Survival Of Planted Trees Research Articles

Drivers of tree establishment in planted windbreaks and riparian buffers: A case study of farms in southern Quebec, Canada

Successfully established windbreaks and riparian buffers contribute to protection of soils, crops, watercourses and biodiversity, and help to combat climate change. To improve establishment success of trees planted to form these agroforestry systems, identifying the factors influencing their survival and growth is crucial. We related survival and size of trees planted in windbreaks and riparian buffer strips to 23 abiotic, biotic, structural and technical explanatory factors using multiple generalized linear models. We sampled 52 windbreaks and 26 riparian buffer strips planted in different cultivated fields in southern Quebec (Canada). We analyzed volunteer vegetational composition in the tree planting right-of-way relative to eight explanatory factors. Average survival of planted trees was 86.4% and varied mainly with planting site; tree survival was negatively and significantly correlated with soil pH. We modelled correlations between size of the ten most frequently occurring tree species and 20 explanatory factors, of which six were significant, i.e., method of volunteer vegetation control, soil texture, soil preparation before planting, volunteer vegetation abundance, tree row structure and agroforestry system type (windbreak vs riparian buffer). Relative abundance of different functional types of volunteer vegetation was influenced mainly by the age of agroforestry systems. To increase tree establishment success in winbreaks and riparian buffers, species must be properly selected for planting based upon edaphic conditions, while implementing soil preparation prior to planting and maintaining sufficient spacing between trees to optimize long-term growth. Our results suggest that tree establishment in windbreaks and riparian buffers within an intensive agricultural context should not be perceived as a barrier to their adoption.

Rehabilitation options for degraded secondary forests in Adiyo district of Kaffa zone, Southwest Ethiopia

Forest degradation is a very serious environmental problem. It leads to decline of biodiversity and ecosystem services. Thus, the objective of the study was to identify rehabilitation options for the degraded secondary forest in the Adiyo district in southwest Ethiopia. Data were collected from 30 quadrats (20 m × 20 m) across five treatments established for three years to examine stand structures, diversity, regeneration status of woody species, and enriched planting. The diameter at breast height (DBH) and height (H) of woody species were measured in the main quadrats and their seedlings and sapling were counted in the five subplots (4 m × 4 m) inside each main quadrat. A complete random design with three replications was employed to examine the growth performance and survival of planted trees with two permanent blocks having an area of 10,000m2. The diversity and evenness of woody species were estimated using Shannon Diversity Index (H') and Evenness (E). The importance value index (IVI) of woody plants was calculated to identify the status of ecologically significant species. A total of 30 woody species belonging to 27 genera and 20 families were recorded. The dominance value in the combination of assisted and enrichment of planting (CAREP) treatment reached 3.7 times higher than in open disturbed (OD) forest and exhibited a significant difference at p < 0.05. Shannon (H') and Simpson (D) diversity values also exhibited maximum in CAREP (H' = 2.60, D = 0.91) than other treatments. The highest IVI of woody species, the healthy population structure pattern, and potential regeneration species were found in CAREP treatment. Similarly, seedlings of H abyssinica, P. africana, and S. abyssinica demonstrated higher growth performance (3.41 to 4.35 m) and survival rate (76 to 85%) in the CAREP than in other treatments. In conclusion, the stand structure, diversity and regeneration status of woody species as well as the survival rate and growth performance of enriched species exhibited improvement in the CAREP treatment. It should be the best rehabilitation option for degraded secondary forest and need to be promoted for further adoption.

Socio-economic and ecological outcomes of a community-based restoration of peatland swamp forests in Peninsular Malaysia: A 5Rs approach

Restoration of degraded forest lands is a global priority that aims to restore ecosystems and their functions in ways that provide multiple socio-economic benefits. The Selangor State Forestry Department (SSFD) of peninsular Malaysia in collaboration with an NGO, local people and other stakeholders had been implemented a community-based restoration of degraded peat swamp forest (1000 hectare) programme in Raja Musa Forest Reserve, North Selangor since 2008. However, socio-economic and ecological impacts of this restoration programme are yet to study fully. In this pioneer study, we followed 5Rs approach to peatland restoration and assessed rewetting status (R1), reduction of fire incidences (R2), revegetation (R3), revitalization (R4) and reporting and monitoring (R5) to understand socio-economic and ecological outcomes of the programme. Data on R1, R2, R3 (restoration approach), R4 (qualitative data on socio-economic outcomes) and R5 (management actions and stakeholders’ participation) were collected through four focus group discussions, five key informant interviews, review of NGO’s documents and a stakeholders’ workshop. Quantitative data on R4 (local peoples’ willingness to contribute (WTC) and socio-economic impact (e. g. benefits, education, awareness) were collected through structured interviews of 200 randomly selected households in four surrounding villages. Data on R3 (ecological outcomes- survival rate and growth of planted trees, status of natural regeneration) were gathered through a series of vegetation survey. Restoration project created jobs (e. g. patrolling) and small business (e. g. forest nursery) opportunities for local people, and enhanced tourism, nature education and research in RMFR thus contributed to locals’ socio-economic development (R4). Local people were WTC to tree planting and maintenance (69 %), canal blocking and maintenance (26 %), forest vigilance (34 %), fire control (35 %), trail construction (27 %), and education and awareness creation (40%) voluntarily without remuneration (R1, R2, R3). The SSFD and NGO adopted an innovative approach of PSF restoration where volunteers (local people and other stakeholders) participated in canals blocking to keep PSF wetted, monthly tree planting events, and education and awareness creation campaigns (R1, R3). Canal blockings helped to maintain a mean ground water level of − 24.96 cm. Due to continuous motivation and awareness creation among surrounding villagers, fire incidents in RMFR were reduced (R2). Between 2008 and 2019, 323.72- hectare plantations were developed mainly with Euodia redlevi tree species and few trees of Shorea leprosula, Myristica lowiana and M. pruinose (R3). Selection of species was done by the SSFD and NGO without input from local people (R5). The mean survival percentage of planted trees was 65%. Mean annual increment (MAI) of diameter and height of E. redlevi decreased from younger plantations (3-year) toward older ones (5-, 7-year) (R3). Overall, MAI (dbh and height) across four tree species between age groups was found significantly different (p = 0.001). Regeneration study identified 16 tree species with an average density of 17,798. E. redlevi was dominant, but only 10.6 % of its regeneration attained young tree stage (R3). Suggestions are made to expedite restoration with diverse tree species (R3) with effective participation of local people (R5) and to ensure post-planting maintenance for greater survival of planted trees (R1, R2, R3).

Canopy openness affects microclimate and performance of underplanted trees in restoration of high-elevation tropical pasturelands

Restoration of abandoned, high-elevation pastures is needed across many ecosystems. Diverse abiotic and biotic stressors often limit establishment of native trees species, however, justifying the need for novel approaches to alleviate such stressors. Freezing damage often negatively impacts survival of planted trees across temperate landscapes and on some high-elevation tropical restoration sites, such as for Acacia koa (koa) in Hawaii, USA. Koa performs poorly under forest canopies, a potential limitation to the use of nurse trees for establishment on frost-prone sites. Using a heterogeneous canopy of a non-native conifer, Cryptomeria japonica, we underplanted koa seedlings along a simulated range of canopy shelter levels in combination with field fertilization. We tested the effect of a canopy cover gradient and nutrient availability on frost avoidance and tolerance responses, as well as the potential to harness koa's developmental plasticity to optimize growth and survival. C. japonica canopy cover provided protection from frost damage, with increased sheltering under greater canopy closure. When combined with fertilization, increasing canopy closure reduced frost damage and increased koa growth. Although we observed limited frost damage in our study, leaf-level soluble sugars increased during the winter and in more open microsites, reflecting a potential mechanism for frost tolerance in this tropical species. We conclude that frost-tolerant conifers used as nurse trees represent a potential tool to help establish native tree species on high-elevation, frost-prone sites.

Challenges in tree-planting programs

Climate Numerous tree-planting projects have been launched globally, but will they really help to improve environmental conditions? In a Perspective, Holl and Brancalion discuss the issues with tree-planting projects, including reforestation with non-native species, limited recovery of biodiversity, competing land uses, and lack of long-term management to ensure survival of planted trees. Although tree planting can be beneficial, there are numerous challenges to be overcome before this practice can be shown to improve the environment. Science , this issue p. [580][1] [1]: /lookup/doi/10.1126/science.aba8232

Positive outcomes between herbivore diversity and tree survival: Responses to management intensity in a Patagonian forest

Sustainable forest management aims to both enhance biodiversity and tree productivity. However, trade-offs may exist between these objectives, e.g. arthropod diversity and associated arthropod herbivory can reduce tree growth and survival. Tree productivity and biodiversity may also show non-linear responses to management intensity, making applied recommendations even more challenging. We studied the effects of harvesting intensity for firewood extraction in a northern Patagonian forest (Argentina) on leaf damage diversity (as a proxy of arthropod folivore diversity), leaf damage frequency, growth and survival of planted trees of Nothofagus obliqua for timber purpose. We randomly applied four levels of harvesting intensity (0, 30, 50, and 70% of basal area removal) in experimental plots and we followed the responses on the focal planted tree species during two growing seasons. After harvesting, air temperature and photosynthetic active radiation increased, while relative humidity decreased, with harvesting intensity. Leaf damage diversity and frequency showed non-linear responses to harvesting intensity, both achieving its highest values at intermediate harvesting intensities (30% and 50% of basal area removal). Such responses were consistent for contrasting feeding guilds, using different diversity indices, and during the two study growing seasons. Interestingly, leaf damage diversity and frequency were positively and strongly correlated across the plots. Despite great leaf damage frequency (around 45% of the leaves were damaged), plant survival was also highest at intermediate harvesting intensities during the two years. Planted trees also grew more at intermediate harvesting intensities during the second year, but increased linearly with harvesting intensity during the first year. Hence, at intermediate harvesting intensity, no trade-off was observed between arthropod biodiversity and planted tree sapling survival and growth. In northern Patagonia, trees may face less competition for light and soil resources at intermediate harvesting intensities, while at high harvesting intensities water stress typical of dry Patagonian summers could reduce tree survival. Such benefits were not offset by the greater leaf damage (associated with enhanced damage diversity) observed at intermediate harvesting intensities. Therefore, intermediate levels of management intensity can provide the double service of increasing arthropod diversity and maximizing tree survival and growth, especially during the most critical establishment period.

Flood Exposure Affects Long-Term Tree Survival in Compensatory Mitigation Wetlands

Survival of planted trees is commonly used as a performance metric for compensatory mitigation wetlands. However, establishing floodplain forest through planting is difficult due to flood-induced tree mortality. We used multiyear tree census and hydrologic data from 17 compensatory mitigation projects in Illinois, USA, to relate planted and volunteer tree establishment to flood frequency, depth, and duration. Annual survival of planted trees decreased with greater annual maximum flood depth and duration. By the end of official compliance monitoring, sites with greater flood exposure had greater planted tree mortality. We resurveyed 10 sites that were at least 10 years old, and found that long-term tree survival was significantly lower in sites with greater flood exposure. Naturally colonizing trees differed in species composition from planted trees; specifically, wind dispersed species were well-represented among volunteer trees, whereas hard mast species were absent. There was no clear relationship between volunteer tree recruitment and measured flood variables. Across all sites, compliance with tree survival standards was poor, but influenced by hydrologic conditions. Current performance standards for tree survival may be unrealistic in restored wetlands that are exposed to long-duration floods. Regulators and practitioners should seek alternative methods to establish desired floodplain forest structure and function.

Quality of tree seedlings produced in nurseries in Malawi: an assessment of morphological attributes

Survival of planted trees in Malawi is very low and this is attributed to many factors including the use of poor quality tree seedlings. A survey was conducted to assess the quality of tree seedlings produced by various nurseries. The survey covered 55 nurseries in four districts in central Malawi comprising 18 private, 26 communal and 11 institutional nurseries. A total of 1,500 tree seedlings were assessed for morphological attributes i.e. root collar diameter (RCD), height, root and shoot weight, shoot-to-root ratio (S:R), sturdiness quotient, Dickson’s Quality Index (DQI) and root deformity. Differences between the three nursery types were significant (p < 0.05) for some of the parameters. Overall, 33%, 58% and 67% of assessed seedlings in communal, institutional and private nurseries, respectively, had the recommended S:R ratio of less than 2, while for sturdiness quotient, 8%, 67%, and 58%, respectively, of the seedlings had less than the recommended threshold value of 6. A similar pattern was observed for RCD and DQI. Prevalence of root deformities was highest in institutional nurseries (47.5%), followed by private (45.5%) and communal nurseries had the lowest (42.6%). Given that all three nursery types have apparent, but sometimes different seedling quality issues, building knowledge and technical capacity is needed across all the nursery operators.

Alternative field fertilization techniques to promote restoration of leguminous Acacia koa on contrasting tropical sites

Field fertilization can promote early growth and survival of planted trees on degraded pastures and agricultural lands where low soil fertility and high herbaceous competition inhibit regeneration success. Controlled-release fertilizers (CRF) may improve the effectiveness of fertilization relative to that of immediately available fertilizers (IAF) because CRF gradually release nutrients directly to the root zone, thereby limiting nutrient losses. Despite past research in boreal and temperate landscapes, few studies have tested the efficacy of similar applications in tropical systems where year-round high temperatures can increase release rates of CRF and intensity of competing vegetation. On two contrasting sites on the Island of Hawaii, USA, we evaluated early growth and survival responses of koa (Acacia koa Gray), a fast-growing legume, using ten treatments: a control, four IAF formulations, and five rates of polymer-coated CRF (15N-9P-12K; 15–75g). At Pahala, a productive site, we detected no significant growth, survival, or foliar nitrogen (N) or phosphorous (P) responses to the fertilizer treatments. At Volcano, a rockier and cooler site on younger soil, height increased by 36–49% for the highest performing CRF and IAF relative to the control; diameter likewise increased by 55–92%. Growth responses appeared to be a result of P fertilization rather than N. The highest performing IAF had a reduced survival rate relative to the lowest CRF (46% vs. 83%). Although total nutrient application rates were much lower for CRF, our results suggest that on tropical restoration sites, CRF may promote seedling performance at least equally to that of IAF. There is a need to more carefully evaluate the effects of site-specific interactions that may determine field fertilizer responses, across a range of genera and functional groups.

Long-term effects of stump harvesting on soil properties and tree growth in Scots pine and Norway spruce stands

Effects of stump harvesting on the properties of surface soil and on the density, structure and growth of Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) Karst.) stands were estimated in a field trial in western Finland. The experiment was established in 1977 and measured in 2010. Stems and logging residues were harvested after clear-cutting, and stumps were lifted and removed from half of the experimental area. Sixteen plots were planted with pine seedlings and 16 with spruce. The main effects of stump harvesting were improved survival of planted trees and an increase in natural regeneration. No clearly negative effects were noted in the stand development. Stump harvesting had no or minimal effects on the properties of the organic layer and those of the 0- to 10-cm mineral-soil layer. Soil properties did not differ between tree species. Pine production was higher on plots with stump removal compared to plots without soil treatment.

Reforestation practice for enhancement of ecosystem services on a compacted surface mine: Path toward ecosystem recovery

Re-establishment of trees on surface mine-lands is difficult and their growth is often slow. Compacted spoil and existing vegetation may hinder forest restoration and reduce or delay ecosystem service delivery. We used brush removal, deep tillage, planting native trees, fertilizer, and herbicide applications to speed restoration of 35ha of previously reclaimed and abandoned surface mine-lands in southwestern Virginia, USA. Intermediate measures of success (tree stocking and volume, species richness and evenness) were assessed 2, 3, and 4 years after planting. After two plantings and 3 years of herbicide application, survival of planted trees was 31% (639treesha−1). Volunteer trees such as black locust (Robinia pseudoacacia), sourwood (Oxydendrum arboretum), ash (Fraxinus sp.), and red maple (Acer rubrum) provide additional stocking (539treesha−1), 65% of the total tree volume, and contribute to species richness, indicating that they aid in the recovery of ecosystem services such as carbon sequestration and biodiversity support. Annual volume growth rates are increasing for planted and volunteer trees. However, autumn olive (Elaeagnus umbellata), an exotic invasive shrub, covered 27% (±5.6) of the sampled area and produced greater volume than native trees. Autumn olive and herbaceous vegetation had potentially antagonistic relationships with planted and volunteer trees. Results indicate that the re-establishment of forest cover, comprised of a mix of planted and volunteer trees, is likely across much of the site. Early-successional species will likely dominate in the near term but planted, mid-successional species such as tulip poplar (Liriodendron tulipifera) and oaks (Quercus spp.) will likely remain as components of the new forest.

SURVIVAL AND GROWTH OF UNDER-PLANTED TREES: A META-ANALYSIS ACROSS FOUR BIOMES

The transformation of natural forest regeneration processes by human activities has created the need to develop and implement new models of forest management. Alternative silvicultural systems such as variable retention harvest, partial and patch cuts, and older forest management practices such as under-planting, are used in many forests around the world, particularly in North American oak stands, the boreal and coastal temperate rain forests of Canada and the United States, and in many degraded tropical regions of Asia and the Americas. Specific objectives are pursued in each of these biomes, but some are common to most regions, such as preservation of cover and structure and their associated benefits for natural or artificial regeneration due to moderation of the microclimate, development of optimal light and competition conditions, and reduced predation by herbivores. Shelterwoods are often presented as an alternative to clear-cutting to improve the survival of planted trees. A meta-analysis of published results with randomization tests was performed to test the relationship between overstory density and planted seedling growth and survival. Multiple comparisons were also used to reveal optimal levels of overstory density, if they exist. A majority of studies show that survival and growth improve as stand density decreases to an intermediate level, below which they either drop or stabilize. This level seems optimal in most conditions, as it is also more apt to fulfill other objectives imposed on today's forest activities, such as the conservation of forest processes and structures, and the reconstruction of degraded stands through the accelerated return of mid- to late-successional species.

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Due to increasing environmental pressure, the state of West Virginia has recently changed its regulations that govern reclamation of mountaintop surface mines. The state regulatory authority now requires the development of commercial forestry as the only agronomic post-mining land use acceptable for mountaintop surface mines that seek a variance from returning the land surface to approximate original contour (AOC). The Samples mountaintop surface mine in southern West Virginia has obtained AOC variances and therefore has commercial forestry as a post-mining land use. Operators of the Samples Mine have initiated a reforestation program where about 20,000 trees per year (roughly 20 ha per year) have been planted at the site over the past six years. During 2002, West Virginia University researchers established belt transects (4.8 m wide by 100 to 200 m in length) in 55 plantations at the site to determine survival of planted trees and to evaluate tree height and stem diameter. Evaluations were performed on plantations established in the spring of 1999 and the spring and fall of 2001. In each transect, slope, aspect, and ground cover were measured, and survival and growth of trees were analyzed according to these site conditions. Average tree survival across these three planting seasons and among all tree species was 65%. Black alder (Alnus glutinosa (L.) Gaertn.) was the largest of the planted trees, but sycamore (Platanus occidentalis L.), pine (Pinus spp.), white ash (Fraxinus americana L.), red maple (Acer rubrum L.), and black cherry (Prunus serotina Ehrh.) also showed good growth. Slope was used as a surrogate for soil compaction (steeper slopes tended to be reclaimed with smaller equipment compared to flatter slopes) and tree survival was 75% on slopes >50%, 62% on slopes 31-50%, and 67% on slopes 70% ground cover.

An experiment of revegetation work on the artificially made debris land : Growth and survival of planted trees during the ten years

An experiment of revegetation work on the artificially made debris land : Growth and survival of planted trees during the ten years

Effects of minesoil and seeded herbaceous species on survival of planted trees

ABSTRACT A series of studies to help find environmentally sound methods to reforest surface-mined lands at reduced cost was established on the Muskingum Mine near Cumberland, Ohio. In one study, three minesoil types (graded topsoil, graded and ripped topsoil, and leveled gray cast overburden) were planted with green ash (Fraxinus pennsylvanica)and white pine (Pinus strobus) trees on subplots seeded with various grass and/or legume mixtures either before tree planting in September or at time of tree planting in March. Also, trees were planted on unseeded subplots. After planting, some trees were oversprayed with Simazine to reduce competition from seeded species. A severe drought that began after planting resulted in heavy mortality but striking survival differences were observed among treatments by end of the growing season. Green ash survived best (71 percent)on unseeded cast overburden. Survival was significantly lower on graded topsoil (50 percent)and on other minesoils that were seeded the previous Se...