Frost is a thin layer of ice on a solid surface, which forms from water vapor in an above freezing atmosphere coming in contact with a solid surface whose temperature is below freezing, and resulting in a phase change from water vapor to ice as the water vapor reaches the freezing point. In temperate climates, it most commonly appears on surfaces near the ground as fragile white crystals; in cold climates, it occurs in a greater variety of forms. The propagation of crystal formation occurs by the process of nucleation.
Taiga, also known as boreal forest or snow forest, is a biome characterized by coniferous forests consisting mostly of pines, spruces, and larches.
A plum is a fruit of the subgenus Prunus of the genus Prunus. The subgenus is distinguished from other subgenera in the shoots having terminal bud and solitary side buds, the flowers in groups of one to five together on short stems, and the fruit having a groove running down one side and a smooth stone.
Fruit tree pruning is the cutting and removing of selected parts of a fruit tree. It spans a number of horticultural techniques. Pruning often means cutting branches back, sometimes removing smaller limbs entirely. It may also mean removal of young shoots, buds, and leaves.
A winter storm is an event in which varieties of precipitation are formed that only occur at low temperatures, such as snow or sleet, or a rainstorm where ground temperatures are low enough to allow ice to form. In temperate continental climates, these storms are not necessarily restricted to the winter season, but may occur in the late autumn and early spring as well. Very rarely, they may form in summer, though it would have to be an abnormally cold summer, such as the summer of 1816 in the Northeastern United States.
Picea mariana, the black spruce, is a North American species of spruce tree in the pine family. It is widespread across Canada, found in all 10 provinces and all 3 Arctic territories. Its range extends into northern parts of the United States: in Alaska, the Great Lakes region, and the upper Northeast. It is a frequent part of the biome known as taiga or boreal forest.
A nursery is a place where plants are propagated and grown to usable size. They include retail nurseries which sell to the general public, wholesale nurseries which sell only to businesses such as other nurseries and to commercial gardeners, and private nurseries which supply the needs of institutions or private estates.
Silviculture is the practice of controlling the growth, composition, health, and quality of forests to meet diverse needs and values.
Alpine plants are plants that grow in an alpine climate, which occurs at high elevation and above the tree line. There are many different plant species and taxon that grow as a plant community in these alpine tundra. These include perennial grasses, sedges, forbs, cushion plants, mosses, and lichens. Alpine plants are adapted to the harsh conditions of the alpine environment, which include low temperatures, dryness, ultraviolet radiation, and a short growing season.
Girdling, also called ring-barking is the complete removal of a strip of bark from around the entire circumference of either a branch or trunk of a woody plant. Girdling results in the death of the area above the girdle over time. A branch completely girdled will fail and when the main trunk of a tree is girdled, the entire tree will die, if it cannot regrow from above to bridge the wound. Animals such as rodents, will girdle trees by feeding on outer bark often during winter under snow. Human practices of girdling including forestry, horticulture, and vandalism. Foresters use the practice of girdling to thin forests. Girdling can also be caused by herbivorous mammals feeding on plant bark and by birds and insects, both of which can effectively girdle a tree by boring rows of adjacent holes.
Grape black rot is a fungal disease caused by an ascomycetous fungus, Guignardia bidwellii, that attacks grape vines during hot and humid weather. “Grape black rot originated in eastern North America, but now occurs in portions of Europe, South America, and Asia. It can cause complete crop loss in warm, humid climates, but is virtually unknown in regions with arid summers.” 4 The name comes from the black fringe that borders growing brown patches on the leaves. The disease also attacks other parts of the plant,“all green parts of the vine: the shoots, leaf and fruit stems, tendrils, and fruit. The most damaging effect is to the fruit”. 3
Bear Rocks are a widely recognized symbol of West Virginia wilderness and among the most frequently photographed places in the state. They are a well-known landmark on the eastern edge of the plateau that includes the Dolly Sods Wilderness. They sit in a high-elevation heathland punctuated with wind-carved sandstone outcrops and is home to more than a dozen rare plant and animal species. Situated on the crest of the Allegheny Front, Bear Rocks afford vistas over the South Branch Potomac River. Visibility can extend eastward to the Shenandoah National Park in Virginia.
Pruning shears, also called hand pruners, or secateurs, are a type of scissors for use on plants. They are strong enough to prune hard branches of trees and shrubs, sometimes up to two centimetres thick. They are used in gardening, arboriculture, farming, flower arranging, and nature conservation, where fine-scale habitat management is required.
Krummholz or krumholtz — also called knieholz — is a type of stunted, deformed vegetation encountered in subarctic and subalpine tree line landscapes, shaped by continual exposure to fierce, freezing winds. Under these conditions, trees can only survive where they are sheltered by rock formations or snow cover. As the lower portion of these trees continues to grow, the coverage becomes extremely dense near the ground. In Newfoundland and Labrador, the formation is known as tuckamore. Krummholz trees are also found on beaches such as the Oregon coast, where trees can become much taller than their subalpine cousins.
The plant pathogenic fungus Leucostoma kunzei is the causal agent of Leucostoma canker a disease of spruce trees found in the Northern Hemisphere, predominantly on Norway spruce and Colorado blue spruce. This disease is one of the most common and detrimental stem diseases of Picea species in the northeastern United States, yet it also affects other coniferous species. Rarely does it kill its host tree; however, the disease does disfigure by killing host branches and causing resin exudation from perennial lesions on branches or trunks.
Salt pruning is the process by which saline mists generated by seawater are driven ashore by winds and thus over time alter the shape of trees or shrubs. The process degrades foliage and branches on the windward side of the plant that faces the body of saline water, more than it does the foliage on the landward side. The resultant growth form is asymmetrical, appearing "swept back" away from the ocean.
The use of vine training systems in viticulture is aimed primarily to assist in canopy management with finding the balance in enough foliage to facilitate photosynthesis without excessive shading that could impede grape ripening or promote grape diseases. Additional benefits of utilizing particular training systems could be to control potential yields and to facilitate mechanization of certain vineyard tasks such as pruning, irrigation, applying pesticide or fertilizing sprays as well as harvesting the grapes.
A root pruning container is an aid to the cultivation of young plants and trees in nurseries. Many pot designs train the roots. One example is a truncated plastic cone in which a seedling is planted. There is a drainage hole at the bottom and the main tap root tends to grow towards this.
Spruce broom rust or yellow witches' broom rust is a fungal plant disease caused by the basidiomycete fungus known as Chrysomyxa arctosphyli. It occurs exclusively in North America, with the most concentrated outbreaks occurring in northern Arizona and southern Colorado on blue and Engelmann spruce, as well as in Alaska on black and white spruce. This disease alternates its life cycle between two hosts, with the spruce serving as the primary host and bearberry serving as the secondary or alternate host. The name for the disease comes from the distinctive “witches broom”, commonly yellow in color, which forms on the spruce after young needles have been infected. Management must be carried out through physical or mechanical methods, such as the pruning of brooms or the removal of the secondary host from the area, because no chemical control measures have yet been determined to be economically effective. Generally, spruce broom rust is seen as a mostly cosmetic issue, and it is very rarely the direct cause of tree death; however, research has shown a reduction in overall productivity and health of infected trees, making it an important issue for logging and timber companies.
