Ethylene and the Regulation of Growth in Pine

1973 ◽  
Vol 3 (1) ◽  
pp. 143-145 ◽  
Author(s):  
K. M. Brown ◽  
A. C. Leopold
Keyword(s):  
Radial Growth ◽  
Physical Stress ◽  
White Pine ◽  
Wind Action ◽  
Ethylene Content ◽  
Natural Stimulator ◽  
Regulation Of Growth

When branches of white pine are stressed by tying into loops, marked increases in the ethylene content of the internal atmosphere are noted. When an ethylene-generating paste is applied to localized regions, growth in diameter is increased there. It is suggested that ethylene may serve as a natural stimulator of radial growth associated with physical stress such as results from wind action.

The repeatability of stem exclusion during even-aged development of bigtooth aspen dominated forests

1993 ◽  
Vol 23 (6) ◽  
pp. 1156-1168 ◽  
Author(s):  
Brian J. Palik ◽  
Kurt S. Pregitzer
Keyword(s):  
Resource Availability ◽  
Radial Growth ◽  
Developmental Pattern ◽  
Forest Understory ◽  
White Pine ◽  
Development Patterns ◽  
Forest Development ◽  
Seed Availability ◽  
Initial Cohort ◽  
Landscape Level

Forest development following major disturbance is thought to follow a fairly repeatable temporal pattern. An initial cohort of trees establishes relatively rapidly (stand initiation), new establishment is precluded for an extended period (stem exclusion), and finally, new individuals again begin to establish, creating new age-classes in the forest understory (understory reinitiation), eventually leading to an uneven-aged condition. The current study was designed to assess the generality of this developmental pattern at the landscape level and gain insight into the possible mechanisms controlling stem exclusion and understory reinitiation in even-aged forests. Research was conducted within two bigtooth aspen (Populusgrandidentata Michx.) dominated landscapes in northern Lower Michigan having similar physical site characteristics, overstory compositions, and disturbance histories. The objectives for the study included (i) assessing the repeatability of development patterns within and between the two landscapes and (ii) exploring relationships between the timing of understory reinitiation and overstory growth characteristics and seed availability. Stem analysis was used to reconstruct establishment and growth histories of surviving stems in mature forest on replicate plots within each landscape. The age distributions of surviving individuals of all tree species in both forests reflected a developmental pattern characterized by rapid initial cohort establishment lasting 5–15 years, stem exclusion lasting 25–35 years, and understory reinitiation. The duration and timing of the developmental stages on the replicate plots were similar both within and between the two landscapes. There were, however, a small number of plots in landscape 2 that had substantially reduced stem exclusion lengths, relative to the remaining plots in both forests. Variation in the timing of understory reinitiation in landscape 2 was related to characteristics of remnant eastern white pine (Pinusstrobus L.) seed trees. The stem exclusion period was shorter, or almost nonexistent, on plots close to several large seed trees because of early, low-frequency establishment of white pine in the understory. Substantial increases in the frequency of understory establishment on all plots in landscape 2, as well as all new understory establishment on plots in landscape 1, were often associated with radial growth increases in overstory stems. The radial growth increases presumably reflected an increase in resource availability, possibly occurring in response to a concentrated wave of natural thinning within the bigtooth aspen dominated overstory. These results suggests that the timing of understory reinitiation may have been influenced by variation in seed availability interacting with changes in resource availability in the forest understory. A limited amount of new establishment occurred relatively early in forest development on plots that experienced abundant early seed rain, yet the bulk of new establishment occurred only after an increase in resource availability in the understory. The general patterns of forest development described in this study were similar both within and between landscapes. Similar descriptive studies are needed to address the repeatability of development patterns at the landscape level within other forest types. Additionally, experimental studies are needed to unequivocally identify the mechanisms controlling stem exclusion and understory reinitiation in even-aged forests.

scholarly journals Site and Stand Conditions Associated with Pine False Webworm Populations and Damage in Mature Eastern White Pine Plantations

2007 ◽  
Vol 24 (3) ◽  
pp. 168-176 ◽  
Author(s):  
Albert E. Mayfield ◽  
Douglas C. Allen ◽  
Russell D. Briggs
Keyword(s):  
New York ◽  
Radial Growth ◽  
New York State ◽  
Fine Sand ◽  
White Pine ◽  
Eastern White Pine ◽  
Growth Rings ◽  
Soil Carbon Content ◽  
Pine False Webworm ◽  
Stand Conditions

Abstract The influence of site and stand conditions on pine false webworm (Acantholyda erythrocephala [L.], Hymenoptera: Pamphiliidae) population densities and host damage was evaluated in 22 eastern white pine (Pinus strobus L.) stands in northern New York State. Mean pine false webworm density was positively related to stand size (ha) and inversely related to soil silt content (A-horizon) after holding stand size constant. Percent radial growth loss (during the first five years after defoliation began) was inversely related to soil carbon content (B-horizon) and inversely related to fine sand content (A-horizon) after holding B-horizon carbon constant. Severe radial growth suppression (missing or discontinuous growth rings) and white pine mortality were inversely related to live crown ratio. The frequency of trees with missing growth rings was inversely related to soil nitrogen (A-horizon) after holding live crown ratio constant. Stands located on sandy glacial lake shoreline/delta deposits had more coarsely textured soils with lower levels of organic matter and nitrogen and had slower height growth rates, lower tree diversity, greater relative dominance of white pine, and higher levels of pine false webworm defoliation than stands on adjacent landforms. These results may be useful to foresters managing eastern white pine stands in areas where similar site and stand conditions predominate and pine false webworm occurs.

THE NATURE OF THE ASSOCIATION OF EUROPHIUM TRINACRIFORME WITH POLE BLIGHT LESIONS

1957 ◽  
Vol 35 (6) ◽  
pp. 845-856 ◽  
Author(s):  
A. K. Parker
Keyword(s):  
British Columbia ◽  
Radial Growth ◽  
Growth Analysis ◽  
Radial Increment ◽  
White Pine ◽  
Histological Studies ◽  
Stem Section ◽  
Western White Pine ◽  
General Reduction

Europhium trinacriforme Parker was isolated from 11% of the lesions on western white pine affected with pole blight in the Interior of British Columbia and from 84% of the lesions on white pine on the Coast. This fungus was the only organism isolated more than twice from pole blight lesions and found to be pathogenic to white pine. However, it was unable to cause the pole blight condition within a period of 4 years after inoculation into healthy white pine. When this fungus was placed in wounds on white pine, lesions resulted which were similar to pole blight lesions in shape and in ability to cause resin exudation, but were otherwise dissimilar. On the basis of radial growth analysis it was evident that lesions occur following a general reduction in radial increment, and at the same time, or shortly after, the first crown symptoms of pole blight appear. Radial growth beneath lesions was nearly always less than in other parts of the stem section, indicating that both the position and extent of lesions are determined before they occur. Examinations of the number and size of lesions on pole blighted trees and the results of inoculations, isolations, and histological studies indicated that E. trinacriforme most likely gains entrance to lesions that are already formed from other causes and extends them.

Radial growth impact of pine false webworm defoliation on eastern white pine

2005 ◽  
Vol 35 (5) ◽  
pp. 1071-1086 ◽  
Author(s):  
Albert E Mayfield III ◽  
Douglas C Allen ◽  
Russell D Briggs
Keyword(s):  
Radial Growth ◽  
Time Lag ◽  
New York State ◽  
White Pine ◽  
Stem Analysis ◽  
Eastern White Pine ◽  
Increment Core ◽  
Annual Growth Rings ◽  
Pine False Webworm ◽  
The Impact

The impact of pine false webworm (Acantholyda erythrocephala (L.), Hymenoptera: Pamphiliidae) defoliation on the radial growth of mature eastern white pine (Pinus strobus L.) during an outbreak was assessed using a stem analysis comparison of two stands (defoliated vs. control) and increment cores collected from 21 defoliated stands and 5 control stands in northern New York State. Stem analysis revealed that whole-stem standardized annual volume increment (AVI) in a defoliated 67-year-old white pine stand (n = 10 sample trees) was reduced significantly below the AVI in the nondefoliated control stand (n = 8 sample trees) by the second year of moderate to heavy defoliation, and AVI was reduced by 97% by the fifth year of defoliation. No time lag between upper-bole and lower-bole impact was observed, and annual growth rings were more frequently missing or discontinuous at lower stem heights. The standardized latewood tracheid index was not reduced significantly below control stand levels until the third year of defoliation. Increment-core analysis revealed growth losses that corresponded with reported periods of defoliation in nearly all stands; sustained suppressions (5–16 continuous years) below a growth index of 0.5 occurred in over half of all defoliated stands. These results are discussed in relation to pine false webworm biology, comparisons with other conifer defoliators, environmental factors, and methods employed.

Impact of Pine Leaf Aphid, Pineus pinifoliae (Chermidae) on its Secondary Host, Eastern White Pine

1964 ◽  
Vol 96 (5) ◽  
pp. 765-772 ◽  
Author(s):  
Robert F. DeBoo ◽  
John B. Dimond ◽  
James H. Lowe
Keyword(s):  
Radial Growth ◽  
Stem Elongation ◽  
Radial Increment ◽  
Growth Reduction ◽  
Needle Length ◽  
White Pine ◽  
Normal Pattern ◽  
Aphid Infestation ◽  
Normal Branch ◽  
Lower Stem

AbstractPine leaf aphid infestation produces not only a general reduction in radial growth of white pine but also a modification of the normal pattern of annual radial increment along the length of the stem. The greatest growth reduction occurs in the lower stem with proportionately less in the midcrown area and least in the top. This appears to reflect the distribution of branch mortality which is greatest in the mid- and lower crown. Several defoliators studied by other workers produce the greatest effect on radial growth and on foliage survival in the tops of the tree.Stem elongation reduction occurs only after crown damage and aphid infestation becomes extreme. Lighter infestations are reflected, however, in reduced needle length in the year of attack followed by reduced branch elongation in the year following attack. The combination of stunted and normal needles alternating with stunted and normal branch internodes is probably a unique characteristic of pine leaf aphid damage.

Radial growth reductions of Pinusstrobus L. correlated with foliar ozone sensitivity as an indicator of ozone-induced losses in eastern forests

1982 ◽  
Vol 12 (3) ◽  
pp. 673-678 ◽  
Author(s):  
L. F. Benoit ◽  
J. M. Skelly ◽  
L. D. Moore ◽  
L. S. Dochinger
Keyword(s):  
Radial Growth ◽  
Radial Increment ◽  
Blue Ridge ◽  
White Pine ◽  
Shenandoah National Park ◽  
Blue Ridge Mountains ◽  
Ozone Sensitivity ◽  
Blue Ridge Parkway ◽  
Increment Growth

A study of the radial increment growth of native eastern white pine (Pinusstrobus L.) evaluated the possible effects of oxidant air pollution (primarily ozone) in long-term growth of forest species in the Blue Ridge Mountains of Virginia. Ten plots of three white pines of reproducing age (one each classified as tolerant, intermediate, and sensitive to ozone on a foliar basis) were sampled. Plots were dispersed over 446 km from the northern end of the Skyline Drive in Shenandoah National Park to the southern most part of the Blue Ridge Parkway in Virginia. Mean annual radial increment growth of the ozone sensitive trees was significantly smaller (P = 0.01) than that of tolerant trees for the period 1955–1978. Mean increment growth of all trees, regardless of their sensitivity to ozone, decreased during the period. Precipitation was positively correlated with radial growth in all sensitivity classes prior to 1964, but negatively correlated after 1964.

The influence of wind on ring width and cell length in conifer stems

1970 ◽  
Vol 48 (2) ◽  
pp. 255-259 ◽  
Author(s):  
M. W. Bannan ◽  
M. Bindra
Keyword(s):  
Radial Growth ◽  
Inverse Relationship ◽  
Ring Width ◽  
Cell Length ◽  
Prevailing Wind ◽  
The West ◽  
West Side ◽  
Wind Action ◽  
The Difference

In the three species studied, inequalities were noted in amount of radial growth around the stem. Rings tended to be wider on the east than on the west side. Because the prevailing wind is from the west, the eccentricity is interpreted as being due to wind action. In keeping with the general inverse relationship between ring width and cell length, the cells were longest on the west side where the rings were narrowest. The difference in cell length was not relatable to diversity in frequency of multiplicative divisions in the cambium.

Effects of Physical Training on Stuttering

1968 ◽  
Vol 11 (4) ◽  
pp. 767-776 ◽  
Author(s):  
B. Don Franks ◽  
Elizabeth B. Franks
Keyword(s):  
College Students ◽  
Group Therapy ◽  
Physical Training ◽  
Cardiovascular Response ◽  
Training Group ◽  
Physical Stress ◽  
Submaximal Exercise ◽  
Endurance Running ◽  
Response To Exercise

Eight college students enrolled in group therapy for stuttering were divided into two equal groups for 20 weeks. The training group supplemented therapy with endurance running and calisthenics three days per week. The subjects were tested prior to and at the conclusion of the training on a battery of stuttering tests and cardiovascular measures taken at rest, after stuttering, and after submaximal exercise. There were no significant differences (0.05 level) prior to training. At the conclusion of training, the training group was significandy better in cardiovascular response to exercise and stuttering. Although physical training did not significantly aid the reduction of stuttering as measured in this study, training did cause an increased ability to adapt physiologically to physical stress and to the stress of stuttering.

Health Profile White Pine County, Nevada 2001

2002 ◽  
Author(s):  
Lei Chen ◽  
Drew Mather ◽  
Sherry Torgerson
Keyword(s):  
Health Profile ◽  
White Pine
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