Abstract

Pine bark (PB) for horticultural uses is becoming less available and as a result, there is a need to develop alternative substrates for continued profitability of the nursery industry. This study, conducted at Poplarville, MS, and Auburn, AL, evaluated the growth of nine perennial species in a substrate composed of a pulpwood harvesting by-product called clean chip residual (CCR) which contains approximately 50% wood fiber. Two CCR particle sizes were used alone or amended with peat moss (PM) (4:1 by vol) and compared with control treatments PB and PB:PM. Substrates composed of 100% PB or 100% CCR had high air space (AS) and low water holding capacity (WHC) which resulted in less available water to plants. Addition of PM lowered AS and increased WHC. There were no significant differences among growth indices at Poplarville for 6 of 8 species and for 3 of 7 species at Auburn, though the remaining 4 species were only slightly smaller when grown in 100% CCR. Shoot dry weight was greatest in substrates amended with PM. Results of this study indicate that acceptable growth of perennial plants can be obtained in substrates composed of CCR when compared to PB and PB amended with PM.