybark, cow oak, and sweetgum had significantly higher

cellulose content than Nuttall and water oak. They also had lower lignin

content than water oak. As these 3 species did not significantly differ in their

cellulose and lignin content, they are all viable feedstock for nano-cellulose

production. Spacing had no significant effect on specific gravity, cellulose, or

lignin content. Future research should evaluate if these trends are consistent

across multiple planting conditions, geographic regions, and climatic

condition.

METHODS AND MATERIALS

Sample Collection:

• Tree cores were collected from 5 hardwood species at 2 spacings

(8’ x 8’ and 12’ x 12’)

Specific Gravity:

• Tree cores were dried at 65°C and weighed.

• Volume was calculated from core diameter and length measurements.

• Specific gravity = dry weight/ volume

Fiber Content:

• Cores were ground and analyzed for percent cellulose and lignin & ash

content using the ANKOM 2000 Automated Fiber Analyzer.

INTRODUCTION

Lightweight and stronger than steel, nano-cellulose has garnered much

attention for uses in the biomedical and biological engineering fields.

Potential uses for nano-cellulose include the manufacturing of selectively

permeable packaging for food storage and water filters. Because cellulose

naturally occurs in plant tissue, trees could prove to be viable source material

for the manufacturing needs of nano-cellulose products. The ideal source

material for cellulose would have high specify gravity and cellulose content,

while having low lignin content to expedite the cellulose extraction process.

The purpose of this study is to evaluate 5 different hardwood species at 2

planting spacings to determine the optimal species and planting conditions for

maximizing cellulose production.

• Species had a significant effect on specific gravity, cellulose, and

lignin & ash, while Spacing and Species × Spacing had no significant

effects.

• Cow oak had the highest specific gravity.

• Cherrybark, cow oak, and sweetgum had higher cellulose content than

Nuttall and water oak., and lower cellulose content than water oak.

• Cherrybark, cow oak, and sweetgum showed no significant

differences in cellulose and lignin & ash content.

RESULTS

Figure 2. ANOVA results of species specific gravity. Different letters

represent significant difference (P < 0.05).

Figure 3. ANOVA results of species cellulose content. Different letters

represent significant difference (P < 0.05).

Figure 4. ANOVA results of species lignin & ash content. Different

letters represent significant difference (P < 0.05).

CONCLUSIONS AND DISCUSSION

• Nuttall and water oak were the least favorable

species for cellulose production, with higher

lignin & ash and

lower cellulose content.

• Cherrybark, cow oak, and sweetgum are

all viable species for cellulose production

as there was no significant difference in cellulose

and lignin & ash content.

• Future work should evaluate if these trends

are consistent across various spacing treatments,

site locations, and climate conditions.

ACKNOWLEDGEMENTS

This work was supported in part by the USDA National Institute of Food and

Agriculture (McIntire Stennis project 1009221). Funding for this research was

provided by the Center for Advanced Surface Engineering, under the National

Science Foundation Grant No. OIA-1457888 and the Arkansas EPSCoR Program,

ASSET III. Additional support for this project was provided by Weyerhaeuser and

the UA Division of Agriculture’s Arkansas Forest Resource Center.

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Figure 1. (Left) Photo of study site established in 1976 as a hardwood spacing trial

near Monticello, AR. (Upper right) Example of tree cores collected from study trees.

(Lower right) ANKOM 2000 fiber analyzer used to characterize cellulose,

hemicellulose, and lignin + ash content.