Potential use of bialaphos, a microbially produced phytotoxin, to control red raspberry in forest plantations and its effect on black spruce

1991 ◽  
Vol 21 (4) ◽  
pp. 489-497 ◽  
Author(s):  
Robert Jobidon
Keyword(s):  
Active Ingredient ◽  
Photosynthetically Active Radiation ◽  
Black Spruce ◽  
Growth Increment ◽  
Height Growth ◽  
First Year ◽  
Quadratic Relation ◽  
Foliar Injury ◽  
Red Raspberry ◽  
Active Radiation

Bialaphos foliar sprays were tested in eastern Quebec for control of red raspberry (Rubusidaeus L.), and the tolerance of planted black spruce (Piceamariana (Mill.) B.S.P.) seedlings was determined. Approximately 3 weeks after bialaphos was applied in July, August, or September, virtually all raspberry plants were killed. Efficiency of the June application, however, was much reduced. Spruce current-year foliage was more affected than older foliage. Foliar injury was more pronounced for bialaphos applications in June and July than for applications in August. First-year spruce survival was not affected by the treatments. Second-year evaluations revealed a significant quadratic relation of (i) month of application × bialaphos rate on raspberry density and (ii) bialaphos rate on raspberry height growth. Reduction in raspberry density and height growth was greater with the 2.0 and 2.5 kg active ingredient per hectare rates applied in August. As part of the evaluation of treatment efficiency, photosynthetically active radiation reaching spruce seedlings was measured using a portable integrating radiometer. Raspberry density and height growth were both negatively correlated with photosynthetically active radiation reaching spruce seedlings. A significant quadratic relation was found between bialaphos rate and 2nd-year spruce survival, which reached 95%, regardless of month and rate of application. A significant quadratic relation was found between spruce diameter growth increment and bialaphos rate. Except for calcium, 2nd-year spruce foliar mineral content was not affected by the treatments. Bialaphos treatments in August, with rates ranging from 1.0 to 2.0 kg active ingredient per hectare, had only slight or no adverse effects on spruce survival, foliar injury, and growth increment. Selective control of red raspberry in young black spruce plantations is a function of bialaphos rate and month of application.

Light threshold for optimal black spruce (Piceamariana) seedling growth and development under brush competition

1994 ◽  
Vol 24 (8) ◽  
pp. 1629-1635 ◽  
Author(s):  
Robert Jobidon
Keyword(s):  
Tree Growth ◽  
Black Spruce ◽  
Growth Increment ◽  
Height Growth ◽  
Light Interception ◽  
Stem Diameter ◽  
Tree Seedlings ◽  
Relative Growth ◽  
Competing Vegetation ◽  
Total Height

Light threshold is suggested as a method for quantifying brush competition in black spruce (Piceamariana (Mill.) B.S.P) plantations and predicting losses in tree growth as measured by the relative growth rate (RGR). The severity of the competing vegetation (expressed in terms of density and height) around 300 planted tree seedlings, and the growth status of the seedlings (expressed in terms of total height and current height growth increment), were analyzed simultaneously with multivariate analysis of variance (MANOVA), with one level of light quantity (photosynthetically active radiation) reaching the upper one-half of the tree seedlings as the predictor variable. This study showed that it is possible to establish a competitive status based on light interception, thus allowing a grouping of seedlings with similar growth characteristics and severity of competition. Canonical analysis showed that 60% of full sunlight reaching the upper one half of spruce seedlings can be defined as a threshold to significantly discriminate between stressed and unstressed tree seedlings, based on the above-mentioned variables and also based on spruce basal stem diameter. For spruce total height, current height increment, and basal stem diameter, significant differences were found between plots above and below this threshold, averaging 18.5, 44.7, and 23.2%, respectively. Measuring the intensity of light reaching the upper one half of the spruce seedlings also significantly explains spruce relative growth rates, expressed in terms of height growth increment and basal stem diameter growth increment over the following two growing seasons. The light threshold used in the MANOVA and the ANOVA showed significant differences between plots above and below the threshold, averaging 70 and 58% for spruce height and basal stem diameter RGRs, respectively. Instead of measuring competing vegetation variables and relative height of a crop species to infer light interception, this study demonstrated that a direct measure of light attenuation at the tree seedling level can be used to assess the competitive status and predict losses in tree growth for the period of time required by the seedlings to emerge from the vegetation cover. Moreover, this study demonstrated that canonical relations, rather than linear relations, explain the pattern of competition for light between young spruce seedlings and brushlike vegetation. The light threshold suggested in this study has potential for assessing interspecific competition problems in young black spruce plantations and is proposed as a tool to support a containment strategy of vegetation management.

Benomyl Root Dips Adversely Affect First-Year Performance of Stored Loblolly Pine Seedlings

1991 ◽  
Vol 15 (3) ◽  
pp. 133-137 ◽  
Author(s):  
Nancy J. Stumpff ◽  
David B. South
Keyword(s):  
Loblolly Pine ◽  
Active Ingredient ◽  
Height Growth ◽  
Prolonged Storage ◽  
First Year ◽  
Pine Seedlings ◽  
Beneficial Response ◽  
Clay Slurry ◽  
Survival Of Seedlings

Abstract Dipping loblolly pine roots into a clay slurry containing benomyl (1.25% active ingredient) at the time of packing did not improve survival of seedlings stored (near 3°C) for 1 to 4 weeks. In some situations, benomyl decreased out-planting survival. Regardless of lifting date or storage length, benomyl slightly decreased first-year height growth (by 12 to 17%). Although previous research has demonstrated that a benomyl treatment can improve the ability of March-lifted seedlings to withstand prolonged storage, a beneficial response is not yet predictable for loblolly pine seedlings lifted between October and February. South. J. Appl. For. 15(3):133-137.

Mortality of balsam fir and black spruce advance growth 3 years after clear-cutting

1995 ◽  
Vol 25 (9) ◽  
pp. 1528-1537 ◽  
Author(s):  
Jean-Claude Ruel ◽  
René Doucet ◽  
Jocelyn Boily
Keyword(s):  
Logistic Regression ◽  
Black Spruce ◽  
Height Growth ◽  
Seedling Quality ◽  
Balsam Fir ◽  
First Year ◽  
Logging Damage ◽  
Clear Cutting ◽  
Lean Angle ◽  
Logistic Regressions

The effects of balsam fir (Abiesbalsamea (L.) Mill.) and black spruce (Piceamariana (Mill.) B.S.P.) seedling attributes on survival were measured on four cutovers regenerated to black spruce and three regenerated to balsam fir. In each of these, about 240 stems were permanently identified shortly after logging and their main characteristics were noted. Survival was assessed after 1 and 3 years. First-year mortality reached 24% for balsam fir and and 21% for black spruce. It varied with height and seedling quality. Mortality during the second and third year after harvesting was less important and was more evenly distributed between the different height classes. When all height classes were combined, the logistic regression calculated for total balsam fir mortality was able to correctly classify the observations in 74% of the cases by using three variables: prerelease height growth, lean angle, and a wound index. For black spruce, seven variables were needed to correctly classify 78% of the observations. These were: height, prerelease height growth, live crown ratio, lean angle, distance to the straightening point, and two wound indices. Separate logistic regressions were calculated for stems smaller or taller than 30 cm. These regressions performed considerably better for the taller height class for both species. For balsam fir, lean angle and one or another wound index still remained in relation with survival. For black spruce, prerelease height growth and lean angle remained in relation with survival. Distance to the straightening point was only retained for stems below 30 cm while live crown ratio and the two wound indices were retained for stems over 30 cm. These results suggest that an evaluation of seedling quality using measures of previous suppression and logging damage should be introduced in regeneration surveys to better predict the evolution of a cutover after harvesting.

Differential tolerance of coniferous species to the microbially produced herbicide bialaphos. I. Morphological and growth effects

1994 ◽  
Vol 24 (11) ◽  
pp. 2191-2198 ◽  
Author(s):  
Mlkaĭlou Sy ◽  
Robert Jobidon ◽  
Hank Margolis
Keyword(s):  
Active Ingredient ◽  
Black Spruce ◽  
Survival Rates ◽  
Significant Negative Correlation ◽  
Foliar Injury ◽  
Eastern Canada ◽  
Relative Growth ◽  
Growing Seasons ◽  
Application Rates ◽  
Visible Foliar Injury

Four species of boreal conifer seedlings used for reforestation in eastern Canada were tested for their tolerance to the microbially produced herbicide bialaphos under controlled conditions. The tolerance levels of white spruce (Piceaglauca (Moench) Voss), black spruce (Piceamariana (Mill.) B.S.R), Norway spruce (Piceaabies (L.) Karst.), and red pine (Pinusresinosa Ait.) were studied over two consecutive growing seasons using different morphological and growth criteria. Application rates were the equivalent of 0, 1.0, 1.5, 2.0, 2.5, and 3.0 kg active ingredient (bialaphos) per hectare in a 1400-L solution and were applied in July, August, or September. Survival rates were a linear function of the dose of bialaphos, but were greater than 95% for all treatments. Results indicated that there was no significant correlation between visible foliar injury and the amount of epicuticular wax on needles. There was also no significant correlation between visible foliar injury and initial seedling height. However, a significant negative correlation was observed between the degree of foliar injury and the relative growth rate following treatment. No additional foliar injury occurred during the second growing season. Doses of bialaphos that did not exceed the equivalent of 2.0 kg active ingredient per hectare had no effect on subsequent growth. Tolerance was greatest when the herbicide was applied in August and least when applied in July. These results, combined with the lower tolerance previously demonstrated for several species that compete with planted conifers in eastern Canada, suggest that bialaphos has a strong potential as an alternative to chemically synthesized herbicides for vegetation management in conifer plantations.

Impact du drainage forestier après coupe sur la croissance de l'épinette noire en forêt boréale

2002 ◽  
Vol 32 (9) ◽  
pp. 1585-1596 ◽  
Author(s):  
Sylvain Jutras ◽  
Jean Bégin ◽  
André P Plamondon
Keyword(s):  
Picea Mariana ◽  
Black Spruce ◽  
Growth Increment ◽  
Height Growth ◽  
Forest Stand ◽  
Stem Analysis ◽  
Ecological Conditions ◽  
Drainage Networks ◽  
Periodic Growth ◽  
Ecosystem Classification

The objective of this study was to retrospectively evaluate, with the help of stem analysis, the growth increases of natural and planted black spruce (Picea mariana (Mill.) BSP) seedlings in 39 drainage networks located in Quebec public boreal forest and drained operationally after cutting. The ecological conditions of the sites have been described using the forest ecosystem classification for the Clay Belt of eastern Ontario. A significant effect of the drainage on 9-year periodic growth in diameter and height of natural black spruce seedlings, varying with distance from the ditch and ecological conditions, was observed. Stocking of natural black spruce seedlings was sufficient to insure the reconstruction of a forest stand both on the treated sites and on the control sites. The 5-year height growth increment of planted black spruce seedlings was weaker than that of the natural seedlings, which were located on the same sites, and it varied with distance from the ditches.

scholarly journals Ground level photosynthetically active radiation dynamics in stands of Acacia mearnsii De Wild

2015 ◽  
Vol 87 (3) ◽  
pp. 1833-1845 ◽  
Author(s):  
SYLVIO PÉLLICO NETTO ◽  
CARLOS R. SANQUETTA ◽  
BRAULIO O. CARON ◽  
ALEXANDRE BEHLING ◽  
AUGUSTO A. SIMON ◽  
...  
Keyword(s):  
Photosynthetically Active Radiation ◽  
Inflection Point ◽  
Soil Surface ◽  
Ground Level ◽  
Height Growth ◽  
Rio Grande Do Sul ◽  
Acacia Mearnsii ◽  
Active Radiation ◽  
Breast Height ◽  
Closed Canopy

ABSTRACTThe objective is to study the dynamics of photosynthetic radiation reaching the soil surface in stands of Acacia mearnsii De Wild and its influence on height growth in stands. This fact gives rise to the formulation of the following hypothesis for this study: "The reduction of the incidence of light inside the stand of black wattle will cause the inflection point in its height growth when this reaches 4 to 5 m in height, i.e. when the stand is between 2 and 3 years of age". The study was conducted in stands in the state of Rio Grande do Sul, Brazil, where diameters at breast height, total height and photosynthetically active radiation available at ground level were measured. The frequency tended to be more intense when the age of the stands increases. It was evident that a reduction of light incidence inside the forest occurred, caused by canopy closure. Consequently, closed canopy propitiated the competition of plants. This has affected the conditions for growth in diameter and height of this species, reason why it becomes possible to conceive the occurrence of an inflection point in the growth of these two variables, confirming the formulated hypothesis.

Sign in / Sign up

Export Citation Format

Share Document