Treesearch

The willingness to accept - willingness to pay disparity raises questions about accepted economic theory. Plott and Zeiler (2005) have suggested that the disparity is the result of subject misconception about experimental procedures and, in an experiment designed to control for subject misconception, they show that the disparity can be turned on and off. This paper investigates a single feature of their experimental procedure - the prompt for subjects to consider revising their offers. Using the post-prompt and revision offers, we, like Plott and Zeiler, are unable to reject equality...

Scarification with boiling water plus stratification was most effective in improving germination of Iliamna rivularis (Douglas ex Hook.) Greene (Malvaceae) in an experiment that compared 3 treatments. Seeds from 15 sites representing 5 western US states were used in the experiment. Initial response of the seedlots to the treatments was similar, apart from one seedlot. The control treatment (intact seeds) yielded poor germination (1.8%). Mechanical scarification (part of the seedcoat removed) improved germination (average germination 49%), but not as much as the combination of boiling the...

The biology, recognition, and impact of eriophyid mites (with emphasis on species associated with trees and shrubs) are briefly reviewed. A case study of a leaf-curling eriophyid mite (Aceria sp.) attacking New Mexico olive (Forestiera pubescens Nutt. var. pubescens) is used to illustrate the complexities of developing control strategies for eriophyids in native plant nurseries. The effect of different acaricide treatments at various spray intervals are reported.

Red elm (Ulmus rubra), gray alder (Alnus incana), and buffaloberry (Shepherdia canadensis) are considered important plants for many Native American tribes in the United States. Native Americans use these 3 species for a variety of traditional and medicinal purposes. For example, red elm is still the preferred firewood for the cultural ceremonies of several tribes. Kansas tribal leaders would like to plant more of these species on tribal land, but they have been difficult to germinate due to seed dormancy mechanisms. While red elm is valued as a ceremonial tree, it is susceptible to Dutch...

Fuel reduction treatments around pinyon pine trees began as a simple project but ended in something more complex, enjoyable, and rewarding. The project eventually led to pinyon species (Pinus monophylla and P. quadrifolia) reforestation efforts, something that has been tried in the past with disappointing results. The Perry Pinyon Pines Protection Project and current efforts at propagation are described for areas on the San Jacinto Ranger District, San Bernardino National Forest, and on the Ramona and Santa Rosa Indian reservations. A greater measure of success in propagation of these...

The Tamarisk Coalition (TC), a nonprofit organization dedicated to riparian restoration in the western United States, has created a Native Plant Materials Program to address the identified need for native riparian plant species for use in revegetation efforts on the Colorado Plateau. The specific components of the Native Plant Materials Program include: 1) provide seed collection and riparian restoration training; 2) work with various partnerships and collaborators to help define needs/goals for active restoration; 3) help facilitate the development of appropriate replacement plant species...

This paper presents a summary of a research project designed to study the use of tree shelters as a means to provide initial shade for planted Engelmann spruce (Picea englemannii Parry ex Engelm.) seedlings on a reforestation site in southwestern Colorado where several past planting attempts had failed. Study results following 2, 6, and 11 growing seasons were formally published elsewhere. Four different shelter colors providing various shading levels and a control, consisting of shading using debris within the site, were included when the study was initiated in 1996. The darkest shelter...

To explore latitudinal genetic variation in cold hardiness and leaf phenology, we planted a common garden of paired collections of native and introduced riparian trees sampled along a latitudinal gradient. The garden in Fort Collins, Colorado (latitude 40.6°N), included 681 native plains cottonwood (Populus deltoides subsp. monilifera) and introduced saltcedar (Tamarix ramosissima, T. chinensis, and hybrids) collected from 15 sites from 29.2 to 47.6°N in the central United States. In the common garden, both species showed latitudinal variation in fall, but not spring, leaf phenology. This...

This article gives a brief history of the efforts of the Southern Forest Nursery Management Cooperative (SFNMC) in testing methyl bromide (MBr) alternatives for soil fumigation. In the southeastern United States, fumigation with MBr has been the most commonly used method for producing high quality, pest-free forest seedlings in an environment that is conducive for soil-borne pathogens, nematodes, and weeds. As a result of the Montreal Protocol, the production and use of MBr was to be incrementally phased out beginning in 2005. Included in this process are exemptions allowing for continued...

The importance of developing a market for quality native plant materials in a region prior to the establishment of a nursery is crucial to ensure its success. Certain tactics can be applied to help develop a demand for native plant materials in a region. Using these tactics will help create a new market for native plant materials.