Treesearch

I compared growth of container ponderosa pine (Pinus ponderosa) seedlings grown in a 1:1 (v:v) Sphagnum peat moss:coarse vermiculite medium (P:V) and a 7:3 (v:v) Sphagnum peat moss:Douglas-fir sawdust medium (P:S) at three different irrigation regimes. By using exponential fertilization techniques, I was able to supply seedlings with similar amounts of fertilizer over time even though irrigation frequency differed. Although I noted a reduced growth rate in P:S seedlings, final morphology was, for the most part, similar to their P:V cohorts. When given similar rates of fertilizer, seedlings...

Western Forest Systems, Incorporated (WFS) (Lewiston, ID) has been utilizing a peat/sawdust blended mix as our growing medium for the past 10 years. Our decision to change from a peat/vermiculite blend to a peat/Douglas-fir (Pseudotsuga menziesii) sawdust blend involved worker health and safety issues, seedling culture, seedling production, and economic impact.

In response to concerns regarding growing media substrate costs, and the impact of growing media on seedling quality, we evaluated three peat-based growing media substrates at the USDA Forest Service Coeur d'Alene Nursery in Idaho. Current medium consists of 80:20 peat:fresh Douglas-fir sawdust (v:v). Two other substrates, 75:25 peat:fine screened Douglas-fir bark (v:v) and 100% peat were explored as alternatives. Although sawdust and bark are currently sold at less than half the cost of peat, making them interesting alternatives from a financial basis, we found that western larch seedlings...

Pinon-juniper woodlands are an important vegetation type in the Great Basin. Old-growth and open shrub savanna woodlands have been present over much of the last several hundred years. Strong evidence indicates these woodlands have experienced significant tree infilling and major expansion in their distribution since the late 1800s by encroaching into surrounding landscapes once dominated by shrubs and herbaceous vegetation (fig. 1). Both infilling and expansion affects soil resources, plant community structure and composition, water and nutrient cycles, forage production, wildlife habitat,...

Wildland fires occur with increasing frequency in southwestern riparian forests, yet little is known about the effects of fire on populations of native and exotic vegetation. From 2003 to 2006, we monitored recovering woody vegetation in wildfire sites in the bosque (riparian forest) along the Middle Rio Grande of central New Mexico, USA. To examine recovery potential, we estimated densities of native Rio Grande cottonwood (Populus deltoides ssp. wislizenii) and exotic saltcedar (Tamarix ramosissima) in burned plots and estimated mortality rates of resprouts. Exotic vegetation density was...

As energy costs increase, resistance is strong to these costs becoming a larger proportion of production cost. Many options can be considered in this battle. This presentation deals only with altering thermostat settings during initial crop growth stages early in the season. Reducing energy requirements in greenhouse crop production while maintaining quality and on-time delivery is a challenge. Two concepts are discussed with respect to greenhouse heating set points: Q10 factors during seed germination and DIF during active growth.

In 2002, the USDA Forest Service Coeur d'Alene Nursery in Idaho began to evaluate ways to reduce energy consumption in lighting, refrigeration, and heating and cooling of facility workspace. The primary factor leading up to this was the inefficiency of the nursery's Freon(R)-based refrigeration system. Energy costs and maintenance of the system were becoming a larger portion of the nursery's operating budget. Through the Bonneville Power Administration (BPA), the nursery used third-party financing, financial incentives, and a design-build contract to accomplish the work with very little...

Depending on location and luck, natural gas rates have gone from less that CAN$ 3.00 to more than CAN$ 20.00/gigajoule (Gj). Natural gas rates are currently around CAN$ 13.00/Gj, although industry "analysts" predict an increase. A gigajoule is equivalent to the energy released by the combustion of approximately 30 L (8 gal) of gasoline. It is also equivalent to approximately 950,000 BTU, 0.165 barrels of oil, or 278 kilowatt-hours of electricity.

The Red Lake Tribal Forestry Greenhouse in Red Lake, MN, utilizes four types of outdoor furnaces for heating through the fall, winter, and spring. The WoodMaster® is a highly efficient, wood-fired furnace that provides forced-air heat to the greenhouse. The HeatmorTM furnace is an economical wood-fired alternative that can provide lower insurance rates due to the large number of safety features. The CharmasterTM is a combination wood and oil furnace that is used as a backup system when ambient temperatures reach -34 °C (-30 °F). The LennoxTM furnace is an oil-burning furnace that provides...

Geothermal energy is heat (thermal) derived from the earth (geo). The heat flows along a geothermal gradient from the center of the earth to the surface. Most of the heat arrives at the surface of the earth at temperatures too low for much use. However, plate tectonics ensure that some of the heat is concentrated at temperatures and depths favorable for its commercial extraction (fig. 1). The water may circulate to a depth of at least 4,270 m (14,000 ft). It is then heated and moves upward along fault zones and fractures.