Treesearch

Longleaf pine (Pinus palustris Mill.) seedlings cultured in four cavity volumes (60 to 336 ml [3.7 to 20.5 cubic inches]), two root pruning treatments (with or without copper coating), and 3 nitrogen levels (low to high) were grown for 29 weeks before they were outplanted into an open area in central Louisiana. Twenty-two months after outplanting, 3 seedlings were excavated from each of the 24 treatment combinations to evaluate effects of nursery cultural treatments on seedling growth and root system architecture. This paper reports some preliminary observations from that sample. Seedlings...

This paper summarizes ten of the biggest “pitfalls” or challenges I have encountered in my experience growing southern pine seedlings in containers over the past 30 years. Learning from challenges is an important part of growing successful nursery operations.

High substrate pH is a major problem for producers of container-grown plants and seedlings. The primary cause of high substrate pH is irrigation water with high alkalinity. Alkalinity is defined as the capacity of water to neutralize acids. Some alkalinity in irrigation water is beneficial as it serves as a buffer to large swings in pH levels, but high alkalinity in the water often leads to micronutrient deficiencies. Alkalinity of irrigation water should be monitored for changes on a regular basis. Be sure to check with the laboratory being used to determine if they test for alkalinity,...

This paper is a critical review of over four decades of research on chilling with southern pine seedlings. For most pines, freeze tolerance, seed dormancy, and endodormancy of terminal buds are affected by natural chilling (0° to 8 °C [32 to 46 °F]). Unfortunately, in the field of reforestation, several myths have emerged regarding the importance of chilling. One myth is that chilling seedlings in a dark cooler will increase freeze tolerance of southern pine seedlings and another myth states that chilling must occur before pine seedlings can be successfully “hot-planted.” I once believed...

Laboratory and field trials have shown Proline® (prothioconazole) to be efficacious against the causal agent of Rhizoctonia foliar blight on loblolly pine (Pinus taeda). A biweekly application of Proline ® at 5 fl oz/ac in nursery field tests significantly reduced Rhizoctonia foliar blight on loblolly pine when compared to applications of Abound ® azoxystrobin (24 fl oz/ac; 1 fl oz/ac = 73.1 ml/ hectare) and the non-treated control. The potential monetary loss due to Rhizoctonia foliar blight per acre was $967 for non-treated, $209 for azoxystrobin treated, and

We produced defect-free electrospun fibers from aqueous dispersions of lignin, poly(vinyl alcohol) (PVA), and cellulose nanocrystals (CNCs), which were used as reinforcing nanoparticles. The thermomechanical performance of the lignin-based electrospun fibers and the spin-coated thin films was improved when they were embedded with CNCs. Isochronal dynamic mechanical analysis (DMA) was used to assess the viscoelastic properties of the lignin:PVA electrospun fiber mats loaded with CNCs. DMA revealed that α relaxation processes became less prominent with an increased lignin content, an effect...

The objectives of this study were to investigate the effect of seasonal temperature changes on acoustic velocity measured on standing trees and green logs and to develop models for compensating temperature differences because acoustic measurements are performed in different climates and seasons. Field testing was conducted on 20 red pine (Pinus resinosa) trees and 10 freshly cut red pine logs at a 45-yr-old plantation stand in Arena, WI. Acoustic velocities of the red pine trees and logs and the ambient temperatures were monitored for 12 consecutive months. Results indicated that ambient...

The dry mixed-conifer forests that cover millions of acres in 12 western states experience low- to mixed-severity fire regimes; are typically heterogeneous in species composition, forest structure, and fuel dynamics; and grow quickly enough to generate concern about fuel treatment longevity. Yet compared to stands of pure ponderosa pine, there has been little research on fuel treatment effectiveness and economics in these forests.

A research silviculturist's work is firmly grounded in the scientific method to acquire knowledge on forest dynamics. They also integrate information from numerous sources to produce new knowledge not readily identified by single studies. Results and interpretation subsequently provide the scientific foundation for developing management decisions and strategies. The results from scientific investigations are documented in manuscripts, monographs, and reports. The art of silviculture is developed through talent, curiosity, and personal experience, and from a crossgenerational connection...

Understanding the factors regulating the composition and abundance of natural regeneration in forest ecosystems is critical to sustainable management worldwide. Using a long-term silvicultural experiment in Maine, we partitioned the variation in natural regeneration and examined the contribution of overstory and understory vegetation (biotic factors), substrate and soil attributes (abiotic factors), and silvicultural treatment. We hypothesized that silvicultural treatment (single-tree selection with 5, 10, and 20-year cutting cycles and diameter-limit cutting) would be less influential...