The association of young weevil-killed pine and spruce terminals with Phellinuspini in western Canada

1996 ◽  
Vol 26 (12) ◽  
pp. 2224-2226 ◽  
Author(s):  
Kenneth I. Mallett ◽  
David W. Langor

Terminals of jack pine (Pinusbanksiana Lamb.), lodgepole pine (Pinuscontorta Dougl. ex Loud. van latifolia Engelm.), and white spruce (Piceaglauca (Moench) Voss), killed by either Pissodesstrobi (Peck) or Pissodesterminalis Hopping, were sampled from 17 sites in Alberta, Saskatchewan, Manitoba, and the Northwest Territories. The weevil-killed terminals were examined for decay caused by Phellinuspini (Brot.:Fr.). Wood chips taken from the terminals were placed on agar media in an attempt to isolate P. pini. No decay was observed in the terminals. Of 192 isolations from freshly killed terminals, 32% were sterile. Phellinuspini was not isolated from any of the terminals. The predominant fungi found were Aureobasidiumpullulans (de Bary) Arn., Hormonemadematioides Lagerberg & Melin, and Phialemoniumdimorphosporum W. Gams & W.B. Cooke. Weevil-killed terminals from lodgepole pine and white spruce that had been dead for up to 6 years were sampled for the presence of P. pini. The fungus was not found in any of the decayed wood in the terminals, although several other unidentified Basidiomycete species were isolated.

2017 ◽  
Vol 47 (8) ◽  
pp. 1116-1122 ◽  
Author(s):  
Rongzhou Man ◽  
Pengxin Lu ◽  
Qing-Lai Dang

Conifer winter damage results primarily from loss of cold hardiness during unseasonably warm days in late winter and early spring, and such damage may increase in frequency and severity under a warming climate. In this study, the dehardening dynamics of lodgepole pine (Pinus contorta Dougl. ex. Loud), jack pine (Pinus banksiana Lamb.), white spruce (Picea glauca (Moench) Voss), and black spruce (Picea mariana (Mill.) B.S.P.) were examined in relation to thermal accumulation during artificial dehardening in winter (December) and spring (March) using relative electrolyte leakage and visual assessment of pine needles and spruce shoots. Results indicated that all four species dehardened at a similar rate and to a similar extent, despite considerably different thermal accumulation requirements. Spring dehardening was comparatively faster, with black spruce slightly hardier than the other conifers at the late stage of spring dehardening. The difference, however, was relatively small and did not afford black spruce significant protection during seedling freezing tests prior to budbreak in late March and early May. The dehardening curves and models developed in this study may serve as a tool to predict cold hardiness by temperature and to understand the potential risks of conifer cold injury during warming–freezing events prior to budbreak.


Botany ◽  
2016 ◽  
Vol 94 (2) ◽  
pp. 117-126 ◽  
Author(s):  
Rongzhou Man ◽  
Steve Colombo ◽  
Pengxin Lu ◽  
Qing-Lai Dang

Compared with the effects of spring frosts on opening buds or newly flushed tissues, winter freezing damage to conifers, owing to temperature fluctuations prior to budbreak, is rare and less known. In this study, changes in cold hardiness (measured based on electrolyte leakage and needle damage) and spring budbreak were assessed to examine the responses of four boreal conifer species — black spruce (Picea mariana (Mill.) B.S.P.), white spruce (Picea glauca) (Moench) Voss), jack pine (Pinus banksiana Lamb.), and lodgepole pine (Pinus contorta Dougl. ex. Loud.) — to different durations of experimental warming (16 °C day to –2 °C night with a 10 h photoperiod, except for night temperatures during November warming (+2 °C)). Seedlings showed increased responses to warming from November to March, while the capacity to regain the cold hardiness lost to warming decreased during the same period. This suggests an increasing vulnerability of conifers to temperature fluctuations and freezing damage with the progress of chilling and dormancy release from fall to spring. Both lodgepole pine and jack pine initiated spring growth earlier and had greater responses to experimental warming in bud phenology than black spruce and white spruce, suggesting a greater potential risk of frost/freezing damage to pine trees in the spring.


1974 ◽  
Vol 4 (4) ◽  
pp. 555-557 ◽  
Author(s):  
George W. Scotter

Specimens of jack pine (Pinusbanksiana Lamb.), Rocky Mountain lodgepole pine (Pinuscontorta spp. latifolia (Engelm.) Critchfield) and hybrids of those two species were collected in the South Nahanni and Flat Rivers region. Those collections extend the previously known range of pines within that region.


1992 ◽  
Vol 22 (8) ◽  
pp. 1124-1131 ◽  
Author(s):  
Bruce Downie ◽  
Ben S.P. Wang

The IDS (incubation–desiccation–separation) technique, designed to upgrade germinability and vigour of conifer seed lots, was tested on various seed lots of white spruce (Piceaglauca (Moench) Voss), lodgepole pine (Pinuscontorta var. latifolia Engelm.), and jack pine (Pinusbanksiana Lamb.). The effect on germinability of redrying separated seeds to storage moisture content (approx. 5% fresh weight) and of accelerated ageing was also investigated. Separation resulted in significant increases in germinability for four of five lodgepole pine, three of four jack pine, and two of five white spruce seed lots. Redrying usually had no significant effect on germinability of separated seeds, and its effect was not predictable. Accelerated ageing decreased the mean germinability of all seed lots and fractions. Although the mean index of ageing was usually not significantly different between the control and bottom fraction (live seeds) for any species, the surface fraction (dead and dying seeds) usually had a significantly higher index of ageing. The IDS technique is effective for upgrading the germinability of a portion of a seed lot of lodgepole pine and jack pine but must be modified if it is to work well with white spruce.


2006 ◽  
Vol 36 (4) ◽  
pp. 1006-1016 ◽  
Author(s):  
J P Brandt

While lodgepole pine dwarf mistletoe, Arceuthobium americanum Nutt. ex Engelm., is one of the most damaging pests of jack pine (Pinus banksiana Lamb.) in western Canada, no studies have examined the life cycle of this parasite in this pathosystem. Twenty-five jack pine trees in a plantation in Edmonton, Alberta, were inoculated with seeds of A. americanum in the fall of 1998 and 1999; these inoculants were monitored until the dwarf mistletoe plants that arose completed their life cycle. Ninety-two percent of inoculated seeds overwintered on their host. Seventy percent of these seeds germinated, mostly in May. Of these germinants, 69% developed holdfasts. Sixty-eight percent of germinants that developed holdfasts infected their host and produced shoots, primarily between July and August in the second season after inoculation. Of the 56 plants that developed from the 175 inoculations, 34 were pistillate plants and 19 were staminate plants, and 3 immature plants died because the host branch died. Pistillate plants flowered significantly earlier than staminate plants (4.1 vs. 4.7 years). Most pistillate plants produced seed in the fifth year, although one plant produced seed in 4 years. Thus, A. americanum probably has a 5-year life cycle on jack pine.


2020 ◽  
Vol 50 (5) ◽  
pp. 457-464 ◽  
Author(s):  
Felix O. Oboite ◽  
Philip G. Comeau

Understanding interactions between competition and climate in relation to their effects on individual tree growth is crucial to the development of climate-sensitive growth models required for modelling boreal forest succession in a changing climate. We used data from permanent growth and yield sample plots in western Canada and Alaska to investigate the impact of competition within a regional gradient of climatic conditions for lodgepole pine (Pinus contorta Douglas ex Loudon), jack pine (Pinus banksiana Lamb.), trembling aspen (Populus tremuloides Michx.), balsam poplar (Populus balsamifera L.), white spruce (Picea glauca (Moench) Voss), and black spruce (Picea mariana (Mill.) Britton, Sterns & Poggenb.). We characterized the effects of competition (basal area of spruce–fir, deciduous, and pine trees larger than the focal tree) and climate (mean annual temperature and precipitation) and their interactions on basal area growth of individual trees using linear mixed-effects models. Our results indicated that intraspecific competition had stronger effects on growth than interspecific competition and climate. Moreover, significant interactions between intraspecific competition and climate suggest that an increase in intraspecific competition will lead to a reduction in tree growth for warmer regions (lodgepole pine, trembling aspen, balsam poplar, and white spruce) and wetter regions (jack pine). The manner in which interspecific competition altered tree growth responses to climate was variable, depending on tree species and competition type. These results indicate that the relationships between growth and climate may differ according to the degree of competition and the structure of the stand.


1968 ◽  
Vol 44 (4) ◽  
pp. 11-15 ◽  
Author(s):  
L. Heger

Site-index curves were constructed from stem-analyses data with the help of linear regressions derived for relationships between site index (total height at BH age of 50 years, the independent variable) and total heights attained at the end of the previous nine 5-year periods. The method was tested for white spruce, black spruce, lodgepole pine and jack pine.


2011 ◽  
Vol 28 (3) ◽  
pp. 146-151 ◽  
Author(s):  
Alain Paquette ◽  
Jean-Pierre Girard ◽  
Denis Walsh

Abstract Although studies in the past have reported that the deeper planting of conifers has no effect on seedling performance, most planting guidelines in use today still recommend that seedlings be planted to the rootcollar. Past studies were mostly observational, used bareroot seedlings, and often reported early results from just one or two depths of planting treatments. Most of the results available regarding planting depth for boreal species are anecdotal, although they are planted by the hundreds of millions every year. The present study reports no short-term (1 year) or long-term (15 to 19 years) negative effect of planting depth on the survival and height and diameter growth of black spruce, white spruce, and jack pine seedlings over three large, replicated experiments in the boreal forest of eastern and northern Quebec (eastern Canada). Four different depth treatments were compared, from manual planting at the rootcollar to the deepest mechanical planting treatment at 10 cm or more, making this the largest, longest-lasting study of its kind. Although, as expected, important differences in growth were present between species, all three commonly planted conifers reacted similarly to the planting depth treatments (no effect). This result can in part be attributed to an almost perfect control of frost heaving in the deepest two treatments. Planting depth effects were assessed using analysis of variance, multiple Tukey honestly significant difference, and uncorrected pairwise one-tailed t-tests to increase the probability of detecting a negative effect. Absolute differences and effect sizes (generally small and often positive with greater depths) were also analyzed.


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