Long-term calcium addition increases growth release, wound closure, and health of sugar maple (Acer saccharum) trees at the Hubbard Brook Experimental Forest

2007 ◽  
Vol 37 (9) ◽  
pp. 1692-1700 ◽  
Author(s):  
Brett A. Huggett ◽  
Paul G. Schaberg ◽  
Gary J. Hawley ◽  
Christopher Eagar
Keyword(s):  
Acer Saccharum ◽  
Sugar Maple ◽  
Wound Closure ◽  
Hubbard Brook Experimental Forest ◽  
Hubbard Brook ◽  
Ca Addition ◽  
Significant Difference ◽  
Al Addition ◽  
And Control

We surveyed and wounded forest-grown sugar maple ( Acer saccharum Marsh.) trees in a long-term, replicated Ca manipulation study at the Hubbard Brook Experimental Forest in New Hampshire, USA. Plots received applications of Ca (to boost Ca availability above depleted ambient levels) or Al (to compete with Ca uptake and further reduce Ca availability). We found significantly greater total foliar and membrane-associated Ca in foliage of trees in plots fertilized with Ca when compared with trees from Al-addition and control plots (P = 0.005). Coinciding with foliar Ca differences, trees exhibited a significant difference in crown vigor and in percent branch dieback among treatments (P < 0.05), with a trend towards improved canopy health as Ca levels increased. Annual basal area increment growth for the years following treatment initiation (1998–2004) was significantly greater in trees subjected to Ca addition compared with trees in control and Al treatments. Treatment-related improvements in growth were particularly evident after overstory release following a 1998 ice storm. The amount of wound closure was also greatest for trees in Ca-addition plots relative to Al-addition and control plots (P = 0.041). These findings support evidence that ambient Ca depletion is an important limiting factor regarding sugar maple health and highlight the influence of Ca on wound closure and growth following release from competition.

Comment on “Long-term decline of sugar maple following forest harvest, Hubbard Brook Experimental Forest, New Hampshire”

2019 ◽  
Vol 49 (7) ◽  
pp. 861-862
Author(s):  
Scott W. Bailey ◽  
Robert P. Long ◽  
Stephen B. Horsley
Keyword(s):  
New England ◽  
Acer Saccharum ◽  
Sugar Maple ◽  
Management Practices ◽  
Hubbard Brook Experimental Forest ◽  
Data Set ◽  
Hubbard Brook ◽  
Whole Tree

Cleavitt et al. (2018, Can. J. For. Res. 48(1): 23–31, doi: 10.1139/cjfr-2017-0233 ) report a lack of sugar maple (Acer saccharum Marsh.) regeneration in Hubbard Brook Experimental Forest (HBEF), Watershed 5 (W5), following whole-tree clearcut harvesting and purport that harvesting-induced soil calcium depletion contributed to regeneration failure of this species. In New England, clearcutting is a silvicultural strategy used to promote less tolerant species, especially birch (Betula spp.; Marquis (1969), Birch Symposium Proceedings, USDA Forest Service; Leak et al. (2014), doi: 10.2737/NRS-GTR-132 ), which is just the outcome that the authors report. While this study reports an impressive, long-term data set, given broad interest in sugar maple and sustainability of forest management practices, we feel that it is critical to more fully explore the role of nutrition on sugar maple dynamics, both prior to and during the experiment, and to more fully review the scientific record on the role of whole-tree clearcutting in nutrient-induced sugar maple dynamics.

Reply to the comment by Bailey et al. on “Long-term decline of sugar maple following forest harvest, Hubbard Brook Experimental Forest, New Hampshire”

2019 ◽  
Vol 49 (7) ◽  
pp. 863-864
Author(s):  
John J. Battles ◽  
Natalie L. Cleavitt ◽  
Chris E. Johnson ◽  
Timothy J. Fahey
Keyword(s):  
Sugar Maple ◽  
Eastern North America ◽  
National Forest ◽  
Hubbard Brook Experimental Forest ◽  
Hubbard Brook ◽  
Soil Nutrition ◽  
Successful Recruitment ◽  
White Mountain National Forest ◽  
Forest Practice

Sugar maple decline in eastern North America is caused by a complex combination of factors, with soil nutrition being one of several important determinants. Given the complexity of sugar maple population dynamics and the geographic extent of the species, we support Bailey et al.’s (2019, Can. J. For. Res. 49(7), doi: 10.1139/cjfr-2018-0207 ) argument to interpret results from Cleavitt et al. (2018, Can. J. For. Res. 48(1): 23–31, doi: 10.1139/cjfr-2017-0233 ) with due caution. The experiment at Hubbard Brook Experimental Forest represents an atypical application of contemporary forest practice in the White Mountain National Forest; however, some comments in Bailey et al. (2019) missed the point; others inaccurately characterized our paper. Cleavitt et al.’s (2018) 30-year record of vegetation recovery following whole-tree harvest documented a worrisome inability of a sugar maple population that successfully established after harvest to maintain its position in the understory. This lack of persistence on base-poor soils such as those in the mid and upper elevations of Hubbard Brook Experimental Forest suggests that the successful recruitment of sugar maple is not guaranteed.

A randomized trial of levamisole versus placebo as adjuvant therapy in malignant melanoma.

1991 ◽  
Vol 9 (5) ◽  
pp. 736-740 ◽  
Author(s):  
L E Spitler
Keyword(s):  
Malignant Melanoma ◽  
Adjuvant Therapy ◽  
Randomized Trial ◽  
Control Groups ◽  
Disease Free Interval ◽  
Significant Difference ◽  
Long Term Follow Up ◽  
And Control

We conducted a long-term follow-up (median, 10.5 years) of patients included in a randomized trial of levamisole versus placebo as surgical adjuvant therapy in 203 patients with malignant melanoma. Of the patients randomized, 104 received levamisole, and 99 received placebo. The results show that there is no difference between the treatment and control groups with regard to any of the three end points analyzed. These included disease-free interval, time to appearance of visceral metastasis, and survival. Moreover, there was no significant difference between the treatment and control groups after adjusting for age, sex, or stage of disease.

scholarly journals What is the impact of methotrexate on liver in patients with juvenile idiopathic arthritis? Results of liver SWE performed in a single centre

2021 ◽  
Author(s):  
Vildan Güngörer ◽  
Mehmet Öztürk ◽  
Mustafa Yasir Özlü ◽  
Şükrü Arslan
Keyword(s):  
Juvenile Idiopathic Arthritis ◽  
Shear Wave Elastography ◽  
Term Therapy ◽  
Control Group ◽  
Significant Difference ◽  
Group 2 ◽  
Long Term Therapy ◽  
And Control ◽  
The Impact

ABSTRACT Objectives Long-term therapy with low-dose methotrexate (MTX) is widely used in treatment of rheumatic diseases, in children. The purpose of this study was to evaluate liver elasticity in patients with juvenile idiopathic arthritis (JIA) who received MTX and compare the results with control group. Methods Liver elasticity was evaluated with shear wave elastography (SWE) technique in 25 patients aged 3–17 years who were followed up with JIA and received MTX and compared with 25 healthy controls of the same age and weight. Factors that had an effect on liver elasticity were examined. Results The mean SWE value of patients was 2.64 ± 2.13 m/s and 24.10 ± 18.50 kPa, whereas 1.83 ± 0.16 m/s and 10.09 ± 1.83 kPa in control group. There was a significant difference in liver elasticity in the patient and control groups. When the patients were evaluated as Group 1 (&lt; 1000 mg) and Group 2 (≥ 1000 mg) according to the cumulative MTX dose, no significant difference was obtained. There was positive correlation between liver elasticity and weekly MTX dose and age. Conclusions Our study revealed that liver elasticity significantly decreased in patients who received MTX when compared with the control group. The elastography technique will be understood better over time and used safely in many areas.

scholarly journals Long-term trends from ecosystem research at the Hubbard Brook Experimental Forest

2007 ◽  
Author(s):  
John L. Campbell ◽  
Charles T. Driscoll ◽  
Christopher Eagar ◽  
Gene E. Likens ◽  
Thomas G. Siccama ◽  
...  
Keyword(s):  
Hubbard Brook Experimental Forest ◽  
Ecosystem Research ◽  
Hubbard Brook ◽  
Long Term Trends

Long-term impact of liming on growth and vigor of northern hardwoods

2011 ◽  
Vol 41 (6) ◽  
pp. 1295-1307 ◽  
Author(s):  
Robert P. Long ◽  
Stephen B. Horsley ◽  
Thomas J. Hall
Keyword(s):  
Acer Saccharum ◽  
Sugar Maple ◽  
Keystone Species ◽  
Basal Area ◽  
Fagus Grandifolia ◽  
Northern Hardwood ◽  
Crown Health ◽  
Lime Application ◽  
Species Specific

Sugar maple (Acer saccharum Marsh.) is a keystone species in the northern hardwood forest, and decline episodes have negatively affected the growth and health of sugar maple in portions of its range over the past 50+ years. Crown health, growth, survival, and flower and seed production of sugar maple were negatively affected by a widespread decline event in the mid-1980s on the unglaciated Allegheny Plateau in northern Pennsylvania. A long-term liming study was initiated in 1985 to evaluate responses to a one-time application of 22.4 Mg·ha–1 of dolomitic limestone in four northern hardwood stands. Over the 23-year period ending in 2008, sugar maple basal area increment (BAINC) increased significantly (P ≤ 0.05) in limed plots from 1995 through 2008, whereas American beech (Fagus grandifolia Ehrh.) BAINC was unaffected. For black cherry (Prunus serotina Ehrh.), the third principal overstory species, BAINC and survival were reduced in limed plots compared with unlimed plots. Foliar Ca and Mg remained significantly higher in sugar maple foliage sampled 21 years after lime application, showing persistence of the lime effect. These results show long-term species-specific responses to lime application.

Leaf- and plant-level carbon gain in yellow birch, sugar maple, and beech seedlings from contrasting forest light environments

2000 ◽  
Vol 30 (3) ◽  
pp. 390-404 ◽  
Author(s):  
Marilou Beaudet ◽  
Christian Messier ◽  
David W Hilbert ◽  
Ernest Lo ◽  
Zhang M Wang ◽  
...  
Keyword(s):  
Acer Saccharum ◽  
Sugar Maple ◽  
Light Availability ◽  
Fagus Grandifolia ◽  
Carbon Gain ◽  
Betula Alleghaniensis ◽  
Yellow Birch ◽  
Significant Difference ◽  
Leaf Level ◽  
Plant Level

Leaf-level photosynthetic-light response and plant-level daily carbon gain were estimated for seedlings of moderately shade-tolerant yellow birch (Betula alleghaniensis Britton) and shade-tolerant sugar maple (Acer saccharum Marsh.) and beech (Fagus grandifolia Ehrh.) growing in gaps and under a closed canopy in a sugar maple stand at Duchesnay, Que. All three species had a higher photosynthetic capacity (Amax) in the gaps than in shade, but yellow birch and beech responded more markedly than sugar maple to the increase in light availability. The high degree of plasticity observed in beech suggests that the prediction that photosynthetic plasticity should decrease with increasing shade tolerance may not hold when comparisons are made among a few late-successional species. Unit-area daily carbon gain (CA) was significantly higher in the gaps than in shade for all three species, but no significant difference was observed between light environments for plant-level carbon gain (CW). In shade, we found no difference of CA and CW among species. In gaps, beech had a significantly higher CA than sugar maple but similar to that of birch, and birch had a significantly higher CW than maple but similar to that of beech. Sugar maple consistently had lower carbon gains than yellow birch and beech but is nevertheless the dominant species at our study site. These results indicate that although plant-level carbon gain is presumably more closely related to growth and survival of a species than leaf-level photosynthesis, it is still many steps removed from the ecological success of a species.

Elevation dependent sensitivity of northern hardwoods to Ca addition at Hubbard Brook Experimental Forest, NH, USA

2010 ◽  
Vol 260 (12) ◽  
pp. 2115-2124 ◽  
Author(s):  
Rakesh Minocha ◽  
Stephanie Long ◽  
Palaniswamy Thangavel ◽  
Subhash C. Minocha ◽  
Christopher Eagar ◽  
...  
Keyword(s):  
Northern Hardwoods ◽  
Hubbard Brook Experimental Forest ◽  
Hubbard Brook ◽  
Ca Addition

Discolouration and decay associated with paraformaldehyde-treated tapholes in sugar maple

1978 ◽  
Vol 8 (1) ◽  
pp. 54-60 ◽  
Author(s):  
Russell S. Walters ◽  
Alex L. Shigo
Keyword(s):  
New York ◽  
Sugar Maple ◽  
Rapid Development ◽  
Mature Trees ◽  
Total Length ◽  
Sugar Maples ◽  
Significant Difference ◽  
Final Measurement ◽  
Repeated Use ◽  
And Control

More decay (higher incidence and greater total length of column) was associated with tapholes in mature sugar maples (Acersaccharum Marsh.) treated with a 250-mg paraformaldehyde pill than with control tapholes. This was apparent 20 months after treatment and at each successive examination to the final measurement at 56 months. Discoloured columns associated with pill-treated tapholes were longer than those associated with control tapholes for the first 8 months. From that time until the final measurement there were no statistically significant differences between lengths of discoloured columns associated with pill-treated and control tapholes. Cambial dieback occurred adjacent to many tapholes but there was no significant difference in closure rates of treated and control tapholes. Results were obtained from dissections and studies of 180 mature trees over a 56-month period in six locations in Vermont in one experiment, and from 75 trees over a 20-month period in three locations each in Vermont, Maine, New York, Pennsylvania, and Michigan in another experiment. The results indicate that repeated use of paraformaldehyde will lead to rapid development of decay in sugar maple trees.

scholarly journals Influence of long term stress exposure on somatisation symptoms outcome

2004 ◽  
Vol 4 (4) ◽  
pp. 28-31
Author(s):  
Sabaheta Hasić ◽  
Emina Kiseljaković ◽  
Radivoj Jadrić ◽  
Belma Zečević ◽  
Nešina Avdagić ◽  
...  
Keyword(s):  
Chronic Stress ◽  
Control Group ◽  
Stress Exposure ◽  
War Stress ◽  
Control Subjects ◽  
Study Results ◽  
Significant Difference ◽  
Student’S T ◽  
And Control

Long term stress exposure results in somatisation symptoms appearance. Cardiovascular, respiratory, gastrointestinal and muscle-bone symptoms arise because of intensified activity of autonomic nervous system caused by chronic stress. The aim of the study was to examine the relationship between long term war stress exposure and appearance of somatisation. 40 students of health-care faculties in Sarajevo, of both sexes, were included in investigation and divided in two groups-somatisation and control. Somatisation group subjects (N=20) lived in B&H under war conditions, from 1992-1995. Control subjects (N=20) spent the same period outside B&H. For evaluation of somatisation symptoms we used SCL-90-R test. The obtained data were statistically evaluated using Student’s t-test and χ2 test. Confidence level was set at ρ < 0,05. Our results showed statistically significant difference in somatisation level between somatisation and control subjects group. Different intensity of appearance of certain symptoms in male and female was established. The score of somatisation dimension between somatisation and control group showed statistically significant level (p < 0,0001). Study results confirmed correlation of chronic stress exposure (living in war environment) and somatisation symptom appearance. Individual organic systems had various level of symptom expression. The influence of sex on intensity of individual symptoms of somatisation is possible.

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