Red Pine Trees Research Articles

Surface Soil Acidification under Red Pine and Norway Spruce

AbstractNear‐tree patterns of forest‐soil pH under red pine (Pinus resinosa Ait.) and Norway spruce [Picea abies (L.) Karst.] were examined in order to evaluate the role of trees in acidification processes of surface soils. Variability in soil pH was analyzed by comparing samples obtained at different distances and directions from the base of a tree, at different times within a year, under live and dead trees, trees of different sizes, and trees of the same species growing on different soil types. Accumulation of soil organic matter, pH of freshly fallen litter, and the concentration of oxalate in water extracts of Oe horizons were measured as a function of distance from the base of selected trees. A significant decrease in soil pH from the edge of the canopy to the base of the tree was found in the upper mineral soil and organic horizons beneath live trees of both species. In general, the direction of sampling, the percent organic matter within a soil sample, and the time of year for sampling did not significantly affect soil pH. Mass of organic matter above the mineral soil did not exhibit a distinct pattern with distance from a tree. Twelve years after thinning red pine trees, a significant depression in pH existed in Oi and Oe horizons near the base of a dead tree or stump. Near‐tree depression in pH of the Oi horizon, where tree roots are not present, and of the Oi and Oe horizons around previously thinned trees where no stemflow occurs, suggests that soil fungi endemic or more active in the near‐tree environment of red pine and Norway spruce could make a significant contribution to acidification of soil surface horizons.

Fire and Climate Change During the Last 750 Yr in Northwestern Minnesota

Charcoal stratigraphic analysis and fire scars on red pine (Pinus resinosa) trees were used to determine spatial and temporal occurrence of fire in 1 km2 of old—growth mixed conifer/hardwood forests in northwestern Minnesota. Charcoal was analyzed year by year on petrographic thin sections from annually laminated sediments of three small (≤5 ha) lakes having adjacent catchments. Dated fire scars (n = 150) from recent treefalls provided an independent record of the spatial patterns of past burns. Sedimentology of the varved sediments, water—balance models that use 150 yr of instrumental temperature and precipitation data, and published data were used to identify climate changes in separate studies, and they were used in this study to examine the possible connection between changing fire regimes and climate change. Fire—history data were used to show the changing probability of fire with time since the last fire and the effects of spatial variance (slope and aspect) on the distribution of fires through time. Over the last 750 yr, fire was most frequent (8.6 ± 2.9—yr intervals) during the warm/dry 15th and 16th centuries. Intervals were longer (13.2 ± 8.0 yr) during cooler/moister times from AD 1240 to 1440 and since 1600 (the Little Ice Age). The fire regime during the Little Ice Age consisted of periods during the mid—18th and mid—19th centuries characterized by longer fire intervals of 24.5 ± 10.4 and 43.6 ± 15.9 yr, respectively, and short—term warm/dry periods from 1770 to 1820 and 1870 to 1920 when intervals were 17.9 ± 10.6 and 12.7 ± 10.1, respectively. The probability of fire increased through time, probably in step with fuel accumulation. South— and west—facing slopes burned more frequently than did north and east aspects. Fire suppression began in 1910. During warm periods, probability of fire was sufficiently high that a continuous litter layer was all that was necessary for fire to spread and scar trees. During cool and moist times fire was most likely to occur in years with higher moisture deficits. The combined methods for fire—history analysis provided a more detailed spatial and temporal documentation of fire regimes than has previously been possible from analysis of fire scars or of charcoal counts derived from fossil pollen preparations. Results support predictions of particle—motion physics that thin sections record a local fire history. Because climate varies continuously, the responsiveness of disturbance regime to short— and long—term climatic change suggests caution in the interpretation of fire frequencies that derive from space/time analogies or extrapolation from short—term data.

Ecological Disturbance as a Renewal Process: Theory and Application to Fire History

Failure-time analysis and renewal theory were used to evaluate two assumptions implicit in most studies involving calculations of disturbance frequency. These calculations assume that the disturbance process is stationary (intervals between disturbances are drawn from the same distribution) and that the probability of disturbance does not change with time since the last disturbance. I present quantitative methods and apply them to long-term fire-occurrence data (fire scars on red pine trees and stratigraphic charcoal data) and climate data from northwestern Minnesota. Results show that past decade- and century-scale fluctuations in climate correspond to changes in the disturbance regime. Probability of fire occurrence increases with time since the last fire, albeit at different rates during the various climatic settings that have prevailed over the last 750 yr. These results suggest two reasons to question disturbance regimes calculated from spatial dispersion of events. First, expected fire intervals derived as the inverse of the spatial proportion of area disturbed requires a stationary process. The space-time analogy assumed by this method is importantly wrong when the expected interval between disturbances changes over time. Second, because fire hazard is an increasing function of time since the last fire, the number of disturbances predicted to occur over short time intervals will be overestimated by the usual constant-hazard assumption. Probability densities of events having age-specific probabilities that increase over time (e.g. fire, windthrow) exhibit modes at time t > 0 compared with exponential decrease with time.

Stratigraphic charcoal analysis on petrographic thin sections: Application to fire history in northwestern Minnesota

Results of stratigraphic charcoal analysis from thin sections of varved lake sediments have been compared with fire scars on red pine trees in northwestern Minnesota to determine if charcoal data accurately reflect fire regimes. Pollen and opaque-spherule analyses were completed from a short core to confirm that laminations were annual over the last 350 yr. A good correspondence was found between fossil-charcoal and fire-scar data. Individual fires could be identified as specific peaks in the charcoal curves, and times of reduced fire frequency were reflected in the charcoal data. Charcoal was absent during the fire-suppression era from 1920 A.D. to the present. Distinct charcoal maxima from 1864 to 1920 occurred at times of fire within the lake catchment. Fire was less frequent during the 19th century, and charcoal was substantially less abundant. Fire was frequent from 1760 to 1815, and charcoal was abundant continuously. Fire scars and fossil charcoal indicate that fires did not occur during 1730–1750 and 1670–1700. Several fires occurred from 1640 to 1670 and 1700 to 1730. Charcoal counted from pollen preparations in the area generally do not show this changing fire regime. Simulated “sampling” of the thin-section data in a fashion comparable to pollen-slide methods suggests that sampling alone is not sufficient to account for differences between the two methods. Integrating annual charcoal values in this fashion still produced much higher resolution than the pollen-slide method, and the postfire suppression decline of charcoal characteristic of my method (but not of pollen slides) is still evident. Consideration of the differences in size of fragments counted by the two methods is necessary to explain charcoal representation in lake sediments.

Pathogenicity of Bursaphelenchusxylophilus on three species of pine

Three species of 11-year-old pine trees were inoculated with Bursaphelenchusxylophilus in the field. Four branches in single whorls on red, Scots, and jack pine trees were wounded and inoculated with 10 000 nematodes each or with water extracts from Botrytiscinerea cultures. Prior to field inoculations, the pathogenicity of the nematode isolate was confirmed on seedlings in the greenhouse. Fourteen weeks after inoculation, 27 of 80 and 13 of 52 branches were dead or dying on Scots and jack pine trees, respectively. No symptoms were observed on red pine trees inoculated with B. xylophilus or on any controls. Branch death was attributed to the formation of girdling cankers resulting from inoculation. An average of 9.14, 10.39, and 0.02 nematodes were extracted per gram of wood from branch samples collected from Scots, jack, and red pine trees at 14 weeks, respectively, and at 58 weeks an average of 13.82, 1.01, and 0.05 nematodes per gram of wood sampled were recovered. Proportions of branch samples with nematodes declined from 14 to 58 weeks after inoculation. Although limited mortality of branches occurred, the pine wood nematode was not found to cause tree death following inoculation.

Participation of .BETA.-myrcene in the susceptibility and/or resistance of pine trees to the pine wood nematode, Bursaphelenchus xylophilus.

The relationship of the β-myrcene content with the susceptibility and/or resistance of Pinus species against the pine wood nematode was investigated. For this purpose, the β-myrcene content of the wood of one-year-old shoots was determined. The resistant trees were found to contain a very small amount of β-myrcene. On the other hand, the β-myrcene content of susceptible trees was comparatively high. This relationship was observed in both inter- and intraspecies and also between young and older trees of the same species, i.e., Pinus densiflora or P. thunbergii. The β-myrcene content can feasibly be used as an indicator for screening resistant Japanese red and black pine trees.

Effects of forest vegetation on spatial variability of surface mineral soil pH, soluble aluminum and carbon

The purpose of this study was to examine spatial variability in forest soils at several levels including variability due to soil structure, to the presence of individual trees and to populations of different species of trees. Both classic statistical and geostatistical methods were used. Soil chemical properties measured include pH and A1 and C in solution which was in equilibrium with the surface mineral soil. Results indicated that soil cores 1.8 cm in diameter were as effective as larger cores in incorporating variability in surface mineral soil pH. There was no spatial correlation in soil pH in samples separated by a distance of 20 to 360 cm. The presence of individual Norway spruce and red pine trees affected soil in their vicinity. Soil pH was depressed and soluble A1 elevated in soil near the base of the tree compared to soil 120 cm from the tree, independent of direction. In addition, in soil sampled at least 100 cm from the base of trees, pH was lower in Norway spruce compared to sugar maple plantations and soluble C was greater in red pine compared to Norway spruce plantations. It is concluded that in less than 50 yr the presence of individual trees and populations of different tree species can affect chemical properties of surface mineral soils. These effects should be considered in the design and interpretation of experiments.

Ecological Studies on Formica yessensis Forel, with Special Reference to Its Effectiveness as a Biological Control Agent of the Pine Caterpillar Moth in Korea : V. Usefulness of Formica yessensis Forel

Two experiments of artificial colonization of Formica yessensis were conducted in several red pine stands of Gyeongsang-Na m-Do, Korea in 1972 and 1977. The ant easily established in forests growing 10 to 20-year-old red pine trees at a relatively high density but admitting sunlight to the forest floor, harbouring much bare grounds and long graminaceous grasses. The ant favours soils with much organic material and rather high moisture content but not wet excessively.

Effects of environmental factors on estimated daily radial growth ofPinus resinosa andBetula papyrifera

Relations between estimated daily radial growth of red pine (Pinus resinosa) and white birch (Betula papyrifera) trees and various environmental factors were studied in northern Wisconsin. Daily variations in stem radius, which reflected an irreversible cambial growth component as well as superimposed shrinkage and swelling of stems, were recorded with dendrographs and daily radial growth was estimated with trend lines connecting midpoints between daily maximum and minimum stem radii. Orthogonalized regression analysis was used to isolate individual effects despite intercorrelations between the variables. Regression models were developed on 9 independent variables: rainfall (log P, n), minimum temperature (Tmin, n; Tmin 2, n), average daily relative humidity (Ra, n), maximum saturation deficit with a one-day lag (Vmax, n−1), minimum temperature with a two-day lag (Tmin, n−2), percent soil moisture (log M150), time trend (Day2) and autocorrelation (y, n−1). These factors explained 81% of the variation in estimated daily radial growth of birch. They also explained 78% of the variation in growth of pine at the wettest site (lower slope) and 64% at the driest site (upper slope). As soil and plant water stress intensified up the slope, radial growth of pine was inhibited and the direct relation between growth and environmental factors was progressively weakened while the autocorrelation factor became dominant. Rainfall (log P, n) was the most important factor influencing radial growth, reflecting the paramount importance of cell turgor in the cambial zone.

The development of a more virulent strain of Scleroderris lagerbergii in New York State

Scleroderris canker has recently killed several thousand hectares of large red and Scotch pine trees in northern New York State. The disease pattern indicates that a new more virulent strain of S. lagerbergii is now present in North America.

Effect of insect growth regulators and fertilizers applied as foliar sprays during the egg stage of the sawfly Neodiprionsertifer

Two insect growth regulators, a mixture containing about 25% Cecropia juvenile hormone with its geometrical isomers (AY-22342-3: Ayerst Research Laboratories, Saint-Laurent, Quebec) and a preparation containing 75% of the aromatic terpenoid ether, 4-ethylphenyl-6,7-epoxygeranyl ether (R-20458-B: Stauffer Chemical Co., Mountain View, California), were tested under field conditions for ovicidal activity against eggs of Neodiprionsertifer (Geoff.). Single egg clusters on Scots pine (Pinussylvestris L.) and whole red pine (P. resinosa Ait.) trees were sprayed to the drip point with formulations containing 0.1, 1, or 10 g/litre of insect growth regulator. AY-22342-3 reduced egg hatch at 10 g/litre on both tree species but was more effective in the red pine trial. R-20458-B did not reduce egg hatch significantly. Results with AY-22342-3 in the laboratory were about twice as effective as field trials. The application of fertilizers (urea, KNO3, or NH4NO3) accompanying a spray of AY-22342-3 on whole red pine trees does not enhance larval mortality. For trees receiving relatively intensive care, notably ornamentals and Christmas trees, the ovicidal activity of insect growth regulators might be useful as a means of preventing sawfly defoliation.

Respiration rates of red pine along a gradient of gamma radiation following eight years of exposure

Eleven-year-old red pine trees that had lived for eight yr along a gradient of gamma radiation changed little in respiration rates between exposure rates of 1·0–4·0 rads/day. Between 4·0–6·0 rads/day, respiration rates increased by an average of 54 per cent, and between 6·4 and 6·8 rads/day, respiration rates decreased by an average of 26 per cent. The increase in respiration rates may be due to oxygen consuming repair mechanisms. The decrease in respiration rates may result from reduced rates of cell division or reduced activity of growth hormones. The decrease probably did not result from dead tissue comprising part of the sample.

Foliar nutrition and wood growth in red pine: effects of darkening and defoliation on the distribution of 14C-photosynthate in young trees

Young red pine trees were supplied with 14CO2 through a branch in the third whorl. Darkening or removal of all other needles caused a major diversion of 14C to the expanding terminal shoot. Defoliation had a much greater effect than darkening. The diversion can be only partially explained on the basis of removal of competing sources of carbohydrate. Use as well as distribution of labeled photosynthate was affected by the treatments.

Water Potential in Red Pine: Soil Moisture, Evapotranspiration, Crown Position

Diurnal patterns in leaf water potential were examined on eight red pine trees throughout one summer in northern Minnesota. The daily high in leaf water potential was plotted against total soil moisture to produce a soil—moisture release curve characterizing the plant—soil—atmosphere system. Diurnal patterns in leaf water potential at various soil moistures were compared. Also compared were patterns in leaf water potential under high and low evaporational demand and constant soil moisture. Results were generally consistent with previously constructed models. Very little variation in leaf water potential was observed among whorls or needle ages. Laboratory studies of the effects of leaf water potential when synthesized with data from the forest on occurrence of leaf water potentials suggest that growth was limited by water deficit every day of the 1969 summer.

Response ofPinus resinosa ait. Plantations to potassium fertilization on a potassium-deficient site

Using deviations of the cumulative height growth due to fertilization treatments from the linear finite difference curve of untreated red pine trees in plantations, it was noted that: 1) large-sized trees responded in height growth to fertilization in the year following treatment while the medium and small trees took two years to respond; 2) medium-size trees responded to fertilization similar to large trees, but to a lesser magnitude; and 3) small trees are further suppressed by fertilization due to growth responses in the large medium trees.

GROWTH REGULATOR CHANGES IN RELATION TO GROWTH AND DEVELOPMENT OF PINUS RESINOSA AIT.

The occurrence of growth regulators and nucleic acids in buds of red pine trees has been investigated in relation to seasonal change, position of the bud in the crown, and age of the tree. The regulators were extracted, separated by chromatography, and assayed by an Avena straight-growth test. Three growth promoters and an inhibitor were found in the buds on all occasions. All of them affected the growth of hypocotyls of red pine seedlings as well as Avena inter-nodes, and none gave an indole reaction. The regulators varied in concentration in relation to season, age, and bud position. The individual growth promoters varied independently, one of them, designated as P1, being more variable than the others. Changes in the inhibitor were frequently, but not invariably, reciprocal to those of P1. There is evidence that individual growth promoters may be concerned with separate aspects of growth. The balance between P1 and the inhibitor was related to extension growth, with the notable exception that a balance favorable to growth reappeared in September, when no growth occurs. RNA concentration declines during the summer and a deficiency of this nucleic acid could be implicated in the cessation of growth.Treatment with ammonium nitrate fertilizer caused a shift from male to female cone production and a localized increase in the number of shoots that developed in the following year. These effects were accompanied by changes in concentration of growth promoters in the buds.

Distribution of the European Pine Shoot Moth, Its Parasites, and Associated Insects in Red Pine Trees and Stands

Twenty species of parasites and associated insects were reared from shoots of red pine, Pinus resinosa Ait., infested with the European pine shoot moth, Rhyacionia buoliana (Schiffermuller), at Oakland, Md. In trees 7 ft tall, Hyssopus thymus Girault was more abundant than Exeristes comstockii Cresson, but the reverse was true in trees half that height. Total parasitism and parasitism by H. thymus and Eurytoma pini Bugbee were greater in the lowest ⅓ than in the topmost ⅓ of the tree; E. comstockii and associated insects of uncertain status—lepidopterans, coleopterans, and the dipteran Oscinella conicola (Green)—were most abundant in the topmost ⅓. Of Itoplectis conquisitor (Say) only males were reared. Usually only 1 shoot moth larva was found per shoot, but occasionally there were as many as 5; more than 1 larva per shoot occurred more often in the topmost than in the lowest ⅓ of the trees. Trees 3½ ft tall had a higher infestation rate than those 7 ft tall. Lammas shoots were infested at the same rate as normal shoots. In 3½-ft trees, 23% of the shoots were in the lowest ⅓ and 24% in the topmost ⅓ of the tree; in 7-ft trees, 50% and 10%, respectively.

OBSERVATIONS ON FOLIAGE NUTRIENT CONTENT OF SEVERAL CONIFEROUS TREE SPECIES IN BRITISH COLUMBIA

Concentration of nitrogen, phosphorus, potassium, calcium, magnesium and sulphur in needles of alpine fir, amabilis fir, western red cedar, Douglas fir, western hemlock, lodgepole pine, Engelmann spruce and Sitka spruce trees growing in a number of areas of British Columbia was determined.Concentration of N, P, K, Ca, Mg and S in current needles of three groups of alpine fir seedlings was 1.05-1.85, 0.18-0.26, 0.70-1.08, 0.29-.044, 0.07-0.11, and 0.12-0.16 per cent, respectively. The nutrient content in the same order was 0.99, 0.16, 1.20, 0.30, 0.08, and 0.12 per cent in a single group of amabilis fir samples.In the lone set of western red cedar samples the concentrations of N, P, K, Ca, Mg and S were in the order of 0.73, 0.13, 0.52, 1.16, 0.10 and 0.07 per cent.The percentage of the six nutrients in current Douglas fir needles from seven locations was 0.88-1.37, 0.12-0.22, 0.38-0.70, 0.16-0.44, 0.07-0.18, and 0.14-0.25 for N, P, K, Ca, Mg and S, respectively.The nutrient content of current needles of western hemlock from three sites was N = 0.86-1.17, P = 0.11-0.19, K = 0.28-0.57, Ca = 0.18-0.27, Mg = 0.08-0.12 and S = 0.10-0.15 per cent.Nitrogen, P, K, Ca, Mg and S concentration in current needles from three lots of lodgepole pine seedlings was 1.18-1.77, 0.15-0.18, 0.45-0.62, 0.16-0.26, 0.11-0.14 and 0.12-0.21 per cent, respectively. The corresponding values in needles from older trees were in the order 0.97-1.12, 0.09-0.12, 0.35-0.39, 0.15-0.16, 0.08-0.12 and 0.09-0.11.Per cent N, P, K, Ca, Mg and S in current needles of three groups of Engelmann spruce seedlings was in the order 1.26-1.72, 0.21-0.29, 0.71-0.80, 0.44-0.58, 0.13-0.15 and 0.13-0.19. Concentration of these nutrients in older trees was 0.92-1.08, 0.20, 0.70-0.88, 0.28-0.33, 0.11-0.12 and 0.12-0.14 per cent, respectively.

The Role of Reserves in Leaves, Branches, Stems, and Roots on Shoot Growth of Red Pine

By defoliation, girdling, and various combinations of these before the growing season began, the role of foods in old needles, branches, main stems, and roots on shoot growth of 8-yr-old red pine (Pinus resinosa) trees was studied in northern Wisconsin. Defoliation and girdling, alone or in combination, reduced shoot growth but defoliation reduced shoot dry weight more than it reduced shoot elongation. Reductions in shoot growth due to treatment were in the following decreasing order: branch girdling + needle removal > girdling at stem base + needle removal > needle removal > branch girdling > base girdling. The old needles were the major source of food for shoot growth and accounted for four-fifths or more of all shoot growth. The combined reserves in the branches, main stem, and roots accounted for less than 15% of shoot growth. The contribution of reserves from tissues other than old leaves was in the following order: branches > main stem > roots. Defoliation weakened apical dominance relations. In defoliated trees, many secondary axes elongated more than the terminal leader, and secondary axes in lower whorls often grew more than those in upper ones. The data suggest an important role of nutritional factors in correlative growth inhibition.

THE ROLE OF RESERVES IN LEAVES, BRANCHES, STEMS, AND ROOTS ON SHOOT GROWTH OF RED PINE

By defoliation, girdling, and various combinations of these before the growing season began, the role of foods in old needles, branches, main stems, and roots on shoot growth of 8‐yr‐old red pine (Pinus resinosa) trees was studied in northern Wisconsin. Defoliation and girdling, alone or in combination, reduced shoot growth but defoliation reduced shoot dry weight more than it reduced shoot elongation. Reductions in shoot growth due to treatment were in the following decreasing order: branch girdling + needle removal > girdling at stem base + needle removal > needle removal > branch girdling > base girdling. The old needles were the major source of food for shoot growth and accounted for four‐fifths or more of all shoot growth. The combined reserves in the branches, main stem, and roots accounted for less than 15% of shoot growth. The contribution of reserves from tissues other than old leaves was in the following order: branches > main stem > roots. Defoliation weakened apical dominance relations. In defoliated trees, many secondary axes elongated more than the terminal leader, and secondary axes in lower whorls often grew more than those in upper ones. The data suggest an important role of nutritional factors in correlative growth inhibition.