Treesearch

The target Douglas-fir seedling for outplanting on Roseburg Resources Company timberlands is a least-cost, large [stem] caliper 1- to 2-year old bareroot (>8 mm) or container (>6 mm) seedling with good form, high root growth potential, and the ability to withstand browse without the use of browse deterrents. This target is achieved through the use of large cell transplant plugs and low density spring or fall transplanting, or large cell low density container seedlings for outplanting.

Work has been initiated to restore native vegetation on the soil and base gravel layers that were once underneath constructed facilities at the Umatilla Chemical Depot (UMCD) in eastern Oregon. Propagules were collected from native plant species found around the UMCD. Germination success ranged from 0% to 75% for the species tested. Ten species were successfully propagated in sufficient numbers to use in an outplanting study to monitor species survival. After three growing seasons, survival ranged from 100% for Opuntia polycantha (pricklypear) to 5.6% for Lupinus sericeus (silky lupine)...

Welcome to the fifth issue of the Rocky Mountain Research Station's (RMRS) Invasive Species Science Update. The newsletter is produced by the RMRS Invasive Species Working Group (ISWG), which is a core group of scientists who volunteer to coordinate outreach of RMRS invasive species science to managers and the public. After publishing the past four newsletters, we've concluded that an annual issue will best represent the pace of new science and keep users abreast of the latest research. Subsequent issues will occur each fall. The ISWG also disperses its recent research findings through...

The role of high quality seeds in producing target seedlings is reviewed. Basic seed handling and upgrading techniques are summarized. Current advances in seed science and technology as well as those on the horizon are discussed.

Morphology is classically defined as the form and structure of individual organisms, as distinct from their anatomy or physiology. We use morphological targets in the nursery because they are easy to measure, and because we can often quantitatively link seedling morphological traits with survival and growth performance in the field. In the 20 years since the Target Seedling Concept was developed, morphological targets remain some of the most commonly used attributes to link seedling quality and field performance. Traits such as height and root-collar diameter are still standard attributes,...

Roots are critical to seedling performance after outplanting. Although root quality is not as quick and simple to measure as shoot quality, target root characteristics should be included in any seedling quality assessment program. This paper provides a brief review of root characteristics most commonly targeted for operational seedling production. These are: root mass (with special attention to shoot:root), root fibrosity, root length, root form, and root growth potential.

Planting failures are often attributed to unexpectedly harsh conditions after planting. Characterization of soil water at the planting site, along with associated influences of site preparation and soil texture, is recommended. Additionally, tree planting technique and seedling biology should be targeted to site conditions. A nursery regime for induction of drought hardening is proposed for hot-lift summer- and fall-planted container conifers.

Plants have the marvelous ability to take up inorganic mineral nutrients as atoms or simple molecules and process them into proteins, enzymes, and other organic forms. This paper reviews the 14 essential mineral nutrients, their roles within the plant, their target concentrations in tree seedling nursery culture, and their effects on seedling growth and performance after planting. Three areas of active research in tree nutrition over the past 20 years with relevance to the Pacific Northwest are discussed: steady state nutrition, exponential fertilization and nutrient loading; adaptation to...

Water management is one of the most important factors in achieving the target seedling. Water is required for cell growth, nutrient transport, cooling through transpiration, and in small amounts for the photosynthetic reaction. Furthermore, judicious use of limiting water availability during the hardening phase can induce budset and increase seedling cold hardiness. Nursery managers typically measure seedling moisture status with the pressure chamber and medium water status using the block weight method. Newer soil moisture sensors, such as time domain reflectometry (TDR) units, offer...

Subalpine fir (Abies lasiocarpa [Hook] Nutt.) is a wide-ranging, high-elevation species in the interior of British Columbia. It is commonly harvested for lumber, but replanting of it is limited. Some reticence is based upon wood quality and rate of growth, but there are also seed and nursery culturing difficulties. This study investigated seedling growth traits of 111 provenances grown in four nurseries. Considerable variation in growth potential was found. The strength of nursery effects and correlations of nursery height to height growth at 5 years in the field are reported. Recommendatio...