Articles by S. A. Wilde

Certain biocides used in production of tree nursery stock exterminate undesirable organisms but cause an abnormal growth stimulation of plants. The reforestation material has decreased survival potential because of high degree of succulence, top:root and height:diameter ratios, and low specific gravity and root surface area. Some fumigants impede mycorrhizae development and arrest phosphorus uptake. Recovery of growth potential was achieved by aluminium sulphate and/or fermented compost inoculated with mycorrhiza-forming fungi.

The PDF includes a summary in Finnish.

• Iyer, E-mail: ji@mm.unknown
• Chesters, E-mail: gc@mm.unknown
• Wilde, E-mail: sw@mm.unknown

This study estimates the supply of soil water required for the annual and total production of energy material by the biomass of 32-year-old plantation of red pine, Pinus resinosa Ait. in Wisconsin, the United States.

The supply of transpiration water was determined as the sum of summer precipitation, winter stored water, and condensed vapor, minus gravitational discharge and evaporation of intercepted rainfall. On the average, the 1,20 m root zone of coarse sandy soils of central Wisconsin receives 2,750 M.T. of water per hectare. During the 32nd year of plantation growth, the increment biomass, including 43% of merchantable timber, was 10,100 kg/ha, or 162 x 105 kcal/g. At this time of the culminating growth, the production of 1 kg of wood material consumed 272 kg of water. The corresponding transpiration coefficient 0,37% is near the maximum for the ecosystem of hard pines – sandy soils of glacial outwash with field capacity between 7 and 9%. On the weight basis, the annual leaf fall constituted 32% of the biomass and over 80% of merchantable timber.

The entire supply of water of 96,000 M.T./ha produces in 32 years 211,112 kg of total dry matter at a rate of 1 kg of wood per 455 kg of water, with corresponding transpiration coefficient of 0,22%. The evapogravitational losses during the early stages of the stand’s growth decreased the water utilization efficiency of trees about 40%.

The information obtained permitted to outline several hydrological relationships pertinent to forest culture, namely: maximum rate of forest growth as delineated by the supply of available transpiration water; content of available moisture in soils of high tension capacity; contribution to soil water rendered by natural subirrigation and condensation of athmospehric vapor; growth depressing effect of weeds.

The PDF includes a summary in Finnish.

• Wilde, E-mail: sw@mm.unknown

No other manifestation of life is allied more conspicuously to the theory of relativity as the growth of forest stands which is a function of the inherent growth potential of trees, the productive capacity of environment, and time.

The height over age quotient of a forest stand is usually the most reliable indicator of the productive forces of the habitat. Stem analysis have shown that increment of a tree at different ages is closely correlated with the extension of roots into individual geological horizons of different productive capacity. Growth curves of stands of a same tree species growing on different soils can be disparate due to different conditions. The temporal variety of tree growth on different sites is of prime importance in the construction of yield tables. Investigations of natural plant communities of Finland provided one rational approach towards the construction of yield tables. By confining mensuration analyses to define floristic types, the Finnish foresters harmonized their records with Einstein’s formula for space-time matrix of material events.

• Wilde, E-mail: sw@mm.unknown

Result of a survey of soils supporting forest plantations in Wisconsin in the United States indicated a close correlation between the levels of fertility of non-phreatic, coarse-textured soils and the growth of red pine (Pinus resinosa Roezl) stands aged from 15 to 32. This relationship, however was not observed in plantations established on deep-gley soils, underlain at a depth of 3–9 fl by ground water.

The survey encountered 20 red pine plantations on soils underlain by a deep ground water table accessible to tree roots thorough their contact with gley horizon or with extended capillary fringe. The average growth of the stands was 80 cubic feet/acre (5.6 m³/ha) at the age of 22 years. Thus, mensuration analysis suggested that the soils are the choice grounds for forestry enterprise. However, the analysis of soil samples showed that in many instances the soils are extremely low in mineral colloids, organic matter and nutrients. Many of the sites would be regarded as critically deficient in nitrogen, phosphorus and potassium.

The following hypothesis are suggested to explain this discrepancy:

a) The moisture content of coarse-textured non-phreatic soils remain near the wilting point during a large apart of the growing season with subsequent reduction of transpiration and uptake of nutrients. If a capillary fringe provides a supply of water for the root system, trees may derive an adequate supply of salts and exchangeable ions from comparatively infertile substrata.

b) The suitably located ground water provides adequate aeration of the surface soil layers which is not impeded by capillary fringe, increasing activity of mycorrhiza, and a mycotrophic uptake of nutrients from unweathered minerals.

c) The above effects of natural subirrigation should change the concept of soil fertility based on mere chemical analysis. The time during which the roots are engaged in active absorption appears to be of equal importance as the concentration of nutrients in available form.

The PDF includes a summary in Finnish.

• Wilde, E-mail: sw@mm.unknown
• Iyer, E-mail: ji@mm.unknown