Growth of Engelmann Spruce (Picea engelmannii) Unaffected by Increased Snowpack

1974 ◽  
Vol 6 (1) ◽  
pp. 29 ◽  
Author(s):  
Howard L. Gary
2004 ◽  
Vol 59 (9-10) ◽  
pp. 641-648 ◽  
Author(s):  
Marek Mardarowicz ◽  
Dorota Wianowska ◽  
Andrzej L. Dawidowicz ◽  
Ryszard Sawicki

Abstract Terpenes emitted by conifer trees are generally determined by analysing plant extracts or essential oils, prepared from foliage and cones using steam distillation. The application of these procedures limits experiments to cut plant materials. Recently headspace techniques have been adopted to examine terpene emission by living plants. This paper deals with the application of solid-phase micro-extraction (SPME) for the analysis of terpenes emitted by conifers foliage of Engelmann spruce (Picea engelmannii), including its seedlings. The compositions of SPME extracts obtained for destroyed and non-destroyed old and juvenile spruce needles were compared with the compositions of essential oils and pressurised liquid extraction (PLE) extracts corresponding to the same plant materials. No substantial differences have been found in the qualitative terpene composition estimated by analysing essential oil and PLE and SPME extracts from non-destroyed old and juvenile foliage. The disintegration of spruce needles results in the formation of a significant amount of myrcene in the case of the old conifer foliage and non-terpenoic compounds in the case of juvenile conifer foliage. This phenomenon can be attributed to enzymatic reactions occurring in the destroyed plant cells.


1982 ◽  
Vol 60 (12) ◽  
pp. 2753-2761 ◽  
Author(s):  
Alan K. Knapp ◽  
William K. Smith

Although seedlings of Abies lasiocarpa are generally more abundant than those of Picea engelmannii in the understory of mature spruce–fir forests throughout the central and northern Rocky Mountains, little information exists concerning environmental or plant factors that may influence the establishment of these two conifers. Field measurements in the Medicine Bow Mountains of southeast Wyoming showed that seedlings of A. lasiocarpa had greater photosynthetic rates at low understory light levels and required lower levels of incident radiation for saturation of photosynthesis compared with those of P. engelmannii. However, both conifers occurred in understory locations where total daily solar radiation was equally low (<2 MJ∙m−2∙day−1) and thus, a lack of light did not appear to be responsible for the low number of P. engelmannii seedlings in the understory. In contrast, seedlings of P. engelmannii were substantially more abundant at locations with thinner litter layers compared with those of A. lasiocarpa. Also, laboratory studies showed that the smaller seeds of P. engelmannii germinated more rapidly and at lower temperatures than seeds of A. lasiocarpa although growth of tap roots on A. lasiocarpa seedlings was greater initially ([Formula: see text] longer in 2-week-old seedlings) as well as for 10-week-old seedlings (50% longer). The deeper penetrating tap root of A. lasiocarpa seedlings may enable this conifer to establish more abundantly on thick, rapidly drying litter layers that are characteristic of mature spruce–fir forests. In contrast, establishment of P. engelmannii seedlings may be limited to microsites without a thick litter layer such as disturbed areas or decomposing wood, where surface drying may occur more gradually throughout the summer. These results are discussed in terms of the potential effects of seedling establishment on the observed patterns in climax vegetation of central and northern Rocky Mountain subalpine forests.


1991 ◽  
Vol 6 (2) ◽  
pp. 36-38 ◽  
Author(s):  
Scott D. Roberts ◽  
James N. Long

Abstract Containerized Engelmann spruce (Picea engelmannii) seedlings were treated with different nursery storage methods, planting dates, and amounts of overstory shelter after planting. Third-year survival of seedlings stored in refrigeration did not differ from that of seedlings maintained in a lathhouse prior to planting. Survival of seedlings planted in mid-June was about 70% compared to 48% for seedlings planted in late July. Survival was only 52% within strip shelterwood units and more than 72% in the more protected environment of uniform shelterwood units. Seedlings within strip shelterwood units were slightly taller after 3 years than those under a uniform shelterwood. West. J. Appl. For. 6(2):36-38.


2020 ◽  
Vol 55 (3) ◽  
pp. 301-309
Author(s):  
Christopher J. Fettig ◽  
A. Steven Munson ◽  
Donald M. Grosman ◽  
Darren C. Blackford

Abstract Bark beetles are important disturbance agents in coniferous forests, and spruce beetle, Dendroctonus rufipennis (Kirby) (Coleoptera: Curculionidae), is one of the more notable species causing landscape-level tree mortality in western North America. We evaluated the efficacy of bole injections of emamectin benzoate (TREE-äge®; Arborjet Inc., Woburn, MA) alone and combined with propiconazole (Alamo®; Syngenta Crop Protection Inc., Wilmington, DE) for protecting Engelmann spruce, Picea engelmannii Parry ex Engelmann (Pinales: Pinaceae), from mortality attributed to colonization by D. rufipennis. Two injection periods in 2013 (the spring and fall of the year prior to trees first being challenged by D. rufipennis in 2014) and distributions of injection points (7.6- and 15.2-cm spacings) were evaluated. Tree mortality was monitored over a 3-yr period (2014–2017). Emamectin benzoate injected in spring at a narrow spacing (7.6 cm) was the only effective treatment. Two (but not three) field seasons of protection can be expected with a single injection of this treatment. We discuss the implications of these and other results regarding the use of emamectin benzoate and propiconazole for protecting western conifers from mortality attributed to bark beetles, and provide suggestions for future research. A table summarizing the appropriate timing of treatments in different bark beetle/host systems is provided.


1970 ◽  
Vol 48 (5) ◽  
pp. 851-853 ◽  
Author(s):  
Frank Ronco

Shade-tolerant Engelmann spruce (Picea engelmannii Parry) seedlings generally became chlorotic when exposed to direct sunlight under several different growing conditions, whether grown in pots, in plantations, or in transplant beds at high or low elevations. Shaded seedlings under the same growing conditions remained a normal green color. Chlorosis was attributed to solarization, not to nitrogen deficiency. That conclusion was supported by the fact that the nitrogen content of shaded and unshaded seedlings was similar regardless of the growing conditions.


2006 ◽  
Vol 84 (7) ◽  
pp. 1129-1141 ◽  
Author(s):  
W.L Strong ◽  
L.V. Hills

White spruce ( Picea glauca (Moench) Voss) and Engelmann spruce ( Picea engelmannii Parry ex Engelm.) seed-cones from 676 sites in Canada and the northern United States were analyzed to determine the degree and spatial extent of interspecific hybridization. Fifteen cone-scale variables were analyzed, with percent free-scale and scale shape considered best for differentiating these taxa. The results show that putative Engelmann spruce and their hybrids occur mostly in the vicinity of the Rocky Mountains. Putative white spruce occurs across Canada east of the Rocky Mountains, whereas white × Engelmann hybrids occur eastward to Manitoba and northward to 68° latitude in northwest Canada. To explain the occurrence of the latter taxon hundreds of kilometres from an Engelmann spruce pollen source, it is hypothesized that palaeohybridization occurred during the Wisconsinan glacial period, probably in the southern Montana – Wyoming – Black Hills (South Dakota) region, with the resulting hybrids spreading north and northeastward into interior Canada following the retreat of the Laurentide glacier. White and Engelmann spruce have morphologically distinct cone-scales, whereas their hybrids have intermediate characteristics. An emended species ( Picea albertiana ) and two subspecies (P. albertiana subsp. albertiana and P. albertiana subsp. ogilviei) are proposed to account for morphological intermediates between the parent species.


2019 ◽  
Vol 112 (5) ◽  
pp. 2253-2261 ◽  
Author(s):  
E Matthew Hansen ◽  
A Steven Munson ◽  
David Wakarchuk ◽  
Darren C Blackford ◽  
Andrew D Graves ◽  
...  

AbstractWe tested 3-methyl-2-cyclohexen-1-one (MCH) and novel semiochemicals as potential spruce beetle (Dendroctonus rufipennis Kirby) (Coleoptera: Curculionidae, Scolytinae) repellents over multiple years in Utah and Colorado trapping bioassays. MCH is a known spruce beetle repellent and our testing revealed Acer kairomone blend (AKB) and isophorone plus sulcatone as repellents. We subsequently tested these semiochemicals for area and single tree protection to prevent spruce beetle attacks at locations in Utah, Colorado, Wyoming, New Mexico, and Alaska. Individual tree protection trials found MCH–AKB provided significant protection against spruce beetle attacks in the southern Rocky Mountains but not in Alaska. Adding sulcatone or doubling MCH–AKB pouches did not further enhance protection. A degree of protection was extended to spruce at least 10 m distant from the repellents, including in Alaska. Tree diameter was not a significant covariate among treated trees but was positively correlated with the probability of infestation for surrounding spruce. In area protection trials, spruce in control plots were 2.4 times more likely to be in a higher severity attack class compared with spruce in plots treated with MCH–AKB pouches deployed at 30 sets per hectare. Tree diameter had a significant, positive relationship to the probability of infestation. We found MCH–AKB to offer a high degree of protection against beetle attack in Engelmann spruce (Picea engelmannii Parry ex Engelm.) (Pinales: Pinaceae) (Picea engelmannii Parry ex Engelm.) (Pinales: Pinaceae), especially for single tree protection (66% of control trees were strip- or mass-attacked compared with 6% of repellent-treated trees). AKB requires registration and labeling, however, before this economical and environmentally benign semiochemical can be used operationally.


1999 ◽  
Vol 29 (6) ◽  
pp. 761-767 ◽  
Author(s):  
J R Nault ◽  
J F Manville ◽  
T S Sahota

White spruce (Picea glauca (Moench) Voss) and Engelmann spruce (Picea engelmannii Parry) parent trees were selected that were rated as highly resistant or highly susceptible to white pine weevil (Pissodes strobi Peck) attack, based upon attack measurements on their open-pollinated progeny. For each parent, levels of terpenes or other volatiles in leaf and bark were highly correlated within ramets and highly variable within progeny. For the ramets, levels of individual terpenes could not be used to predict resistance class because of their large variability. A multivariate model developed using the terpenes showing the greatest differences between resistant classes was found to predict the resistance levels of the original ortets well, with 15 of 16 parent trees correctly predicted using either leaf or bark chemicals. These models failed to predict the resistance level of the open-pollinated progeny. Discriminant analysis was also attempted by dividing the ramet data into independent sets and using each set to predict the other. Again, prediction was no better than chance. We conclude that there is no merit in using terpenes as a selection tool to find resistant genotypes amongst white and Engelmann spruce populations.


1996 ◽  
Vol 72 (2) ◽  
pp. 193-198 ◽  
Author(s):  
K. Klinka ◽  
H. Y. H. Chen ◽  
Q. Wang ◽  
R. E. Carter

Stem analysis data from even-aged Engelmann spruce (Picea engelmannii Parry ex Engelm.) and subalpine fir [Abies lasiocarpa (Hook.) Nutt.] stands on zonal sites in the Engelmann Spruce—Subalpine Fir biogeoclimatic zone of British Columbia were used to examine the relationships of site index and height growth and elevation, latitude, and longitude. Elevation and latitude were found to be strongly negatively correlated with site index of both study species. Spruce site index (bh age 50) was predicted to decrease 2.9 m and fir site index 2.5 m with every 100 m and 1° increase in elevation and latitude, respectively; however, (i) site index of both species appeared to decline faster with increasing latitude than elevation, and (ii) decrease appeared to be faster for spruce than for fir. Comparison of height growth curves for stands on zonal and azonal sites with similar site index from different elevations and latitudes suggested that there are probably inconsequential differences between the shape of curves for either species. These findings imply that (i) subalpine fir is better adapted to subalpine boreal climates than Engelmann spruce and (ii) development of polymorphic site index curves for estimating site index of both species may be appropriate. Key words: elevation, latitude, longitude, site index, height growth, Abies lasiocarpa, Picea engelmannii, Engelmann Spruce—Subalpine Fir zone


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