Excel Erosion Education Circular, Volume - 2 The Excelsior Advantage
E3C Volume 2 - Benefits of Advantages of Excelsior Fibers Excelsior ECBs
E3C is produced by Western Excelsior to provide accessible, reliable education regarding erosion control and Rolled Erosion Control Products (RECPs). E3C covers an array of topics critical to the RECP industry today. Volume 2 focuses on temporary excelsior blankets and presents the advantages of utilizing excelsior fibers in contrast to other matrix components.
The Excelsior Story
Utilization of manufactured excelsior fibers to control erosion is one of the longest standing Best Management Practices (BMPs). Excelsior is a machine produced wood fiber, manufactured by shaving aspen or poplar trees. The trees must be debarked and dried and processed to ensure the proper moisture content, length, strength and interlocking of the fiber. Trees harvested for production of Excelsior are typically from over-grown forests that require fuel reduction for safety. The resultant fibers are durable and strong, forming a matrix that is lofty, open, interlocking and stable; ideal for resisting the forces of rainfall or flowing water and establishing vegetation.
Advantages of Excelsior Fibers
Excelsior fibers are produced under a controlled and specified manufacturing process. Thus, fiber diameter, length, strength and moisture content are consistent and controlled at the time of manufacture. Since the fiber dimensions are controlled, the resultant excelsior matrix of the ECB is more consistent in coverage and thickness, compared to straw and coconut/straw blankets. Additionally, aspen fibers are naturally more resistant to degradation than straw fibers. In particular, high altitude Rocky Mountain aspen trees yield excelsior fibers of the highest quality with superior strength, durability, water holding capacity and lighter weight. The advantages of the excelsior fiber, manufactured into a very consistent, open, lofty matrix, yields the highest performing temporary ECBs available.
Performance of ECBs includes reducing erosion on hillslopes and in channels and increasing vegetation establishment rates. Excelsior ECBs provide performance for all three requirements and reduce "tenting" of the material, a function of the open matrix. Excelsior ECBs also function to significantly increase and hold soil moisture, compared to unprotected conditions.
Quantification of the utility of ECBs is achieved by performance testing. For protecting slopes from rainfall, performance is measured by proportional reduction of erosion, compared to identical control plot. For use as a flexible channel liner, the maximum, permissible shear stress of the material quantifies the performance. The material with the highest shear stress is the highest performing material. Finally, the ability to enhance the establishment of vegetation is considered a performance parameter. Figures 1 through 4 present plots of comparative excelsior product performance.
The principle factor contributing to the superior performance of excelsior fiber as an ECB matrix is manufactured quality control. Straw and coconut fibers are harvested or imported and cannot be intensely scrutinized, similar to manufactured fibers. Consistent fiber dimensions yield consistent matrix coverage, and thus, consistent quality and performance. The performance benefit is apparent in Figures 1 through 4.
Western Excelsior manufactures seven excelsior ECBs intended to provide a wide range of options. With rapid degradable, 100% biodegradable, temporary, heavy duty, single net and double net options, the Excel line of excelsior ECBs offer solutions to a wide variety of erosion challenges. Additionally, all Excel products are laboratory tested and field proven for reliable performance. Western Excelsior also provides industry leading quality control and product warranty. Finally, Excel Erosion Design (available at www.westernexeelsior. com) utilizes state of the practice design methods to aid in implementation of Excel ECBs. Considering its origin as logging to reduce forest fire fuel and superior performance, utilizing excelsior for erosion control is truly "Blanketing Nature with Nature".