The lengthy time periods required by current spalting methods prohibit the economically viable commercialization of spalted wood on a large scale. This work aimed to compare the effects of induced spalting in 16 Pacific Northwest woods using three common spalting fungi, Chlorociboria aeruginosa, Scytalidium cuboideum, and Scytalidium ganodermophthorum, with the significantly less time-consuming treatment of these woods using dichloromethane-extracted green, red, and yellow pigments from the same fungi. For pigment extracts, the dosage required for a pigment to internally color various wood species to 30% internal coverage was investigated. With few exceptions, treatment with pigment extracts outperformed induced spalting in terms of percent internal color coverage. Cottonwood consistently performed best with all three pigment solutions, although chinkapin performed as well as cottonwood with the red pigment, and Port Orford cedar performed as well with the yellow pigment. While no wood species showed 30% internal color coverage with the green pigment solution, a number of additional species, including pacific silver fir, madrone, dogwood, and mountain hemlock showed internal color coverage on the order of 20–30% for red and/or yellow. Cottonwood was determined to be the best suited wood species for this type of spalting application. 1. Introduction Spalting refers to color changes in wood as a result of penetrating fungal colonization. Spalted wood has a long history of use in woodcraft and art, dating back at least as far as the 15th century [1], and attempts at inducing spalting in clear wood have been under scientific investigation since the mid-1800s [2]. Spalting is of particular value to the woodworking community due to the unique visual nature of the wood and is of growing interest to companies who seek a method of mass production so that spalted wood can be made readily available to those who utilize it. Unfortunately, although substantial early research was conducted on the pigmenting ascomycetes responsible for spalting [2–9], late 20th and early 21st century spalting research has focused almost entirely on the induction of melanized zone line-type spalting, with little regard to the more brightly colored fungal pigments [10]. Recent investigations into the induced spalting of wood, whether to achieve zone lines or pigmentation, has relied entirely on live fungal culture inoculations. In these methods, either small pieces of sterilized wood [11] or larger pieces of freshly cut wood [12] are inoculated with actively growing malt agar cultures
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