How do biophysical factors contribute to height and basal area development in a mixed multiaged coast redwood stand?

ABSTRACT Wild pistachio (Pistacia atlantica Desf.) is an important tree species from dry forests of Eurasia. Seedlings must usually compete with other tree and shrub species in the dry harsh environment of mountain forests. In this study, we identified the main competitor species and evaluated some widely used competition indices, including distance-dependent and distance-independent ones, to quantify the relationship between the reference seedlings and their neighbors. The results indicated that the main competitors are mountain almond (Amygdalus scoparia Spach.), thorny almond (Amygdalus lycioides Spach.), montpellier maple (Acer monspessulanum subsp. cinerascens Boiss.) and other wild pistachio seedlings. We found that competition increases the height growth but reduces the diameter, basal area growth and crown development of wild pistachio seedlings. Some competition indices had a noticeable correlation with seedling growth, indicating that competition does exist. A combination of log-transformed indices could explain 85% of the diameter growth variations, 46% of height growth, 76% of basal area growth and 72% of crown area development with a good precision.

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Estimating site productivity in irregular stand structures by indexing the basal area or volume increment of the dominant species

Canadian Journal of Forest Research ◽

10.1139/cjfr-2013-0230 ◽

2014 ◽

Vol 44 (1) ◽

pp. 92-100 ◽

Cited By ~ 23

Author(s):

John-Pascal Berrill ◽

Kevin L. O’Hara

Keyword(s):

Basal Area ◽

Stand Density ◽

Site Productivity ◽

Mixed Stands ◽

Individual Tree ◽

Coast Redwood ◽

Stand Growth ◽

Permanent Sample Plots ◽

Partial Harvesting ◽

Volume Increment

Estimating site productivity in irregular structures is complicated by variations in stand density, structure, composition in mixed stands, and suppression experienced by subordinate trees. Our objective was to develop an alternate to site index (SI) and demonstrate its application in models of individual-tree and stand growth. We analyzed coast redwood (Sequoia sempervirens (Lamb. ex D. Don) Endl.) tree and stand growth in a grid of 234 permanent sample plots covering a 110 ha study area in north coastal California. Partial harvesting created a mosaic of densities and openings throughout the 60-year-old redwood-dominated forest. Redwood SI was a poor predictor of volume increment (VI) per hectare among redwood in each plot over two decades after harvest. A new index of redwood basal area increment (BAI) productivity, calculated using inventory data for all stems in even-aged stands and the oldest cohort of multiaged stands, was a stronger predictor of VI. Diameter increment of individual redwood trees correlated strongly with stand density and the new BAI index. Forest managers should expect widely divergent responses following partial harvesting in crowded even-aged stands, with the greatest response coming from dominant redwoods with long crowns retained in areas with low residual stand density and high BAI index.

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Predicting Potential Density and Basal Area Development in the Social Forestry Plantations ofAcacia niloticain Gujarat State of India

Journal of Sustainable Forestry ◽

10.1080/10549810701879750 ◽

2008 ◽

Vol 26 (4) ◽

pp. 284-300 ◽

Cited By ~ 1

Author(s):

Vindhya Prasad Tewari

Keyword(s):

Basal Area ◽

Social Forestry ◽

Potential Density ◽

Gujarat State ◽

The Social ◽

Forestry Plantations ◽

Area Development

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Simulating Multiaged Coast Redwood Stand Development: Interactions between Regeneration, Structure, and Productivity

Western Journal of Applied Forestry ◽

10.1093/wjaf/24.1.24 ◽

2009 ◽

Vol 24 (1) ◽

pp. 24-32 ◽

Cited By ~ 8

Author(s):

John-Pascal Berrill ◽

Kevin L. O'Hara

Keyword(s):

Stand Structure ◽

Basal Area ◽

Stand Density ◽

Site Index ◽

Growth And Yield ◽

Stand Development ◽

Area Index ◽

Coast Redwood ◽

Stand Growth ◽

Upper Limit

Abstract Multiaged management regimes and harvesting scenarios were simulated in coast redwood (Sequoia sempervirens [D. Don.] Endl.) stands using models of stand growth and yield (CRYPTOS) and stocking assessment (redwood MASAM). Various stocking and age-class combinations were modeled on site index 100 and 130 ft (50 years). Results demonstrated how the number of cohorts, upper limit of stocking, and cohort densities affected growth and yield. Board foot volume increment reached a plateau in stands with a prescribed upper limit of stocking above leaf area index 7.2 to 8.6. Productivity did not differ between stands with two to five cohorts producing the same tree size at harvest. It was affected by stand structure when a cutting cycle of 20 years was prescribed in stands with three to five cohorts. Stands with the same density returned to the upper limit of stocking much sooner on better sites. Prolonging the cutting cycle by reducing stand density resulted in larger tree sizes at harvest and greater productivity. The growth of trees remaining after cutting 10–50% of stand basal area and growth of new stump sprouts were also simulated. Stands quickly returned to preharvest stocking after light cutting, implying that heavy or frequent light cutting is needed to sustain growth and vigor of regeneration in multiaged coast redwood stands.

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Vertical structure and basal area development in second-growth Nothofagus stands in Chile

Journal of Applied Ecology ◽

10.1046/j.1365-2664.2003.00827.x ◽

2003 ◽

Vol 40 (4) ◽

pp. 639-645 ◽

Cited By ~ 22

Author(s):

Christopher H. Lusk ◽

Alicia Ortega

Keyword(s):

Vertical Structure ◽

Basal Area ◽

Second Growth ◽

Area Development

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Patterns of leaf area and growing space efficiency in young even-aged and multiaged coast redwood stands

Canadian Journal of Forest Research ◽

10.1139/x06-271 ◽

2007 ◽

Vol 37 (3) ◽

pp. 617-626 ◽

Cited By ~ 18

Author(s):

John-Pascal Berrill ◽

Kevin L. O’Hara

Keyword(s):

Leaf Area ◽

Basal Area ◽

Stem Volume ◽

Area Index ◽

Sapwood Area ◽

Coast Redwood ◽

Space Efficiency ◽

Second Growth ◽

Volume Increment ◽

Overstory Trees

Projected leaf area estimates were used to predict volume increment and basal area of second-growth coast redwood ( Sequoia sempervirens (D. Don) Endl.) trees on Jackson Demonstration State Forest, Mendocino County, California. Sample plots were established within even-aged and multiaged mixed-species stands. Redwood tree basal area growth was more strongly related to sapwood area than to tree size and differed significantly between canopy strata and overstory stratum crown classes. Projected leaf area was predicted from sapwood area for each tree, and summarized to the stand level, giving a maximum stand leaf area index (LAI) estimate of 14.9 m2/m2. Redwood tree growing space efficiency (GSE; the ratio of stem volume increment to leaf area) was greatest on average among emergent overstory trees, followed by dominant and codominant overstory trees. There was no evidence of declining overstory tree GSE with increasing leaf area over the range of data collected. A nonlinear model predicted increasing understory tree GSE with increasing leaf area. Models that predict basal area and LAI were developed to permit implementation of GSE models from basic inventory data.

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Multiaged redwood responds well to partial harvest and herbicide treatments

Canadian Journal of Forest Research ◽

10.1139/cjfr-2019-0142 ◽

2019 ◽

Vol 49 (11) ◽

pp. 1425-1433 ◽

Cited By ~ 3

Author(s):

John-Pascal Berrill ◽

Robert Howe

Keyword(s):

Rapid Growth ◽

Chemical Control ◽

Basal Area ◽

Efficient Tool ◽

Coast Redwood ◽

Partial Harvest ◽

Partial Harvesting ◽

Herbicide Treatments ◽

Cost Efficient ◽

Notholithocarpus Densiflorus

Chemical control of unwanted trees can be a cost-efficient tool for forest management and restoration. In California, United States, the response of merchantable conifers to hardwood control is poorly understood. We studied the tree growth of coast redwood (Sequoia sempervirens (Lamb. ex D. Don) Endl.) following herbicide frill treatment of competing tanoak (Notholithocarpus densiflorus (Hook. & Arn.) Manos, C.H. Cannon, & S. Oh), coinciding with a partial harvest of conifers. The radial growth of 420 redwoods in 45 plots was measured using increment cores. With or without partial harvesting, herbicide treatment of tanoak enhanced growth of most redwoods: 23% of redwoods in herbicide-only plots and 34% of redwoods in herbicide + harvest plots had ≥100% higher posttreatment basal area increment (BAI). In untreated plots, 67% of redwoods displayed declining BAI. The response of redwoods (the ratio of 8-year postharvest BAI to 8-year preharvest BAI) was 59% higher in herbicide-only plots and 108% higher in herbicide + harvest plots compared with untreated control plots over the same period. Redwoods with long crowns maintained rapid growth with or without treatment. Trees growing slowly before treatment exhibited the greatest response, provided that they had relatively long crowns and were not left in suppressed crown positions. Forest managers implementing partial harvesting and (or) chemical control of hardwoods can expect to maintain or promote rapid growth of most residual redwoods.

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