Journal articles: 'Engelmann'

1

Rajora, Om P., and Bruce P. Dancik. "Population genetic variation, structure, and evolution in Engelmann spruce, white spruce, and their natural hybrid complex in Alberta." Canadian Journal of Botany 78, no. 6 (June 1, 2000): 768–80. http://dx.doi.org/10.1139/b00-054.

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Genetic variation, structure, and evolution of 12 populations of putative Engelmann spruce (Picea engelmanii Parry), white spruce (Picea glauca (Moench) Voss), and Engelmann - white spruce natural hybrids from the sympatric areas and two populations of white spruce from the allopatric areas in Alberta were examined using 23 allozyme loci coding for 13 enzymes in needles. Although most of the alleles were widespread, unique alleles were found in 9 of the 14 populations. No species-specific allele was observed. However, allele frequency differences were observed between the putative Engelmann and white spruce populations at a number of loci. Frequencies of 13 alleles showed significant correlation with altitude, those of 11 alleles showed correlation with latitude, and those of 3 alleles showed correlation with longitude. On average, 66.2% (99% criterion) of the loci were polymorphic, the number of alleles per locus was 1.88, the number of alleles per polymorphic locus was 2.88, and the observed and expected heterozygosities were 0.063 and 0.184, respectively. Genetic variability of allopatric white spruce, putative Engelmann, sympatric white spruce, and hybrid populations was quite comparable. The mean FST estimate was 0.123 for the total populations. Canonical discriminant functions separated four putative Engelmann spruce populations from the fifth putative Engelmann spruce population and from the allopatric and sympatric white spruce and sympatric putative hybrid populations. A cluster analysis from genetic distances generally separated allopatric and sympatric white spruce populations from the putative Engelmann spruce and hybrid populations. A Wagner tree of the 14 populations produced two main branches; one branch consisting of two allopatric and two sympatric white spruce and one putative hybrid populations, and another branch consisting of the remaining nine spruce populations representing putative Engelmann spruce, putative hybrids, and sympatric white spruce. Putative hybrids showed lower distances to white spruce from the canonical discriminant analysis, whereas they showed lower distances to putative Engelmann spruce from the genetic distance analysis. High allozyme genetic identities between putative Engelmann and white spruce and allelic differentiation related to altitude in Alberta suggest that Engelmann spruce could at best be considered as a subspecies of Picea glauca, with white spruce named as Picea glauca ssp. glauca and Engelmann spruce named as Picea glauca ssp. engelmannii.Key words: Picea glauca, Picea engelmannii, biosystematics, natural hybridization, species differentiation, genetic divergence.

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2

Tanaka, Yasuomi, L. M. Harper, and N. J. Kleyn. "Seed Stratification of Engelmann Spruce and Lodgepole Pine: The Effect of Stratification Duration and Timing of Surface-drying." Forestry Chronicle 62, no. 3 (June 1, 1986): 147–51. http://dx.doi.org/10.5558/tfc62147-3.

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Based on the speed and completeness of laboratory germination and nursery bed emergence, the present study showed that for both Engelmann spruce (Picea engelmannii [Parry] Engelmann) and lodgepole pine (Pinus contorta Dougl.): (1) longer stratification generally improved the rate, and in some cases completeness, of germination more so under a cool temperature (15 °C/5 °C) regime than under a warm, standard temperature (30 °C/20 °C) regime emphasizing its importance for early spring outdoor sowing under suboptimal germination temperatures, (2) for a given stratification period, surface-drying at the end of stratification was at least as effective as surface-drying prior to or during stratification, and (3) stratification periods of 6 weeks or longer were generally the most effective. A 6- to 8-week stratification with seeds surface-dried at the end of stratification is recommended for nursery sowing of both species. Key Words: stratification, pinus contorta, Picea engelmanni, laboratory germination, nursery bed emergence.

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3

Ledig, F. Thomas, Paul D. Hodgskiss, and David R. Johnson. "The structure of genetic diversity in Engelmann spruce and a comparison with blue spruce." Canadian Journal of Botany 84, no. 12 (December 2006): 1806–28. http://dx.doi.org/10.1139/b06-106.

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Genetic diversity and genetic structure in Engelmann spruce (Picea engelmannii Parry ex Engelm.) were interpreted with respect to the effects of glacial and interglacial displacement and compared with patterns in blue spruce (Picea pungens Engelm.), which occupies a range well south of the last glacial front. On average, Engelmann spruce populations were polymorphic at 80% of 24 isozyme loci, with 2.4 alleles per locus and expected heterozygosity of 0.255. The respective means for four populations of blue spruce were 42.7%, 1.6 alleles, and 0.138. Of total diversity, 14.7% was among populations in Engelmann spruce and 8.6% in blue spruce. In Engelmann spruce, numbers of alleles increased from south to north. Recent bottlenecks were indicated in the three southernmost populations of Engelmann spruce and in the northernmost population of blue spruce. Cluster analysis divided Engelmann spruce into a northern group and a Southwestern group; however, populations from Utah were distributed among both clusters. Genetic distance was correlated with geographic distance between northern populations but not between Southwestern populations, where drift predominated over gene flow. In two Engelmann spruce populations from Utah, multilocus outcrossing rates were 0.951 (±0.016) and 0.940 (±0.071). At Flys Peak, Arizona, the southernmost location of Engelmann spruce, outcrossing was also high, 0.899 (±0.017). Thus, inbreeding coefficients observed for parental (–0.104 to 0.047) and filial (0.011 to 0.026) generations were low. Although Engelmann spruce seemed genetically robust, the evidence of bottlenecks in the southern extreme of its range suggested future problems in an era of global warming.

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4

Simão, Lívia Mathias. "A propósito das consciências: diálogo com Arno Engelmann." Paidéia (Ribeirão Preto) 12, no. 22 (2002): 103–6. http://dx.doi.org/10.1590/s0103-863x2002000100011.

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Este texto é resultado de um exercício de reflexão, desde a ótica semiótico-construtivista, a respeito de alguns aspectos centrais das formulações teóricas de Arno Engelmannn sobre consciência. Inicialmente é feita uma síntese das proposições de Engelmann sobre o tema, consideradas centrais para esta reflexão. A seguir, são indicadas, em contrapartida, algumas proposições nucleares do construtivismo semiótico-cultural, com respeito à relação sujeito-realidade, que podem estabelecer diálogo com as proposições engelmanianas, anteriormente destacadas. Finalmente, são colocadas algumas questões a respeito da abordagem de Engelmann à consciência, advindas desse diálogo.

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5

Klinka, K., H. Y. H. Chen, Q. Wang, and R. E. Carter. "Height growth–elevation relationships in subalpine forests of interior British Columbia." Forestry Chronicle 72, no. 2 (April 1, 1996): 193–98. http://dx.doi.org/10.5558/tfc72193-2.

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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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6

Strong, W. L., and L. V. Hills. "Taxonomy and origin of present-day morphometric variation in Picea glauca (×engelmannii) seed-cone scales in North America." Canadian Journal of Botany 84, no. 7 (July 2006): 1129–41. http://dx.doi.org/10.1139/b06-071.

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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.

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7

Owens, John N., Sheila J. Simpson, and Guy E. Caron. "The pollination mechanism of Engelmann spruce (Picea engelmannii)." Canadian Journal of Botany 65, no. 7 (July 1, 1987): 1439–50. http://dx.doi.org/10.1139/b87-199.

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The pollination mechanism of Picea engelmannii (Parry) was studied on small potted scions under natural conditions and in controlled environment chambers. Six stages of conelet development were recognized and related to pollen receptivity. Cone-lets appeared receptive for about 2 weeks but were actually receptive for only about 1 week. Secretory droplets appearing on the micropylar arms collected pollen for several days before pollination drops formed. Pollination drops formed acropetally in the conelet and only once from each ovule. Pollination caused rapid recession of the pollination drop, whereas the drop remained for several days on unpollinated ovules. There was some decrease in size of pollination drops during midday and reemergence the following night. Pollination drops were secreted by the nucellar tip in a manner similar to nectaries. Secretory cells collapsed following secretion. The drop contained 4.3% glucose and 3.8% fructose but no sucrose. High humidity increased the longevity and decreased the diurnal fluctuation in size of pollination drops. Conelets from trees with low leaf water potential developed more slowly and produced smaller and more viscous pollination drops. Cones averaged 103 ovuliferous scales, 90% of which were fertile. However, usually less than 50% of the potential seed set was achieved. One of the major causes for low seed set is inadequate pollination. A better understanding of the pollination mechanism and the receptive period may improve seed efficiency in controlled and supplemental mass pollinations.

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8

Stansfield, W. F., J. P. McTague, and R. Lacapa. "Dominant Height and Site Index Equations for Douglas-Fir and Engelmann Spruce in East-Central Arizona." Western Journal of Applied Forestry 7, no. 2 (April 1, 1992): 40–44. http://dx.doi.org/10.1093/wjaf/7.2.40.

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Abstract Dominant height and site index equations were constructed for Douglas-fir (Pseudotsuga menziesii var. glauca) and Engelmann spruce (Picea engelmannii) on the Fort Apache Indian Reservation, located in east-central Arizona. An indirect parameter prediction method was utilized to develop the equations from stem analysis data. The dominant height equation for Douglas-fir is a function of site index, age, habitat type groups, and soil texture groups. The Engelmann spruce dominant height equation is a function of only site index and age. Site index may be calculated directly by inverting the dominant height equations. West. J. Appl. For. 7(2):40-44.

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9

Shea, Kathleen L. "Segregation of allozyme loci in megagametophytes of Engelmann spruce and subalpine fir." Genome 30, no. 2 (April 1, 1988): 103–7. http://dx.doi.org/10.1139/g88-018.

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Segregation ratios and linkage of 10 allozyme loci were examined in haploid megagametophytes obtained from natural populations of Engelmann spruce (Picea engelmannii) and subalpine fir (Abies lasiocarpa) in the Colorado Front Range. For data pooled over trees, the 1:1 segregation ratio expected at Mendelian loci was obtained for five polymorphic loci in 32 Engelmann spruce trees and for seven polymorphic loci in 40 subalpine fir trees. The Gdh and Idh loci in spruce were very tightly linked: no recombinants were detected among 60 megagametophytes of trees heterozygous for both loci. In fir only the Aco and Pgm-1 loci were linked, with an estimated recombination rate of 0.317 ± 0.073. The low levels of among-tree heterogeneity and of segregation distortion found in these populations suggest that reliable estimates of both genetic variation and outcrossing rates can be obtained using allozyme data from these wind-pollinated species.Key words: segregation, linkage, allozymes, Engelmann spruce, subalpine fir.

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10

Varga, Pál, and Karel Klinka. "Structure of high-elevation, old-growth stands in west-central British Columbia." Canadian Journal of Forest Research 31, no. 12 (December 1, 2001): 2098–106. http://dx.doi.org/10.1139/x01-148.

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We described quantitatively the height distributions of three high-elevation, old-growth stands in the Engelmann Spruce Subalpine Fir zone of west-central British Columbia. The stands were composed of subalpine fir (Abies lasiocarpa (Hook.) Nutt.), with very few Engelmann spruce (Picea engelmannii Parry ex Engelm.) trees; had a two-storied canopy; and were multiaged. The height distributions were quantified by fitting curves to the cumulative frequency distributions. The diameter distributions of the study stands were reverse-J shaped and similar to those of other old-growth Engelmann spruce subalpine fir stands in the Pacific Northwest; however, the height distributions were different, indicating the presence of two canopy layers. We suggest that high-elevation, subalpine boreal, old-growth stands composed of shade-tolerant tree species may display a modal height distribution instead of a reverse-J shape. This structural pattern is suggestive of the transition between the gap-phase and tree-island regeneration models and of the cyclic mode of succession.

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11

Rehfeldt, Gerald E. "Adaptation of Picea engelmannii populations to the heterogeneous environments of the Intermountain West." Canadian Journal of Botany 72, no. 8 (August 1, 1994): 1197–208. http://dx.doi.org/10.1139/b94-146.

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Seedlings from 104 natural populations of Engelmann spruce (Picea engelmannii) and 10 blue spruce (Picea pungens) populations from the Intermountain West, U.S.A., were compared in common gardens. Comparisons involved 16 characters that described growth, development, and cold hardiness plus nine monoterpenes. Canonical discriminant analyses detected one population of blue spruce that had been misidentified, readily separated populations of blue and Engelmann spruce, suggested that three Southwest populations differed markedly from Intermountain populations of Engelmann spruce, but identified no Intermountain populations that reflected introgression with blue spruce. Genetic differences were detected among populations of Engelmann spruce for 16 of the morphometric characters, and multiple regression models accounted for as much as 70% of the variance among populations. The regressions described genetic variation occurring along clines that were dominated by elevational and latitudinal effects. The slope of the clines, however, was relatively gentle; populations located within the same physiographic province must be separated by at least 420 m in elevation before genetic differentiation becomes a reasonable possibility. By providing a means for assessing the degree by which similar genotypes recur across the landscape, the regression models have direct practical application in programs ranging from land management to conservation biology. Key words: population differentiation, genetic variation, ecological genetics.

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12

Brown, Peter M., Wayne D. Shepperd, Stephen A. Mata, and Douglas L. McClain. "Longevity of windthrown logs in a subalpine forest of central Colorado." Canadian Journal of Forest Research 28, no. 6 (June 1, 1998): 932–36. http://dx.doi.org/10.1139/x98-059.

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The number of years since tree death for wind-thrown logs of lodgepole pine (Pinus contorta var. latifolia Engelm.) and Engelmann spruce (Picea engelmannii Parry) was used to examine the longevity of this component of coarse woody debris in an old-growth subalpine forest in the central Rocky Mountains. Death dates of downed logs were determined by dendrochronological cross-dating methods. We were able to determine death dates for 73 logs from both species, the oldest being a lodgepole pine dead 139 years ago. Sound lodgepole pine and Engelmann spruce logs lying on the ground persisted for many decades with a majority of their volume intact. No difference was seen in decay classes of logs collected from two primary study sites on opposite (north and south) exposures. There was also no significant difference in decay classes between the two species, although lodgepole pine logs were in general older than Engelmann spruce logs within any decay class. There was little decrease in the specific gravity of wood remaining in logs with time, although there was a corresponding greater loss of wood volume.

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13

DeLong, Craig, and Del Meidinger. "Ecological variability of high elevation forests in central British Columbia." Forestry Chronicle 79, no. 2 (April 1, 2003): 259–62. http://dx.doi.org/10.5558/tfc79259-2.

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High-elevation, late-successional forests over much of British Columbia are dominated by Engelmann spruce (Picea engelmannii Parry ex. Engelm.) and subalpine fir (Abies lasiocarpa (Hook.) Nutt.). Throughout the range of these forests, however, there is a wide variation in natural disturbance and successional dynamics as influenced by diverse climate and topography. We divided these high elevation forests into four groups arranged along a regional climatic gradient that affects forest composition, structure and disturbance regime. For each, we describe the climate, topography, major vegetation, and natural disturbance dynamics. We suggest that management practices reflect the ecological variability demonstrated for these high elevation forests. Key words: high elevation forests, ecological variability, natural disturbance dynamics, vegetation, Engelmann spruce, subalpine fir, British Columbia, climate, topography

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14

Shea, Kathleen L. "Genetic variation between and within populations of Engelmann spruce and subalpine fir." Genome 33, no. 1 (February 1, 1990): 1–8. http://dx.doi.org/10.1139/g90-001.

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The genetic structure of Engelmann spruce (Picea engelmannii) and subalpine fir (Abies lasiocarpa) in two adjacent sites in the Colorado Front Range was examined using allozyme data from 21 loci in spruce and 18 loci in fir. The genetic diversity measures of alleles per locus, percent loci polymorphic, and mean heterozygosity did not differ significantly between or within species. However, the observed heterozygosity (0.126 spruce, 0.081 fir) values suggest that Engelmann spruce is more genetically variable than subalpine fir. Mean inbreeding coefficients were twice as high in fir as in spruce (FIS = 0.154 spruce, 0.341 fir). There were significant differences in allele frequencies in both species between and within sites, and among age-classes, with spatial differences greater than temporal differences. F-statistics showed greater genetic differentiation within (FST = 2.3–2.6% spruce, 2.0–2.8% fir) than between sites (FST = 1.7% spruce, 1.3% fir). Both species had higher FST and genetic distance values, yet lower FIS values, for spatial subdivisions within rather than between sites. This pattern suggests that the size of a spatial subdivision, where maximum gene flow is 54 m, approximates the size of the largest panmictic unit. In contrast with studies on other conifers, these results suggest that factors such as differential selection pressures, seed dispersal patterns, and clumped spatial distribution have resulted in genetic differentiation at the microhabitat level in Engelmann spruce and subalpine fir.Key words: genetic variation, genetic structure, allozymes, Engelmann spruce, subalpine fir, microgeographic differentiation.

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15

Chen, Han Y. H., and Karel Klinka. "Height Growth Models for High-Elevation Subalpine Fir, Engelmann Spruce, and Lodgepole Pine in British Columbia." Western Journal of Applied Forestry 15, no. 2 (April 1, 2000): 62–69. http://dx.doi.org/10.1093/wjaf/15.2.62.

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Abstract To estimate potential productivity of the high-elevation Engelmann Spruce and Subalpine Fir (ESSF) zone of British Columbia forests, the height growth models developed from low-elevation forests are currently used to estimate site indices of subalpine fir (Abies lasiocarpa), Engelmann spruce (Picea engelmannii), and lodgepole pine (Pinus contorta). Whether these models are adequate to describe height growth of high-elevation forests is of concern. We sampled a total of 319 naturally established, even-aged, and undamaged stands with breast height age ≥50 yr (165 for subalpine fir, 87 for Engelmann spruce, and 67 for lodgepole pine) ranging widely in climate and available soil moisture and nutrients. In each sampled stand, three dominant trees were destructively sampled for stem analysis. Height growth models developed from fitting data to a conditioned logistic function explained > 97% variation in height for all three study species. Examined by residual analysis, no models showed lack of fit. These models provided more accurate estimates of site index than the currently used models developed from low-elevation stands or different species. It is recommended that the models developed in this study be applied to estimate site index of the three species in the ESSF zone in British Columbia. West. J. Appl. For. 15(2):62-69.

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16

Jacobs, Douglass F., and Klaus Steinbeck. "Tree Shelters Improve the Survival and Growth of Planted Engelmann Spruce Seedlings in Southwestern Colorado." Western Journal of Applied Forestry 16, no. 3 (July 1, 2001): 114–20. http://dx.doi.org/10.1093/wjaf/16.3.114.

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Abstract Shade-tolerant Engelmann spruce (Picea engelmannii) is a difficult species to reforest successfully in the high-elevation spruce-fir forests of the Rocky Mountains. This study investigated the use of plastic tree shelters as a form of shade protection and a means to improve the growth and survival of planted Engelmann spruce seedlings in southwest Colorado. A total of 1500 seedlings were planted into a 48 ha clearcut site at an average elevation of 3273 m. Treatments included four different colors of tree shelters and a control where seedlings were planted using the traditional shading method. This consisted of shading the seedlings using logging slash, stumps, and vegetation within the site. After two growing seasons, survival was 58% for the control treatment and ranged from 95 to 99% in the lighter three shelter color treatments. The darkest shelter color resulted in 95% mortality after the first growing season. Both height and diameter growth of surviving seedlings were significantly greater in the lightest two shelter color treatments as compared to the control treatment. These results indicate that tree shelters may provide an effective method of improving high-elevation Engelmann spruce reforestation programs. West. J. Appl. For. 16(3):114–120.

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17

Ferguson, Dennis E. "Allelopathic potential of western coneflower (Rudbeckia occidentalis)." Canadian Journal of Botany 69, no. 12 (December 1, 1991): 2806–8. http://dx.doi.org/10.1139/b91-351.

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Water extracts and volatiles from western coneflower (Rudbeckia occidentalis Nutt.) were tested for allelopathic potential under controlled laboratory conditions. Test species were lettuce (Lactuca sativa, Lilly Miller Great Lakes), lodgepole pine (Pinus contorta Dougl. ex Loud.), and Engelmann spruce (Picea engelmannii Parry ex Engelm.) using four treatments (leaves–stems, solid caudex, rotting caudex, and control). Water extracts reduced radicle lengths of seeds but had little effect on germination. Volatiles reduced or delayed germination but had little effect on radicle lengths of germinants. Key words: phytotoxin, Pinus contorta, Picea engelmannii.

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Wingfield, Michael J., Thomas C. Harrington, and Halvor Solheim. "Two species in the Ceratocystis coerulescens complex from conifers in western North America." Canadian Journal of Botany 75, no. 5 (May 1, 1997): 827–34. http://dx.doi.org/10.1139/b97-092.

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Two species of Ceratocystis are described from western North America. Ceratocystis rufipenni Wingfield, Harrington, & Solheim is associated with the North American spruce bark beetle Dendroctonus rufipennis infesting both Engelmann spruce (Picea engelmannii Parry) and white spruce (Picea glauca (Moench) Voss) in British Columbia. This fungus is a primary component of the bark beetle mycota and has a relatively high degree of virulence to Engelmann spruce. Ceratocystis douglasii (Davidson) Wingfield & Harrington was previously described as Endoconidiophora coerulescens f. douglasii. It is common on Douglas-fir lumber in western North America where it causes blue stain. Both fungi grow optimally at low temperatures and produce perithecia only after extended incubation under refrigeration. Ceratocystis rufipenni produces conidiophores mostly in association with perithecia, whereas conidia and conidiophores of C. douglasii are produced abundantly on wood and agar. Key words: Ceratocystis, Chalara, Dendroctonus, Ophiostoma, bark beetle – fungus interactions, symbiosis.

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Gupta, Sheena, Sanober Wasim, Neerul Pandita, and BP Kalra. "Camurati Engelmann Syndrome." International Journal of Contemporary Medicine 4, no. 1 (2016): 29. http://dx.doi.org/10.5958/2321-1032.2016.00006.1.

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Bellew, Neil, and Georg Wagener. "Camurati-Engelmann disease." South African Journal of Radiology 15, no. 1 (February 21, 2011): 20. http://dx.doi.org/10.4102/sajr.v15i1.343.

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Camurati-Engelmann disease (CED), or progressive diaphyseal dysplasia, is a rare sclerosing dysplasia of which 250 cases have been described in the English literature. The disease affects one in a million people and is autosomal dominant with variable penetrance. It was initially described by Cockayne in 1920; Camurati was the first to suggest its hereditary nature in 1922. A single case of muscular wasting and marked bone involvement was reported by Engelmann in 1929. As the name suggests, there is progressive hyperostosis and predominant involvement of the diaphyses. The onset of the disease is usually during childhood; patients usually present by puberty and usually before age 30, with limb pain, muscular weakness, waddling gait and easy fatigue. Other symptoms and signs may include delayed growth, reduced muscle mass, anorexia and enlargement of the arms and legs. Systemic manifestations of hepatosplenomegaly, bone marrow dysfunction (anaemia and leucopaenia) and delayed sexual development occasionally occur. In a few patients, abnormal values of bone resorption and formation have been described. Radiologically, the hallmark of the disorder is bilateral, symmetrical cortical thickening of the diaphyses of the long bones on both the periosteal and endosteal sides of the diaphyses. In decreasing order of frequency, the tibia, femur, fibula, humerus, ulna and radius are affected. CED results from disturbance of intramembranous ossification (Fig.1) affecting the long bones, calvaria, mandible and facial bones. There are a few reported cases of involvement of the skull base (a site of endochondral ossification), but these occur in advanced stages.

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de Bonilla Damiá, Álvaro, and Francisco Javier García Gómez. "Camurati-Engelmann Disease." Reumatología Clínica (English Edition) 13, no. 1 (January 2017): 48–49. http://dx.doi.org/10.1016/j.reumae.2015.12.004.

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Pathmanathan, S., Noel P. Somasundaram, Anil De Silva, J. Jeyakumar, MV Perera, and Anandi Samarasekara. "Camurati-Engelmann disease." Sri Lanka Journal of Diabetes Endocrinology and Metabolism 1, no. 1 (March 25, 2012): 54. http://dx.doi.org/10.4038/sjdem.v1i1.4207.

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Hurst, J. Willis, W. Bruce Fye, and Heinz-Gerd Zimmer. "Theodor Wilhelm Engelmann." Clinical Cardiology 29, no. 11 (November 2006): 518–20. http://dx.doi.org/10.1002/clc.4960291113.

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Van Hul, Wim, Eveline Boudin, Filip M. Vanhoenacker, and Geert Mortier. "Camurati–Engelmann Disease." Calcified Tissue International 104, no. 5 (February 5, 2019): 554–60. http://dx.doi.org/10.1007/s00223-019-00532-1.

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Brunet, Bryan M. T., Anina E. Hundsdoerfer, and Felix A. H. Sperling. "Identification and ecological characterisation of Choristoneura occidentalis (Lepidoptera: Tortricidae) populations in southwestern Alberta, Canada." Canadian Entomologist 145, no. 5 (August 7, 2013): 521–28. http://dx.doi.org/10.4039/tce.2013.40.

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AbstractThe western spruce budworm, Choristoneura occidentalis Freeman (Lepidoptera: Tortricidae), is an important pest of western North American coniferous forests, where its principal larval host is Rocky Mountain Douglas-fir, Pseudotsuga menziesii subspecies glauca (Beissner) Murray (Pinaceae). In southwestern Alberta, Canada, populations were recently discovered feeding on an unconventional host, an Engelmann spruce, Picea engelmannii Parry ex. Engelmann × white spruce, Picea glauca (Moench) Voss hybrid (Pinaceae), in a transition zone between the two major forest types characterised by these conifer species. We use molecular evidence to verify the species identity of outbreaking Choristoneura populations collected from Douglas-fir and hybrid spruces in southwestern Alberta in 2009, and characterise the larval and male moth phenology. Both mitochondrial and microsatellite markers confirmed these populations as C. occidentalis, but admixture with Choristoneura fumiferana (Clemens) (Lepidoptera: Tortricidae) was detected in some individuals. Few differences associated with separate host trees were evident in the phenology of larvae and the flight period of male moths.

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Kiss, G. K. "Engelmann × Sitka spruce hybrids in central British Columbia." Canadian Journal of Forest Research 19, no. 9 (September 1, 1989): 1190–93. http://dx.doi.org/10.1139/x89-178.

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Several crosses of Engelmann × Engelmann and Engelmann × Sitka spruce (one parent) were studied. Average crossability of the latter was 24.5%. Average heights of the pure Engelmann and the hybrid spruce were 361.6 and 183.6 cm, respectively, at plantation age 13 (16 years from seed). The difference in height appeared to be the result of repeated winter kill of large proportions of the previous summer's growth. Age to age correlations for total tree heights at 3–7 and 7–13 years old were highly significant. Based on these results, Engelmann × Sitka spruce hybrids are not recommended for reforestation purposes in the north-central interior of British Columbia. However, there are indications that preselecting better genotypes may improve the performance of the resulting hybrids; thus, further research in this direction is warranted.

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Burr, Karen E., Stephen J. Wallner, and Richard W. Tinus. "Heat Tolerance, Cold Hardiness, and Bud Dormancy Relationships in Seedlings of Selected Conifers." Journal of the American Society for Horticultural Science 118, no. 6 (November 1993): 840–44. http://dx.doi.org/10.21273/jashs.118.6.840.

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Greenhouse-cultured, container-grown seedlings of interior Douglas fir [Pseudotsuga menziesii var. glauca (Beissn.) France], Engelmann spruce [Picea engelmannii (Parry) Engelm.], and ponderosa pine (Pinus ponderosa var. scopulorum Engelm.) were acclimated and deacclimated to cold in growth chambers over 19 weeks. Heat tolerance and cold hardiness of needles, and bud dormancy, were measured weekly. Heat tolerance of Douglas fir and Engelmann spruce needles increased with development through the first complete annual cycle: new needles on actively growing plants; mature needles, not cold-hardy, on dormant plants; cold-hardy needles on dormant and quiescent plants; and mature, needles, not cold-hardy, on actively growing plants. Heat tolerance of ponderosa pine needles differed in two respects. New needles had an intermediate tolerance level to heat, and fully cold-hardy needles were the least tolerant. Thus, the physiological changes that conferred cold hardiness were not associated with greater heat tolerance in all the conifers tested. In none of these species did the timing of changes in heat tolerance coincide consistently with changes in cold hardiness or bud dormancy.

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Alfaro, Rene I. "LABORATORY FEEDING AND COLONIZATION OF NON-HOST LODGEPOLE PINE BY TWO POPULATIONS OF PISSODES STROBI (PECK) (COLEOPTERA: CURCULIONIDAE)." Canadian Entomologist 120, no. 2 (February 1988): 167–73. http://dx.doi.org/10.4039/ent120167-2.

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AbstractTwo populations of Pissodes strobi (Peck), one from Sitka spruce, Picea sitchensis (Bong.) Carr, and the other from Engelmann spruce, Picea engelmannii Parry ex Engelm., were successfully induced to oviposit on the non-host lodgepole pine, Pinus contorta Dougl. var latifolia. The number of egg punctures excavated on the non-host was smaller than that on either Sitka or Engelmann spruce. Survival from egg to adult was similar on the non-host and the host trees. The two weevil populations differed in the degree to which lodgepole pine met the nutritional requirements for weevil development, as measured by weight of weevils and developmental time from egg to adult. In choice-feeding experiments, weevils reared in lodgepole pine rejected this species and chose Sitka spruce, suggesting that feeding preference in P. strobi is genetically fixed and therefore cannot be changed by rearing the insects on the non-host tree. The importance of these findings is discussed in relation to the idea of weevil control through the development of weevil-resistant varieties.

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29

Lajzerowicz, C. C., A. Vyse, M. Jull, and T. Newsome. "Performance of planted Engelmann spruce and subalpine fir seedlings in British Columbia's southern mountains." Forestry Chronicle 82, no. 1 (January 1, 2006): 84–94. http://dx.doi.org/10.5558/tfc82084-1.

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We compared survival and growth of planted seedlings of Engelmann spruce and subalpine fir across a range of harvest opening sizes (> 10 ha, 1 ha, 0.2 ha, 0.1 ha, 0.03 ha and individual tree selection) from three silvicultural systems trials in high-elevation spruce – subalpine fir forests in south-central British Columbia. Climatic patterns and growing season air and soil temperatures were similar across sites. Seedling survival decreased with opening size. Local site climates, influenced by aspect and moisture and air drainage, were more influential than elevation. Seedling growth was best in large openings and similar in opening sizes from 1 ha to 0.1 ha. Smaller openings created by group selection and individual tree selection methods were not favourable for successful planting at elevations close to timberline. The two species had similar absolute and relative growth rates but spruce responded more strongly to better growing environments. Key words: planted seedlings, Engelmann spruce, Picea engelmannii Parry ex Engelm., subalpine fir, Abies lasiocarpa (Hook.) Nutt., opening size, elevation effects, silvicultural systems, British Columbia, mountain forests

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Gass, Tobah M., and Andrew P. Robinson. "A hierarchical analysis of stand structure, composition, and burn patterns as indicators of stand age in an Engelmann spruce – subalpine fir forest." Canadian Journal of Forest Research 37, no. 5 (May 2007): 884–94. http://dx.doi.org/10.1139/x06-301.

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We studied the relationship between observed fire effects and stand age in a recently burned subalpine Engelmann spruce ( Picea engelmannii Parry ex. Engelm.) – subalpine fir ( Abies lasiocarpa (Hook.) Nutt.) forest in New Mexico. We installed a network of variable-radius plots to assess stand structure, and cored 379 trees to measure the spatial patterns of the stand ages with respect to fire boundaries. We found that pre-fire stand age and stand mortality were not significantly related at either of two spatial scales (p ≤ 0.33 and p ≤ 0.26). We also found that stand structure and stand composition were poor indicators of stand age. The random effects terms of a linear mixed-effects model revealed substantial heterogeneity in stand structure and composition with respect to age at fine spatial scales. Discussions of the factors contributing to stand-replacing fires in subalpine Engelmann spruce – subalpine fir forests might be improved by focusing on traits that are more reliably linked to fuel characteristics, rather than on the age of the stands.

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Ernst, S. G., J. W. Hanover, and D. E. Keathley. "Assessment of natural interspecific hybridization of blue and Engelmann spruce in southwestern Colorado." Canadian Journal of Botany 68, no. 7 (July 1, 1990): 1489–96. http://dx.doi.org/10.1139/b90-189.

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In a partial diallel mating design among 20 blue and 20 Engelmann spruce parents, the interspecific crosses were successful only with Engelmann spruce as the female parent. No viable seed were obtained from the reciprocal cross among the 60 full-sib families attempted. Under the conditions of artificial pollination and a controlled germination environment, an average of 0.3% of the seed germinated on a total seed basis across all 20 Engelmann spruce females. Many abnormalities were observed among the germinating hybrid seed, suggesting hybrid inviability also contributes to the low crossability between these two species. Isozyme analysis was used to confirm the interspecific hybrids between blue and Engelmann spruce based on the unique genotypic compositions of the hybrids relative to the two species. No natural F1 hybrids between blue and Engelmann spruce were observed in this study based on isozyme analysis of mature individuals or their seedling progeny. Analyses included samples of open-pollinated seed from blue and Engelmann spruce females located in an area where both species are present in close proximity, often side-by-side, and where pollen shed and female strobilus receptivity in the two species are coincident. In addition, there was evidence of possible gametic selection or hybrid inviability among the full-sib progeny based on deviations of observed from expected segregation ratios for progeny isozyme genotypes. Deviations tended to favor the allele more common to both species rather than the allele unique or more common to only one species. Also, the elevationally allopatric blue and Engelmann spruce subpopulations were less divergent genetically than the sympatric subpopulations.

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Kinouchi, Renato Rodrigues. "Entrevista com Arno Engelmann." Scientiae Studia 7, no. 2 (June 2009): 325–30. http://dx.doi.org/10.1590/s1678-31662009000200011.

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33

Garcia Armario, María Dolores, and Carmen Vargas Lebron. "Síndrome de Camurati-Engelmann." Seminarios de la Fundación Española de Reumatología 12, no. 3 (July 2011): 91–97. http://dx.doi.org/10.1016/j.semreu.2011.06.002.

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34

de Bonilla Damiá, Álvaro, and Francisco Javier García Gómez. "Enfermedad de Camurati-Engelmann." Reumatología Clínica 13, no. 1 (January 2017): 48–49. http://dx.doi.org/10.1016/j.reuma.2015.12.004.

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35

Rajaratnam, HN. "Re: Camurati-Engelmann disease." Sri Lanka Journal of Diabetes Endocrinology and Metabolism 2, no. 2 (October 18, 2012): 121. http://dx.doi.org/10.4038/sjdem.v2i2.4785.

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36

Weickert, H., H. Lehr, and H. St Braun. "Diaphysäre Dysplasie (Camurati - Engelmann)." Zeitschrift für Orthopädie und ihre Grenzgebiete 121, no. 06 (March 18, 2008): 744–48. http://dx.doi.org/10.1055/s-2008-1053306.

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37

Tiberius, Richard G. "Artistʼs Statement: Engelmann Spruce." Academic Medicine 85, no. 1 (January 2010): 56. http://dx.doi.org/10.1097/acm.0b013e3181c87d65.

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38

Moreno-Giraldo, Lina Johanna, Stephany Ramírez-Ramírez, Daniela Arturo-Terranova, and José María Satizábal-Soto. "Enfermedad de Camurati-Engelmann." Revista Mexicana de Pediatría 87, no. 6 (2020): 221–26. http://dx.doi.org/10.35366/97684.

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39

Vyse, Alan, Christine Ferguson, and David J. Huggard. "Wind and snow damage nine years following four harvest treatments in a subalpine fir – Engelmann spruce forest at Sicamous Creek in southern interior British Columbia, Canada." Forestry Chronicle 84, no. 3 (June 1, 2008): 401–9. http://dx.doi.org/10.5558/tfc84401-3.

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We used transect surveys at a large-scale experimental site at Sicamous Creek, B.C. to measure the effects of five treatments on wind and snow damage in an old subalpine fir – Engelmann spruce forest: 10-ha clearcuts, arrays of 1-ha patch cuts, arrays of 0.1-ha patch cuts, individual-tree selection cuts and uncut controls. We also examined edge effects and conditions predisposing trees to damage. Transects were surveyed in 1997, 1999 and 2003 (2.7, 4.7 and 8.7 years postharvest). The increase in wind damage in the four harvested treatments compared to the uncut controls observed after 2.7 years was no longer evident following a snow damage event in the winter of 1998–1999, which was most severe in the uncut controls and leave strips. The damage recorded from this event was predominantly stem snapping rather than uprooting. Subsequent damage was low in all treatments, returning to the level first recorded in the uncut controls. Overall, after 8.7 years, the treatment differences were not statistically significant but the lowest average rates of damage were observed in the 0.1-ha patch cut arrays. The highest damage rates overall were observed within 10 m of the N and E edges of the 10-ha clearcuts. Damage rates in Engelmann spruce continued to be lower than rates for subalpine fir. Stem snapping, caused by some combination of snow loading and wind, is an underreported but widespread disturbance in these stands. Key words: ESSF forest, wind damage, snow damage, snapping, uprooting, subalpine fir (Abies lasiocarpa [Hook] Nutt.), Engelmann spruce (Picea engelmannii Parry ex Engelm.), silvicultural systems, Sicamous Creek

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Nault, J. R., J. F. Manville, and T. S. Sahota. "Spruce terpenes: expression and weevil resistance." Canadian Journal of Forest Research 29, no. 6 (June 1, 1999): 761–67. http://dx.doi.org/10.1139/x99-053.

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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.

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41

Engelmann, Arno. "A teoria das duas consciências: comentários." Paidéia (Ribeirão Preto) 12, no. 22 (2002): 107–9. http://dx.doi.org/10.1590/s0103-863x2002000100012.

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Lívia Simão citou a semelhança entre sua posição psicológica construtivista semiótico-cultural e as duas consciências de Engelmann. Nelson Coelho Jr. acha semelhança entre Husserl e Merleau-Ponty com o estudo da consciência de Engelmann. Entretanto, apesar do origem do conhecimento em si mesmo, Coelho Jr. aceita a realidade das outras pessoas e do mundo. Arno Engelmann respondeu aos raciocínios dos comentadores. Em resposta a Coelho Jr. declara que sua posição continua cética: a realidade das outras pessoas e do mundo é uma hipótese, ainda que uma hipótese de enorme probabilidade.

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42

Howe, Thomas E., Damithri T. Goonesekera, Nicolas J. Lee, and Sachin M. Salvi. "Correction of Orbital Deformity in Camurati-Engelmann Disease with PEEK Lateral Wall Implants." Craniomaxillofacial Trauma & Reconstruction Open 6 (January 1, 2021): 247275122110091. http://dx.doi.org/10.1177/24727512211009113.

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Camurati-Engelmann Disease is a rare congenital sclerosing bone dysplasia condition. Affected patients manifest bony abnormalities including thickening of the skull base and orbital bones. The resulting orbital volume reduction associated with this condition can cause exophthalmos, distorting the facial profile. The authors report a 33-year-old man with a diagnosis of Camurati-Engelmann Disease exhibiting exophthalmos who was successfully treated with the insertion of bilateral lateral orbital wall patient specific PEEK implants via a bi-coronal flap approach. This case highlights the novel application of modern cutting-edge technology in the treatment of proptosis in Camurati-Engelmann Disease.

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Coelho Junior, Nelson Ernesto. "Consciência, intencionalidade e intercorporeidade." Paidéia (Ribeirão Preto) 12, no. 22 (2002): 97–101. http://dx.doi.org/10.1590/s0103-863x2002000100010.

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Este texto tem por objetivo situar e discutir consciência, intencionalidade e intersubjetividade nas teorias fenomenológicas de Edmund Husserl e Maurice Merleau-Ponty, no contexto de um debate sobre a Teoria das Duas Consciências de Arno Engelmann. São propostas três questões ao professor Arno Engelmann.

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44

Conner, Lafe G., Michael C. Bunnell, and Richard A. Gill. "Forest diversity as a factor influencing Engelmann spruce resistance to beetle outbreaks." Canadian Journal of Forest Research 44, no. 11 (November 2014): 1369–75. http://dx.doi.org/10.1139/cjfr-2014-0236.

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Tree mortality because of beetle outbreaks has become substantial and widespread in conifer forests in western North America. A number of environmental and physiological factors influence patterns of mortality. Tree diversity may reduce the severity and extent of insect damage to host trees by providing associational resistance, but the existence and importance of associational resistance varies by forest type and by tree and insect species. We assessed whether plot-level tree diversity contributed to survival of Engelmann spruce (Picea engelmannii Parry ex Engelm.) following a spruce beetle (Dendroctonus rufipennis Kirby) epidemic. Our study plots comprised 2 to 5 tree species including Engelmann spruce, subalpine fir (Abies lasiocarpa (Hook) Nutt.), Douglas-fir (Pseudostuga menziesii (Mirb.) Franco), quaking aspen (Populus tremuloides Michx.), and white fir (Abies concolor (Gordon & Glend.) Hildebr.). We used a model-selection analysis to compare the importance of tree diversity with other known factors that influence spruce survival. We found lower rates of spruce survival in stands where spruce was the dominant tree species (by percent of stand density index) and higher survival in stands where nonspruce conifers (Douglas-fir, subalpine, and white fir) were dominant. We also found that tree diversity (Shannon index) did not show a positive correlation to spruce survival and that there was no additional benefit derived from the presence of aspen, which has higher phylogenetic distance from Engelmann spruce than the other trees in this study. The relationship between diversity and survival is complicated by factors that naturally co-vary with diversity, such as elevation, aspect, and stand density of spruce. Our results best support an explanation that if associational resistance does increase spruce survival during a beetle epidemic, it is due to host or resource dilution, which may be an indirect effect of higher stand diversity.

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Özşahin, Şükrü, Hilal Singer, Ali Temiz, and İbrahim Yıldırım. "Selection of softwood species for structural and non-structural timber construction by using the analytic hierarchy process (AHP) and the multi-objective optimization on the basis of ratio analysis (MOORA)." BALTIC FORESTRY 25, no. 2 (December 31, 2019): 281–88. http://dx.doi.org/10.46490/vol25iss2pp281.

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In this study, the hybrid approach of the analytic hierarchy process (AHP) and the multi-objective optimization on the basis of ratio analysis (MOORA) was used in order to select the most suitable softwood timber for constraction. Douglas fir (Pseudotsuga menziesii), Lodgepole pine (Pinus concorta), Red pine (Pinus resinosa), Redwood (Sequoia sempervirens), Engelmann spruce (Picea engelmannii), Eastern hemlock (Tsuga canadensis), Western larch (Larix occidentalis) and Western redcedar (Thuja plicata) were evaluated in terms of economic, physical, mechanical, thermal and durability properties. According to the results, the most suitable timbers for structural and non-structural applications were determined western larch and redwood, respectively.

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Youngblood, Andrew, and Dennis E. Ferguson. "Changes in needle morphology of shade-tolerant seedlings after partial overstory canopy removal." Canadian Journal of Forest Research 33, no. 7 (July 1, 2003): 1315–22. http://dx.doi.org/10.1139/x03-060.

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Recent studies with early-successional conifers have shown a correlation between changes in light regimes and changes in needle morphology. The objective of this study was to test the hypothesis that needles of late-successional conifers also respond to increased irradiance. We compared needle morphology of three co-occurring conifers, grand fir (Abies grandis (Dougl. ex D. Don) Lindl.), subalpine fir (Abies lasiocarpa (Hook.) Nutt.), and Engelmann spruce (Picea engelmannii Parry ex Engelm.). Morphological characteristics were examined for 4 years across three light environments: (1) open-canopy stands with 64% transmittance, (2) stands with 63% transmittance after a partial overstory removal treatment, and (3) closed-canopy stands with 29% transmittance. Needle width and length differed by year, but not by light environment. Mean stomatal density differed across years for all three species and increased with increasing irradiance for subalpine fir and Engelmann spruce. The number of mesophyll layers and the size of individual palisade mesophyll cells did not differ among the different light environments. The number of epidermis cell layers in each species was insensitive to changes in light environment and time. Our results indicate that these three conifers were unable to morphologically adapt their needles to an increase in light transmission caused by the partial removal of overstory canopies.

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Fettig, Christopher J., A. Steven Munson, Donald M. Grosman, and Darren C. Blackford. "Evaluations of Bole Injections for Protecting Engelmann Spruce from Mortality Attributed to Spruce Beetle (Coleoptera: Curculionidae) in the Intermountain West." Journal of Entomological Science 55, no. 3 (July 27, 2020): 301–9. http://dx.doi.org/10.18474/0749-8004-55.3.301.

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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.

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Anderson, R. Scott. "A 35,000 Year Vegetation and Climate History from Potato Lake, Mogollon Rim, Arizona." Quaternary Research 40, no. 3 (November 1993): 351–59. http://dx.doi.org/10.1006/qres.1993.1088.

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AbstractA new record from Potato Lake, central Arizona, details vegetation and climate changes since the mid-Wisconsin for the southern Colorado Plateau. Recovery of a longer record, discrimination of pine pollen to species groups, and identification of macrofossil remains extend Whiteside's (1965) original study. During the mid-Wisconsin (ca. 35,000-21,000 yr B.P.) a mixed forest of Engelmann spruce (Picea engelmannii) and other conifers grew at the site, suggesting a minimum elevational vegetation depression of ca. 460 m. Summer temperatures were as much as 5°C cooler than today. During the late Wisconsin (ca. 21,000-10,400 yr B.P.), even-cooler temperatures (7°C colder than today; ca. 800 m depression) allowed Engelmann spruce alone to predominate. Warming by ca. 10,400 yr B.P. led to the establishment of the modern ponderosa pine (Pinus ponderosa) forest. Thus, the mid-Wisconsin was not warm enough to support ponderosa pine forests in regions where the species predominates today. Climatic estimates presented here are consistent with other lines of evidence suggesting a cool and/or wet mid-Wisconsin, and a cold and/or wet late-Wisconsin climate for much of the Southwest. Potato Lake was almost completely dry during the mid-Holocene, but lake levels increased to near modern conditions by ca. 3000 yr B.P.

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Dannenmaier, B., and B. Weber. "Beobachtungen zum Camurati-Engelmann-Syndrom." RöFo - Fortschritte auf dem Gebiet der Röntgenstrahlen und der bildgebenden Verfahren 151, no. 08 (August 1989): 175–78. http://dx.doi.org/10.1055/s-2008-1047155.

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50

Jansma, Jerome, Harriet H. Jansma, and George Engelmann. "George Engelmann in Arkansas Territory." Arkansas Historical Quarterly 50, no. 3 (1991): 225. http://dx.doi.org/10.2307/40038186.

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Journal articles on the topic 'Engelmann'

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