Effects of Tree Shelters on the Survival and Growth ofArgania spinosaSeedlings in Mediterranean Arid Environment

The argan tree is endemic species of Morocco. It occupies an area of more than 8700 km2and plays essential ecological and economical roles. In spite of their value, the argan woodlands are subject to rapid and uncontrolled degradation during the last decades, mainly due to overgrazing and systematic collection of argan nuts. The present study was carried out to investigate the effects of two types of tree shelters on survival and growth ofArgania spinosaseedlings planted in the southwest of Morocco in order to improve the results of reforestation programs which usually end by repeated failures. The experiment was conducted in the Mesguina forest for two growing seasons after transplantation in the field. After two years, the use of tree shelters significantly increased tree survival and allowed a gain of 20%. Height growth was positively affected by tree shelters. The use of tree shelters showed no significant decrease in basal diameter. In contrast, the height to diameter ratios of sheltered trees were much higher compared to the control. Thus, the use of the tree shelters could aid the early establishment and growth ofArgania spinosaunder conditions similar to those of the experiment.

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Early Landscape Performance of 20 Field-Grown Birch Genotypes at Two Locations in Arkansas, U.S. and Response to Irrigation

Arboriculture & Urban Forestry ◽

10.48044/jauf.2007.031 ◽

2007 ◽

Vol 33 (4) ◽

pp. 275-282

Author(s):

Mengmeng Gu ◽

James Robbins ◽

Curt Rom

Keyword(s):

Betula Pendula ◽

Tree Height ◽

The Other ◽

Annual Change ◽

Trunk Diameter ◽

Growing Seasons ◽

Landscape Performance ◽

Tree Survival ◽

Birch Trees ◽

Survival And Growth

Twenty birch genotypes were planted in the field in April 2002 to evaluate their survival and growth at Fayetteville and Hope, Arkansas, U.S., and to evaluate their response to two irrigation regimes at Fayetteville. After four growing seasons, the overall tree survival was 62% and 30% at Fayetteville and Hope, respectively. Betula pendula ‘Trost’s Dwarf’, B. ermanii, and B. albosinensis were among genotypes with the lowest survival at both locations. Betula populifolia, B. nigra ‘BNMTF’, B. nigra ‘Cully’, and B. × ‘Royal Frost’ had greater survival after four growing seasons than the other birch genotypes investigated. Betula nigra ‘BNMTF’ and B. nigra ‘Cully’ were taller and had greater trunk diameter than the other surviving birch genotypes at both locations after four growing seasons. At the end of 2005, B. utilis var. jacquemontii was the shortest and had the smallest trunk diameter among the 18 surviving genotypes at Fayetteville, and B. papyrifera ‘Uenci’, B. populifolia ‘Whitespire’, B. maximowicziana, and B. lenta were the shortest and had the smallest trunk diameter among the 13 surviving genotypes at Hope. At Fayetteville, B. nigra and B. davurica had the greatest annual change in tree height in both 2004 and 2005, and B. davurica was among genotypes having the greatest annual change in trunk diameter in 2002, 2004, and 2005. At Hope, B. papyrifera had the greatest annual change in tree height in both 2004 and 2005, and B. davurica had the greatest annual change in trunk diameter in 2004. In 2005, annual change was not significant among birch genotypes at Hope. At Fayetteville, water-stress treatment reduced final tree height and trunk diameter in birch trees.

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Tree Shelters Improve the Survival and Growth of Planted Engelmann Spruce Seedlings in Southwestern Colorado

Western Journal of Applied Forestry ◽

10.1093/wjaf/16.3.114 ◽

2001 ◽

Vol 16 (3) ◽

pp. 114-120 ◽

Cited By ~ 5

Author(s):

Douglass F. Jacobs ◽

Klaus Steinbeck

Keyword(s):

Rocky Mountains ◽

Growing Season ◽

High Elevation ◽

Picea Engelmannii ◽

Control Treatment ◽

Growth And Survival ◽

Tree Shelters ◽

Engelmann Spruce ◽

Growing Seasons ◽

Survival And Growth

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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Triterpenoids from Argania spinosa: 20 Years of Research

Natural Product Communications ◽

10.1177/1934578x1300800110 ◽

2013 ◽

Vol 8 (1) ◽

pp. 1934578X1300800 ◽

Cited By ~ 2

Author(s):

Imane Chafchaouni-Moussaoui ◽

Zoubida Charrouf ◽

Dom Guillaume

Keyword(s):

Research Evidence ◽

Economic Potential ◽

Lead Compound ◽

Argania Spinosa ◽

Argan Oil ◽

Argan Tree ◽

Phytochemical Investigation ◽

The World ◽

The Subject

During the last two decades, the argan tree has been the subject of intensive phytochemical investigation. If argan oil is the most known argan derivative, argan saponins are frequently considered as molecules presenting a strong economic potential. This review presents an update of the current research efforts on argan saponins from around the world. Research evidence suggests that arganine C can be considered as a lead compound for new antivirals.

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Integrated vegetation management in California – advances and future

The Forestry Chronicle ◽

10.5558/tfc67528-5 ◽

1991 ◽

Vol 67 (5) ◽

pp. 528-531 ◽

Cited By ~ 1

Author(s):

Gary O. Fiddler ◽

Philip M. McDonald

Keyword(s):

Good Control ◽

Vegetation Management ◽

Bureau Of Land Management ◽

Private Industry ◽

Conifer Seedlings ◽

Central California ◽

Competing Vegetation ◽

Growing Seasons ◽

Survival And Growth ◽

Mechanical Release

A study on alternatives for releasing young conifer plantations on National Forests in northern and central California was started in 1980, and enlarged to include State of California, Bureau of Land Management, and private industry lands. Forty studies involving chemical, manual, mechanical, mulch, and animal treatments have been established and their effect on the survival and growth of conifer seedlings is being quantified. Plant diversity and succession on both treated and untreated sites are being recorded. The oldest study has had 10 growing seasons since the first treatments were applied. To release conifer seedlings, a treatment radius of at least 1.5 meters is required; smaller radii do not provide enough site resources for acceptable growth. Diameter, rather than height, is the best indicator of release. Some non-phenoxy chemicals show promise for good control of competing vegetation. Mechanical release requires additional treatments to effectively control shrubs. Mulching has given limited results to date. Manual treatments, if applied to non-sprouting and nonrhizomatous plants soon after planting, and usually more than once, provide adequate control of competing vegetation, but are costly.

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Genetic diversity and population structure of the endangered argan tree (Argania spinosa L. Skeels) in morocco as revealed by SSR markers: Implication for conservation

Australian Journal of Crop Science ◽

10.21475/ajcs.17.11.10.pne602 ◽

2017 ◽

Vol 11 (10) ◽

pp. 1304-1314 ◽

Cited By ~ 3

Author(s):

Chaimaa Yatrib ◽

◽

Bouchra Belkadi ◽

Leila Medraoui ◽

Ouafae Pakhrou ◽

...

Keyword(s):

Genetic Diversity ◽

Population Structure ◽

Ssr Markers ◽

Argania Spinosa ◽

Argan Tree

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Early Survival and Growth of Russian Pinus sylvestris L. in Canada

The Forestry Chronicle ◽

10.5558/tfc46325-4 ◽

1970 ◽

Vol 46 (4) ◽

pp. 325-328

Author(s):

A. H. Teich ◽

M. J. Holst

Keyword(s):

Pinus Sylvestris ◽

Scots Pine ◽

High Performance ◽

Jack Pine ◽

Stem Form ◽

Growth And Survival ◽

Growing Seasons ◽

Survival And Growth ◽

Continental Climate ◽

Better Than

Scots pine provenances from Russia were grown in Ontario at Longlac, Dorset and Chalk River, and in Saskatchewan at Prince Albert and Indian Head. After eight growing seasons in the field all provenances survived well. The three tallest, Orel, Woronesh and Kiev provenances, grew considerably taller than the others, and at Prince Albert, where native jack pine was also grown, the growth and survival of these provenances was also better than that of jack pine. If further studies show that this high performance persists and that stem form is commercially acceptable, seedlings from these three provenances may be useful for reforestation in those parts of Canada with a continental climate.

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Beyond direct neighbourhood effects: higher-order interactions improve modelling and predicting tree survival and growth

National Science Review ◽

10.1093/nsr/nwaa244 ◽

2020 ◽

Author(s):

Yuanzhi Li ◽

Margaret M Mayfield ◽

Bin Wang ◽

Junli Xiao ◽

Kamil Kral ◽

...

Keyword(s):

Species Diversity ◽

Temperate Forest ◽

Species Coexistence ◽

Biotic Interactions ◽

Higher Order ◽

Individual Level ◽

Pairwise Interactions ◽

Tree Survival ◽

Survival And Growth ◽

Tree Performance

Abstract It is known that biotic interactions are the key to species coexistence and maintenance of species diversity. Traditional studies focus overwhelmingly on pairwise interactions between organisms, ignoring complex higher-order interactions (HOIs). In this study, we present a novel method of calculating individual-level HOIs for trees, and use this method to test the importance of size- and distance-dependent individual-level HOIs to tree performance in a 25-ha temperate forest dynamic plot. We found that full HOIs-inclusive models improved our ability to model and predict the survival and growth of trees, providing empirical evidence that HOIs strongly influence tree performance in this temperate forest. Specifically, assessed HOIs mitigate the competitive direct effects of neighbours on survival and growth of focal trees. Our study lays a foundation for future investigations of the prevalence and relative importance of HOIs in global forests and their impact on species diversity.

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Stand density, drought, and herbivory constrain ponderosa pine regeneration pulse

Canadian Journal of Forest Research ◽

10.1139/cjfr-2019-0248 ◽

2020 ◽

Vol 50 (9) ◽

pp. 862-871 ◽

Cited By ~ 3

Author(s):

Thomas E. Kolb ◽

Kelsey Flathers ◽

John B. Bradford ◽

Caitlin Andrews ◽

Lance A. Asherin ◽

...

Keyword(s):

Pinus Ponderosa ◽

Ponderosa Pine ◽

Seedling Survival ◽

Stand Density ◽

Survival Duration ◽

Northern Arizona ◽

Growing Seasons ◽

Pine Regeneration ◽

Stand Thinning ◽

Survival And Growth

Trees in dry forests often regenerate in episodic pulses when wet periods coincide with ample seed production. Factors leading to success or failure of regeneration pulses are poorly understood. We investigated the impacts of stand thinning on survival and growth of the 2013 cohort of ponderosa pine (Pinus ponderosa Douglas ex P. Lawson & C. Lawson) seedlings in northern Arizona, United States. We measured seedling survival and growth over the first five growing seasons after germination in six stand basal areas (BAs; 0, 7, 14, 23, 34, and 66 (unthinned) m2·ha−1) produced by long-term experimental thinnings. Five-year survival averaged 2.5% and varied among BAs. Mean survival duration was longer in intermediate BAs (11 to 16 months) than in clearings and high BAs (5 months). The BAs of 7, 14, and 23 m2·ha−1 had >2600 5-year-old seedlings·ha−1. In contrast, regeneration was lower in the clearing (666 seedlings·ha−1) and failed completely in the 34 m2·ha−1 and unthinned treatments. Seedling survival was highest during wet years and lowest during drought years. Many surviving seedlings had no net height growth between years 4 and 5 because of stem browsing. Results indicate that natural regeneration of ponderosa pine is influenced by stand BA, drought, herbivory, and interactions between extreme climatic events.

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Short-term Performance of Two Sulfonylurea Herbicides: Efficacy, Seedling Survival, and Growth

Northern Journal of Applied Forestry ◽

10.1093/njaf/12.2.80 ◽

1995 ◽

Vol 12 (2) ◽

pp. 80-85

Author(s):

Phillip E. Reynolds ◽

Micheal J. Roden

Keyword(s):

Black Spruce ◽

Seedling Survival ◽

Stem Volume ◽

Silty Clay ◽

Herbicide Application ◽

Short Term ◽

Growing Seasons ◽

Survival And Growth ◽

Term Performance ◽

Survival Of Seedlings

Abstract Metsulfuron (ALLY or ESCORT), 36 and 72 g ai/ha (~ 0.5 and 1.0 oz ai/ac), and sulfometuron (OUST), 150, 300, and 450 g ai/ha (~ 2.1, 4.2, and 6.3 oz ai/ac), were applied to a northern New Brunswick clearcut (silty clay loam and silty clay soils) to reduce raspberry competition. Treatment, using skidder-mounted herbicide application equipment, occurred in May and August 1986, with planting of 2+2, bareroot, black spruce seedlings in June 1986 and in June 1987. Seedling survival and growth were measured yearly for 5 growing seasons after planting. By August 1991, raspberry cover was less in some treatments than in controls. Survival of seedlings planted 1 month after spring treatments was less than controls, and no significant stem volume increases were observed. Survival of seedlings planted approximately 1 yr after spring treatments was greater than that of control seedlings. Survival of seedlings planted after some summer treatments also was poor, and no significant stem volume increases were noted for seedlings planted after site preparation with sulfometuron. Optimal stem volume increases over control seedlings were observed for seedlings planted 1 yr after spring sulfometuron treatment. These increases occurred sooner than for seedlings planted 1 yr after spring metsulfuron treatment or after summer metsulfuron treatment. Fifth-year stem volume for these seedlings was correlated with raspberry cover (r² = 0.44), decreasing as raspberry cover increased. We conclude that the use of other less expensive silvicultural herbicides may provide equally effective raspberry control and better black spruce seedling survival and growth. North. J. Appl. For. 12(2):80-85.

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