Treesearch

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

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...

Incubating eggs of autumn-spawning Chinook salmon (Oncorhynchus tshawytscha) could be at risk of midwinter high flows and substrate scour in a changing climate. A high-spatial-resolution multidimensional hydrodynamics model was used to assess the degree of scour risk in low-gradient unconfined gravel bed channels that are the favored environment for autumn-spawning salmon in mountain watersheds such as the Middle Fork Salmon River (MFSR), Idaho. In one of the most important MFSR spawning tributaries, near-bed shear stresses were relatively low at all discharges from base flows to 300% of...

It is widely recognized that high supplies of fine sediment, largely sand, can negatively impact the aquatic habitat quality of gravel-bed rivers, but effects of the style of input (chronic vs. pulsed) have not been examined quantitatively. We hypothesize that a continuous (i.e. chronic) supply of sand will be more detrimental to the quality of aquatic habitat than an instantaneous sand pulse equal to the integrated volume of the chronic supply. We investigate this issue by applying a two-dimensional numerical model to a 1 km long reach of prime salmonid spawning habitat in central Idaho....

These proceedings are a compilation of 20 papers that were presented at the regional meetings of the forest and conservation nursery associations and the Intertribal Nursery Council meeting in the United States in 2012. The Joint Meeting of the Southern Forest Nursery Association and Northeastern Forest and Conservation Nursery Association was held at the Sheraton Read House Hotel, Chattanooga, TN, July 16 to 19, 2012. Subject matter for the technical sessions included southern nursery history, nursery insect and disease management, water quality, chilling hour review, root architecture,...

The harvest of non-timber forest products (NTFP) for personal uses such as hobbies and handicrafts, cooking and canning, and recreation is an important pursuit for many residents in Alaska (Pilz and others 2006). Five categories of NTFP have been designated by the United Nations Food and Agricultural Organization: (1) foods; (2) medicinal plants; (3) floral greenery and horticulture products; (4) fiber and dye plants, lichens, and fungi; and (5) oils, resins, and chemicals extracted from plants, lichens, and fungi (McLain and Jones 2002). As noted by Alexander and others (2002), interest...

Over the past 50 years, Colorado has experienced an increase in the number and size of wildfires on its public and private lands. Nationwide, expenditures on wildfire suppression have increased for decades and now are measured in the billions of tax dollars. Current trends in climate changes, fuel accumulation from past wildfire suppression, and expansion of the wildland-urban interface (WUI), which means more development within areas of heightened wildfire potential, all suggest that continued increases in the costs of wildfires are likely.