Timing and duration of herbaceous vegetation control in northern conifer plantations: 15th-year tree growth and soil nutrient effects

2011 ◽  
Vol 87 (03) ◽  
pp. 398-413 ◽  
Author(s):  
M.K. Hoepting ◽  
R.G. Wagner ◽  
J. McLaughlin ◽  
D.G. Pitt

A 15-year re-measurement of a study designed to identify the optimum timing and duration of herbaceous vegetation control in plantations of four commercial conifer species was completed in northern Ontario. Few differences were revealed in conifer growth when contrasting early and delayed timing of vegetation control. Conversely, each conifer species responded positively to increased duration of vegetation control, with stand volume gains of up to 209% achieved with four to five years of vegetation control following planting. Compared to earlier assessments, the timing of vegetation control appeared less important than duration. Diminishing returns in the fastest-growing species (jack pine [Pinus banksiana Lamb.] and red pine [Pinus resinosa Ait.]) are consistent with intraspecific competition related to the onset of crown closure in these stands. Quantification of a suite of soil nutrient pools along the gradient of increased duration of vegetation control indicated that the more intensive levels of vegetation control did not adversely affect the assessed soil nutrient pools in red pine or jack pine, but a cautionary approach should be considered for white pine (Pinus strobus L.) and black spruce (Picea mariana [Mill.] BSP), where some declines were evident. Vegetation control for two to three years following planting should maximize early conifer growth potential without adverse longer-term effects on soil nutrient pools.

2006 ◽  
Vol 36 (10) ◽  
pp. 2474-2485 ◽  
Author(s):  
Robert G Wagner ◽  
Andrew P Robinson

The influence of the timing and duration of interspecific competition on planted jack pine (Pinus banksiana Lamb.), red pine (Pinus resinosa Ait.), eastern white pine (Pinus strobus L.), and black spruce (Picea mariana (Mill.) BSP) was assessed using 10-year growth responses in a northern Ontario experiment. Stand volume was 117%, 208%, 224%, and 343% higher for jack pine, red pine, white pine, and black spruce, respectively, with 5 years of vegetation control than with no vegetation control. Stand volume increased linearly with number of years of vegetation control, and the slope of the relationship varied among conifer species. Change-point regression analysis was used to derive segmented weed-free and weed-infested curves, and to simultaneously estimate key critical-period parameters. Weed-free and weed-infested curves in the 10th year were similar to those derived in year 5, indicating that the patterns established during the first few years after planting were relatively robust for the first decade. The critical-period was 2 and 3 years after planting for jack pine and red pine, respectively, and occupied most of the 5-year period for white pine and black spruce. Principal components analysis of the vegetation community indicated that repeated herbicide applications caused differential shifts in the relative abundance of shrub, fern, and moss species through the 10th year. Species richness, however, was not substantially different between the untreated control and the most intensive treatments. Difference modeling was used to quantify how annual volume increment during the first decade varied with time, conifer species, cover of woody and herbaceous vegetation, and stage of development.


2019 ◽  
Vol 114 (3) ◽  
pp. 261-276 ◽  
Author(s):  
Christine D. Sprunger ◽  
Steve W. Culman ◽  
Cheryl A. Palm ◽  
Moses Thuita ◽  
Bernard Vanlauwe

2001 ◽  
Vol 133 (3) ◽  
pp. 343-353 ◽  
Author(s):  
Nathan W. Siegert ◽  
Deborah G. McCullough

AbstractHost preference of the pine shoot beetle, Tomicus piniperda (L.), was investigated in two laboratory choice test studies using red pine (Pinus resinosa Ait.) (Pinaceae), jack pine (Pinus banksiana Lamb.), and Scotch pine (Pinus sylvestris L.). Host preference of parent adult beetles was evaluated using freshly cut, similarly sized logs in a wind tunnel. Parent beetles colonized Scotch pine logs significantly more often when given a choice of Scotch pine and either red pine or jack pine logs, but did not show a preference when presented with red pine and jack pine logs. Host preference of progeny adults was tested in a laboratory bioassay using current-year pine shoots. Shoot-feeding progeny adults initiated tunnels in jack pine shoots significantly more often than in Scotch pine and red pine shoots, and preferred Scotch pine over red pine shoots. Shoots with diameters of 0.4–0.5 cm were attacked most frequently, regardless of species. Results suggest that the two North American pines are suitable hosts, but T. piniperda may be most likely to colonize Scotch pine, a European species. Efforts to detect or monitor T. piniperda populations in the Great Lakes and northeastern regions should focus on areas with abundant Scotch pine brood material. Progeny that emerge from brood material, however, may be as likely to shoot-feed in jack pine as in Scotch pine.


1952 ◽  
Vol 84 (2) ◽  
pp. 59-61
Author(s):  
A. S. West

Leconte's sawfly or the red-headed pine sawfly (Neodiprion lecontei Fitch) is a common insect attacking pines in Ontario. Plantations red pine are almost invariably attacked from the time the trees have reached two to four feet in height. Periodically epidemic populations cause significant damage. The life history and habits of the species have heen described by Middleton (2) who states that this insect attacks practically all species of pine as bell as larch. Schaffner (3) also indicates that the larvae feed on a wide variety of pine and occasionally on other conifers. Red pine (Pinus resinosa Ait.) is undoubtedly the usual host, although in Ontario jack pine (Pinus banksiana Lamb.) is sometimes attacked. In 1946 evidence was secured to show that jack pine needles may be selected for oviposition even in an area where red pine foliage is plentiful. (Figure 1).


Geoderma ◽  
2014 ◽  
Vol 228-229 ◽  
pp. 182-191 ◽  
Author(s):  
Amanda K. Hodson ◽  
Howard Ferris ◽  
Allan D. Hollander ◽  
Louise E. Jackson

2008 ◽  
Vol 57 (1-6) ◽  
pp. 333-340 ◽  
Author(s):  
M. Ranger ◽  
K. K. Nkongolo ◽  
P. Michael ◽  
P. Beckett

Abstract Metal accumulation in soil and plant tissues has caused severe ecological damage in forest ecosystems in the Sudbury region. The main objective of the present study was to determine the levels of genetic diversity in jack and red pine populations growing in metal contaminated and uncontaminated areas. Newly introduced populations were compared to 40 to 60 old populations. For jack pine, the percentage of polymorphic loci (P %) ranged from 14.6% to 45.8% with a mean of 31.6%. Nei’s gene diversity (h) varied from 0.046 to 0.169 with an average of 0.100, and Shannon’s index (I) ranged from 0.070 to 0.250 with an average of 0.153. The level of genetic variation was much lower in the red pine populations. For this species, the level of polymorphic loci varied from 4.55% to 27.27%. The mean for Nei’s gene diversity and Shannon’s information index, were 0.034 and 0.053, respectively. The highest genetic diversity values were observed in new plantations being developed by the Sudbury reforestation program. Overall, the genetic distance among the Pinus banksiana populations revealed that all the populations analyzed were genetically close to each other. There was no association between metal accumulation and genetic diversity for both species.


Sign in / Sign up

Export Citation Format

Share Document