Frost heaving of tree seedlings : a literature review of causes and possible control /

Abstract

Heidmann, L. J.1976. Frost heaving of tree seedlings: A literature review of causes and possible control.USDA For. Serv. Gen. Tech. Rep. 10 p. Rocky Mt. For. and Range Exp. Stn., Fort Collins, Colo. Frost heaving of tree seedlings is more serious among seedlings less than 1 year old than among transplanted stock. It appears to be a surface soil phenomenon, and occurs because of a segregation of soil water which freezes into layers or lenses of ice. Lens formation causes an uplift of the surface soil and the tree seedling. Upon thawing, the tree remains in an extruded position on the soil surface while the soil recedes to approximately its original level. Segregation of the soil water occurs within the total matrix because of supercooling of the water in smaller soil pores and the water adsorbed on soil particles. The difference in freezing points provides the energy necessary to draw water to the ice lens and to lift the surface. Segregation of soil water is related to soil permeability and negative pressure on the water. A silty soil is more likely to heave because the right combination of permeability and tension can be developed. Heaving in a clay soil is determined to a great extent by the type of clay and the nature of the ions adsorbed by the clay particles. Heaving can be controlled by lowering the freezing point of the soil water, by restricting the water flow to the freezing front, or by cementing the soil particles together. Chemicals such as calcium chloride have been successful in reducing frost heaving by lowering the freezing point of the soil water.Dispersing agents, mainly sodium compounds, reduce heaving by plugging the soil pores, thus limiting water movement to the freezing front and subsequent growth of ice lenses. Cementing agents make the soil less frost susceptible by reducing the proportion of finer soil particles (clay and silt).

A New Method for Delineating Tree Patches and Assessing Spatial Reference Conditions of Ponderosa Pine Forests in Northern Arizona

“…S4A) where no parks are noted but ponderosa pine is known to persist in lower densities (Abella 2008; Dyer et al 2008) as compared to other studies on basalt‐derived soils (Savage et al 1996). Furthermore, we speculate that regardless of study site, spatial aggregation at all scales (≤ 100 m) is to be expected in areas with increased seedling mortality, likely resulting from frost‐heaving (Heidmann 1976), periods of extreme drought (Larson & Schubert 1970), and/or increased competition from herbaceous plants for important resources such as soil moisture (Larson & Schubert 1969).…”

Presettlement Regeneration Patterns in a Southwestern Ponderosa Pine Stand

“…The greatest threat was probably from fire if fuel loads within the young patch of seedlings became too great, but certainly other factors, such as frost heaving (Heidmann 1976), also played a role. First, adequate seed production was necessary; this eliminates years where virtually no seed was produced, but no data are available to suggest what the minimum number of seeds might have been in presettlement times.…”

Phytogeomorphic Influence of Stone Covers and Boulders on Plant Distribution and Slope Processes in High‐Mountain Areas

“…Seedling damage occurs when the plant stem or root collar is gripped by a frozen ground crust; when pushed upwards by growth of underlying ice, seedling roots break. Roots branch downward, therefore cannot settle back in place, and become gradually exposed after several heaving events; eventually plants are ejected from the ground (Heidmann 1976; Schramm 1958). Seedlings partially heaved die because of root desiccation or disease (Billings and Mooney 1968).…”