Treesearch

Producing good quality seeds that perform well in the nursery continues to be challenging. High quality conifer seeds are obtained by optimizing collecting, processing, storing, and treating methodologies, and such quality is needed to consistently produce uniform nursery crops. Although new technologies are becoming available to evaluate seed quality, they have not been developed to the extent that they replace the more traditional methodologies developed over decades of trial and error. The most reliable approaches to predict nursery performance rely on obtaining high seed quality,...

Concentrations of methyl isothiocyanate (MITC) and chloropicrin (CP) in air spaces of nursery soil and in air at the soil surface following fumigation were determined in field trials in a Wisconsin and a Georgia nursery. MITC was measured in plots receiving either dazomet or co-application of metam sodium and chloropicrin; CP was measured in the latter plots. Soil surfaces were sealed with either a high density polyethylene tarp or by surface compaction and maintenance of a water seal following fumigation. Findings from the Wisconsin trial are highlighted. A very small percentage (< 3%) of...

The Hayward State Nursery, Wisconsin grows more than 40 species from seeds. Up to 6000 bushels of raw unprocessed tree and shrub seeds are collected each year, and all seeds are collected in Wisconsin or adjacent states. All white spruce (Picea glauca) and some white pine seeds (Pinus strobus) are collected from orchards containing genetically improved material.

Planting tree seeds at the Pennsylvania Department of Conservation and Natural Resources Penn Nursery, Spring Mills, Pennsylvania occurs in spring and fall. Seeds acquired for these plantings come from 3 sources. The first source is our own orchards, which were developed to provide “improved” seeds. Improved seeds are produced from scion material collected from trees selected for various characteristics and grafted onto rootstock. The second source is from general collections that are collected by forestry personnel from various forest districts.We have developed a barter system with these...

The New York State Department of Environmental Conservation Saratoga Tree Nursery maintains over 120 ha (300 ac) of seed orchard and seed production areas.With the help of New York State Corrections crews, cones and fruits of desired species are collected when ripe. Cones and fruits are transported back to the nursery, assigned a seedlot number according to species, stored on drying racks for about 3 months, and processed in the seed extractory located at the facility. All corresponding data is recorded for each seedlot; all germination tests are performed by nursery staff.

(Please note, this is an extended abstract only) Woodlands of pinon (Pinus edulis) and oneseed juniper (Juniperus monosperma) in the Jemez Mountains at Bandelier National Monument in northern New Mexico exhibit greatly accelerated rates of soil erosion, triggered by historic land use practices (livestock grazing and fire suppression). This erosion is degrading these woodland ecosystems and damaging thousands of archaeological sites in this national park unit, with similar patterns evident in woodlands across much of the Jemez Mountains.

Pinon-juniper woodlands in the southwestern United States (Arizona and New Mexico) represent approximately 54,000 square miles, equivalent to roughly 20% of the land base for the two states. Within this broad habitat type, there is a high degree of variability of vegetation in terms of species composition, their relative abundance, percent canopy cover, and typically inverse percentages of associated mixed shrub and herbaceous ground cover. This variation is explained by climate, soil type, elevation, slope, aspect, interspecies competition, and past anthropogenic activities. Another...

(Please note, this is an abstract only) New Mexico was historically grazed by many native and introduced ungulates, often called wildlife. Their distribution was limited especially in deserts until domestic animals were introduced and drinking water was provided. Plants respond to grazing with little resistance (black grama), to great resistance (blue grama), and to being stimulated (antelope bitterbrush). A plant species such as blue grama may be in sod form when grazed heavily and in bunch form when grazed more judiciously. Grazing and trampling that reduces plant cover and volume affect...

A complex of drought, insects, and disease caused widespread mortality in the pinyon-juniper forest types of the American Southwest in recent years. Most public and scientific attention has been given to the extent of drought-related mortality and causal factors. At the same time, there has been relatively little attention given to non-lethal drought effects. As part of standard data collection protocol, the Interior West Forest Inventory and Analysis program measures radial increment on a portion of tally tree species. Between 1981 and 2005, data were collected on 14,929 plots with pinyon...

Pinon-juniper vegetation is conspicuous in foothills surrounding most mountain ranges in the Great Basin and the Southwest. Utah has the largest percentage of pinon-juniper vegetation, followed by New Mexico, Nevada, Arizona, and Colorado. Although pinon-juniper stands may appear to be similar, the vegetation component varies. The most abundant junipers are Juniperus deppeana, J. monosperma, J. osteosperma, and J. scopulorum. The pinons are Pinus edulis in the Southwest and P. monophylla in the Great Basin. At most locations the tree layer has 1 to 3 species while the understory is also...