Sitka alder, a candidate for mixed stands

1982 ◽  
Vol 12 (1) ◽  
pp. 108-111 ◽  
Author(s):  
Constance A. Harrington ◽  
Robert L. Deal
Keyword(s):  
Organic Matter ◽  
Head Start ◽  
Growth Curves ◽  
Poor Quality ◽  
Height Growth ◽  
Douglas Fir ◽  
Nitrogen Fixing ◽  
Mixed Stands

Juvenile height growth of Sitka alder (Alnussinuata (Regel) Rydb.), a nitrogen-fixing shrub, was examined on eight sites. The potential compatibility of mixed stands of Sitka alder and Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) was then assessed by comparing height-growth curves of the two species at early ages. Based on Sitka alder's low height and early slowdown in height growth, it appears to be a reasonable candidate for mixed stands on sites where additions of nitrogen or organic matter are desirable. On poor quality Douglas-fir sites, however, Douglas-fir should be given a head start to insure that it is not suppressed.

HEIGHT GROWTH LOSSES DUE TO ANIMAL FEEDING IN DOUGLAS FIR PLANTATIONS, VANCOUVER ISLAND, B.C.

1964 ◽  
Vol 40 (3) ◽  
pp. 298-307 ◽  
Author(s):  
K. J. Mitchell
Keyword(s):  
Pseudotsuga Menziesii ◽  
East Coast ◽  
Growth Curves ◽  
Tree Height ◽  
Vancouver Island ◽  
Height Growth ◽  
Douglas Fir ◽  
Average Height ◽  
Animal Feeding ◽  
Rotation Age

Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) plantations on the east coast of Vancouver Island, British Columbia, were examined to determine the effect of animal feeding upon height growth.Length of internodes and evidence of past leader damage were recorded and cumulative average height-age growth curves compared for undamaged trees and for trees suffering various intensities of damage.The average reduction in tree height attributable to animal feeding in heavily browsed plantations varied from one-half to two feet over a period of 8 to 10 years. It is unlikely that either tree volume or quality at rotation age would be seriously affected.Exposed trees were browsed more heavily than those protected by vegetation or logging slash.

Size of Douglas-fir trees in relation to distance from a mixed red alder–Douglas-fir stand

1993 ◽  
Vol 23 (11) ◽  
pp. 2413-2418 ◽  
Author(s):  
Richard E. Miller ◽  
Donald L. Reukema ◽  
Timothy A. Max
Keyword(s):  
Stand Density ◽  
Positive Influence ◽  
Poor Quality ◽  
Douglas Fir ◽  
Mixed Stand ◽  
Stem Volume ◽  
Nitrogen Fixing ◽  
Red Alder ◽  
Wide Strip ◽  
Southwest Washington

Variation in diameter, height, and stem volume of 57-year-old Douglas-fir (Pseudotsugamenziesii var. menziesii (Mirb.) Franco) was related to distance of these trees from a 27 m wide strip in the same Douglas-fir plantation that had been interplanted with red alder (Alnusrubra Bong.). Within the interplanted strip and despite its greater total stand density, bole volume of dominant and codominant Douglas-fir averaged 1.27 m3 compared with 0.55, 0.45, 0.46, or 0.49 m3 in trees 15, 30,45, or 60 m, respectively, from the edge of the mixed stand. Some positive influence of nitrogen-fixing red alder apparently extended about 15 m beyond the edge of the mixed stand at this poor quality site in southwest Washington. We infer that similar ribbonlike distributions of naturally regenerated red alder could be retained to improve growth of nearby conifers on nitrogen-deficient sites.

Nitrogen Fixation: A Biotechnological Opportunity for Canadian Forestry

1983 ◽  
Vol 59 (5) ◽  
pp. 249-259 ◽  
Author(s):  
L. Chatarpaul ◽  
A. Carlisle
Keyword(s):  
Organic Matter ◽  
Nitrogen Fixation ◽  
Genetic Selection ◽  
Field Trials ◽  
Management Systems ◽  
Nitrogen Fixing ◽  
Site Productivity ◽  
Mixed Stands ◽  
Trees And Shrubs ◽  
Selection Of

Intensive harvesting and forest management systems will increase nitrogen and organic matter losses from forest soils, and there will be a need to manage the soils using both fertilizers and nitrogen-fixing techniques to maintain site productivity. Legumes and non-legumes with nitrogen-fixing symbioses can fix up to 300 kg ha−1 year−1 of nitrogen and provide soil organic matter, but poor soils will need fertilization to maintain the nitrogen-fixing process. There are many species and cultural techniques the forester can use, including green manuring and mixed stands, but carefully designed field trials are needed to solve cultural problems. In addition, there are many opportunities for genetic selection of both the trees and shrubs and the bacteria (actinomycetes) involved. Before the systems can be used effectively the operational foresters will need to be better informed about the soil biota and the interaction with site and vegetation. The development of nitrogen-fixing systems offers a biotechnological opportunity for Canadian foresters to increase tree yield while maintaining site productivity.

Site Index and Height Growth Curves for Ponderosa Pine, Western Larch, Lodgepole Pine, and Douglas-Fir in Western Montana

1992 ◽  
Vol 7 (1) ◽  
pp. 9-14 ◽  
Author(s):  
Kelsey S. Milner
Keyword(s):  
Ponderosa Pine ◽  
Growth Curves ◽  
Analysis Data ◽  
Site Index ◽  
Height Growth ◽  
Douglas Fir ◽  
Growth Patterns ◽  
Western Montana ◽  
Stem Analysis ◽  
Western Larch

Abstract Height growth patterns from several published site curve sytems for ponderosa pine (Pinus ponderosa), Douglas-fir (Pseudotsuga menziesii var glauca), western larch (Larix occidentalis) and lodgepole pine (Pinus contorta var latifolia) were compared to stem analysis data from western Montana. Most of the published curves had height growth patterns that differed significantly from those in the data. The magnitude of the deviations often varied by level of site index; this appeared to be related to differences in the range of site qualities sampled. Those curves constructed from stem analysis data from geographically similar populations compared most closely. Curves constructed using guide curve techniques showed a consistent tendency to underpredict heights at greater ages. New site index and height growth curves are presented for each species. West. J. Appl. For. 7(1):9-14.

Comparison of Douglas-fir site index and height growth curves in the Pacific Northwest

1985 ◽  
Vol 15 (4) ◽  
pp. 673-679 ◽  
Author(s):  
Robert A. Monserud
Keyword(s):  
Pacific Northwest ◽  
Growth Curves ◽  
Site Index ◽  
Height Growth ◽  
Douglas Fir ◽  
Stem Analysis ◽  
The Pacific ◽  
Northern Rockies ◽  
Growth Differences ◽  
Index Curve

Site index and height growth curves produced by the major Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) site index studies in the Pacific Northwest are graphically compared. Results indicate that differences in the height growth pattern of Douglas-fir increase with increasing distance between regions. Height growth differences were extremely small between the northern Rockies and the east side of the Cascades and were rather large between the Rockies and the west side of the Cascades. The relatively small differences between the northern Rockies and the Cascade crest fell between these two extremes. Very small differences were also found between Montana and northern Idaho. A second result of the comparisons is that the type of data and the resulting methodology used to develop the site index curve system are strongly related to the similarity of the resulting curves. Curves derived from felled-tree, stem-analysis studies were quite similar to each other, but differed substantially from curves derived by harmonized guide-curve methods. Furthermore, the guide-curve systems produced curves that were surprisingly similar to each other, even though different varieties of Douglas-fir from different regions were being compared. The magnitude of the differences that could be attributed solely to different methods of site curve construction (stem analysis vs. guide curve) was demonstrated to be quite large by applying both methods to the same data. The often untenable assumptions inherent in guide-curve systems appear to affect the shape of the curves more than real regional height growth differences.

scholarly journals Growth in achondroplasia, from birth to adulthood, analysed by the JPA-2 model

2020 ◽  
Vol 33 (12) ◽  
pp. 1589-1595
Author(s):  
Mariana del Pino ◽  
Virginia Fano ◽  
Paula Adamo
Keyword(s):  
General Population ◽  
Growth Curve ◽  
Growth Velocity ◽  
Adult Height ◽  
Growth Curves ◽  
Peak Height ◽  
Height Growth ◽  
Individual Growth ◽  
Height Velocity ◽  
Peak Height Velocity

AbstractObjectivesIn general population, there are three phases in the human growth curve: infancy, childhood and puberty, with different main factors involved in their regulation and mathematical models to fit them. Achondroplasia children experience a fast decreasing growth during infancy and an “adolescent growth spurt”; however, there are no longitudinal studies that cover the analysis of the whole post-natal growth. Here we analyse the whole growth curve from infancy to adulthood applying the JPA-2 mathematical model.MethodsTwenty-seven patients, 17 girls and 10 boys with achondroplasia, who reached adult size, were included. Height growth data was collected from birth until adulthood. Individual growth curves were estimated by fitting the JPA-2 model to each individual’s height for age data.ResultsHeight growth velocity curves show that after a period of fast decreasing growth velocity since birth, with a mean of 9.7 cm/year at 1 year old, the growth velocity is stable in late preschool years, with a mean of 4.2 cm/year. In boys, age and peak height velocity in puberty were 13.75 years and 5.08 cm/year and reach a mean adult height of 130.52 cm. In girls, the age and peak height velocity in puberty were 11.1 years and 4.32 cm/year and reach a mean adult height of 119.2 cm.ConclusionsThe study of individual growth curves in achondroplasia children by the JPA-2 model shows the three periods, infancy, childhood and puberty, with a similar shape but lesser in magnitude than general population.

Partial cut harvesting and ectomycorrhizae: early effects in Douglas-fir-larch forests of western Montana

1980 ◽  
Vol 10 (3) ◽  
pp. 436-440 ◽  
Author(s):  
A. E. Harvey ◽  
M. J. Larsen ◽  
M. F. Jurgensen
Keyword(s):  
Organic Matter ◽  
Soil Organic Matter ◽  
Douglas Fir ◽  
The Other ◽  
Western Montana ◽  
Root Tips ◽  
Residue Removal ◽  
Larch Forests ◽  
Early Effects

Numbers of ectomycorrhizae were assessed 3 years after harvesting approximately 50% of the overstory in two Douglas-fir-larch stands in western Montana, one was subjected to intensive residue removal, the other broadcast burned 1 year after harvest. Numbers of active ectomycorrhizal root tips were significantly reduced in the broadcast burned stand compared to either the intensively utilized stand or to an adjacent, undisturbed stand. This indicates that on difficult-to-regenerate sites, particularly where soil organic matter is low, it may be advantageous to dispose of slash created in partial cuts by means other than burning.

Nitrogen-fixing bacteria in Douglas-fir residue decayed byFomitopsis pinicola

1982 ◽  
Vol 68 (1) ◽  
pp. 117-123 ◽  
Author(s):  
S. D. Spano ◽  
M. F. Jurgensen ◽  
M. J. Larsen ◽  
A. E. Harvey
Keyword(s):  
Douglas Fir ◽  
Nitrogen Fixing ◽  
Nitrogen Fixing Bacteria

scholarly journals Soil texture and other site-level factors differentially affect growth of Scotch broom (Cytisus scoparius) and Douglas-fir (Pseudotsuga menziesii) seedlings in the western Pacific Northwest

2021 ◽  
Author(s):  
David Carter ◽  
Robert A. Slesak ◽  
Timothy B. Harrington ◽  
Anthony W. D’Amato
Keyword(s):  
Pacific Northwest ◽  
Pseudotsuga Menziesii ◽  
Height Growth ◽  
Douglas Fir ◽  
Western Pacific ◽  
Limiting Factor ◽  
Cytisus Scoparius ◽  
Invasive Shrub ◽  
Scotch Broom ◽  
The Western Pacific

The invasive shrub Scotch broom (Cytisus scoparius (L.) Link) is a pervasive threat to regenerating Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco var. menziesii) stands in the Pacific Northwest, USA. Field observations indicate that the susceptibility of areas to Scotch broom invasion and dominance can vary by site. We selected ten sites throughout the western Pacific Northwest that spanned a gradient of soil textures and other factors to test the site-specific susceptibility of Douglas-fir to overtopping by Scotch broom. We expected to find that the ability of Scotch broom to dominate a site was mediated by site-level factors, particularly those influencing soil water – the most limiting factor to growth in the region. We found Scotch broom and Douglas-fir were inversely affected by site-level factors. In general, Douglas-fir absolute height growth rates were more competitive with those of Scotch broom on fine-textured soils than on more coarsely textured soils. We also found Douglas-fir to have a more dramatic response to increasing down woody material than Scotch broom. Scotch broom height growth approached an asymptote at 3 m. Sites with fast-growing Douglas-fir were able to surpass this height six to seven years after planting and appear likely to avoid suppression by Scotch broom.

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