Effect of burgundy solid extracted from Eastern Red Cedar heartwood on subterranean termites and wood-decay fungi

Authors: Eller, Fred; Kirker, Grant; MANKOWSKI, M - Forest Products Laboratory; Hay, William; Palmquist, Debra

Submitted to: Industrial Crops and Products
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/29/2019
Publication Date: 2/14/2020
Citation: Eller, F.J., Kirker, G.T., Mankowski, M.E., Hay, W.T., Palmquist, D.E. 2020. Effect of burgundy solid extracted from Eastern Red Cedar heartwood on subterranean termites and wood-decay fungi. Industrial Crops and Products. 144:112023. https://doi.org/10.1016/j.indcrop.2019.112023.
DOI: https://doi.org/10.1016/j.indcrop.2019.112023

Interpretive Summary: This research determined that a burgundy-colored material from Eastern red cedar wood has significant wood preservation properties against termites and some wood decay fungi. Eastern red cedars are an abundant natural resource in the U.S. and they are the domestic source of cedarwood oil. The reddish heartwood is resistant to attack by termites and wood decay fungi. The heartwood contains both cedarwood oil and burgundy compounds that can be extracted and used for a variety of purposes. The isolated burgundy-colored material had a minor inhibitory effect on termites and one of the white-rot decay fungi tested. However, it did not inhibit either of two brown-rot fungi tested nor the other white-rot fungi tested. Wood treated with a combination of the burgundy-colored material, cedarwood oil and a starch derivative resulted in the highest termite mortality, lowest percentage wood mass loss for the termites and lowest percentage wood mass losses all four species of wood decay fungi studied. These results demonstrate that the natural burgundy material and cedarwood oil from abundant Eastern red cedar could be used to treat wood and help protect wood from termites and wood decay fungi.

Technical Abstract: Eastern red cedar (ERC) is an abundant natural resource in the U.S. and has been investigated for the extraction of cedarwood oil (CWO) and CWO bioactivity, particularly its use to protect wood against termites and decay fungi. Methanol extraction of ERC sawdust gives a burgundy-colored oil (BO) that is comprised of both CWO and a burgundy solid (BS). Prior research indicated the BS itself might have inhibitory bioactivity. This study investigated the wood preservation properties of the BS alone, in combination with CWO and in conjunction with an amylose inclusion complex (AIC) against termites, brown-rot decay fungi and white-rot decay fungi. Wood was treated by vacuum/pressure impregnation and tested for resistance to subterranean termites and four species of decay fungi. The AIC alone made wood less palatable and more toxic to termites but did not inhibit either brown-rot fungi nor the white-rot Trametes versicolor but did inhibit the white-rot Irpex lacteus. The CWO led to both lower wood mass loss by termites and higher termite mortality as well as having an inhibitory effect on the white-rot decay fungi. However, a combination of AIC and CWO was necessary to have an inhibitory effect on the brown-rot fungi. The BS had a minor inhibitory effect on termites but did not inhibit either brown-rot fungi nor the white-rot I. lacteus. The BS did, however, inhibit the white-rot T. versicolor. Wood blocks vacuum/pressure impregnated with the combination of the AIC, CWO and BS resulted in the highest termite mortality, lowest percentage wood mass loss for the termites and lowest percentage wood mass losses all four species of wood decay fungi studied.