The experiments were led to study the effect of pretreatments and their duration on germination behavior of three Acacia species A. cyanophylla Lindl., A. farnesiana L. and A. decurrens Willd. by analyzing three parameters (GP: germination percentage; MGT: germination mean time (days) and GRI: germination rate index) for various times of incubation (5, 10 and 15 days) in Petri dishes. Pre-sowing treatment included immersion in concentrated sulphuric acid for 60, 90 and 120 minutes. The sowing in distilled water (Control) had no positive effect on the germination induction. Generally, the seed pretreatments were very useful to improve germination. Time of immersion significantly (P < 0.0001) affected GP, MGT and GRI in all species. Increasing the duration of sulphuric acid immersion (from 60 to 120 min) improved the germination percentages for A. cyanophylla and A. farnesiana seeds to (98% and 99%), respectively. However, increasing this duration had a negative effect on A. decurrens seed germination, reducing the final germination percentage from 97% at 60 minutes of immersion to 43% at 120 minutes.

Oriental beech established in the Hyrcanian forests, is a valuable tree whose habitats are constantly exposed to destructive factors which change the nutritional status of soil and leaves. Analysis of foliar elements is a commonly used method for studying tree nutrient status that indicates site's quality. Foliar analysis of beech (Fagus orientalis Lipsky) was carried out in Kojour (Mazandaran) in order to assess the nutritional balance of trees in a damaged forest site (a direct result of livestock grazing and anthropogenic perturbations). Sunny leaves of dominant trees were taken in August and foliar concentration of macroelements, N, P, Ca, K and Mg were measured. The diagnosis and recommendation integrated system (DRIS) analysis was applied for evaluating the nutritional state. The results showed deficiency with K and P in disturbed stands. Nutrient Balance Index (NBI) indicated imbalance in nutrient status. These results suggest the usefulness of DRIS for foliar tissue analysis as an indicator of nutritional status and elemental stress in natural forests.

When it comes to testing for differences in seedling survival, researchers sometimes make a Type II statistical error (i.e. failure to reject a false null hypothesis) due to the inherent variability associated with survival in tree planting studies. For example, in one trial (with five replications) first-year survival of seedlings planted in October (42%) was not significantly different (alpha = 0.05) from those planted in December (69%). Did planting in a dry October truly have no effect on survival? Authors who make a Type II error might not be aware that as seedling survival decreases (down to an overall average of 50% survival), statistical power declines. As a result, the ability to declare an 8% difference as “significant” is very difficult when survival averages 90% or less.  We estimate that about half of regeneration trials (average survival of pines <90%) cannot declare a 12% difference as statistically significant (alpha = 0.05).  When researchers realize their tree planting trials have low statistical power, they should consider using more replications.  Other ways to increase power include: (1) use a one-tailed test (2) use a potentially more powerful contrast test (instead of an overall treatment F-test) and (3) conduct survival trials under a roof.

Variable-radius sampling techniques are commonly used during forest inventories. For each sample tree at a particular sampling point, diameter and height(s) are measured and then weight is estimated using established equations.  Heights can require a fair amount of time to measure in the field.  Separating the weight per acre estimate into two components; average basal area per acre and WBAR (individual tree weight-basal area ratio) across all points, can often lead to more efficient sampling schemes. Variable-radius sampling allows for a quick estimate of basal area per acre at a point since no individual tree measurements are needed.  If there is a strong relationship between weight and basal area, then by knowing basal area you essentially know weight.  Separation into two components is advantageous because in most cases there is more variability among basal area estimates per point then there is in WBAR. Hence, you can spend more resources establishing many points that only estimate basal area – often called “Count” points. “Full” points are those where individual tree measurements are also conducted. There is little published information quantifying the impacts on basal area, weight, etc., estimates among different “Full/Count” sample size ratios at the same site. Inventories were examined to determine this method’s applicability to loblolly pine plantations in southern Arkansas and northern Louisiana. Results show there is more variability among basal area estimates than WBAR and that the amount of trees being “intensively” measured is excessive.  Based on these four plantations, a “Full” point could be installed ranging from every other point to every fifth point depending on site conditions and the desired variable.

Autochthonous poplar species were neglected during the intense establishment of plantations using various selected clones. This paper presents the results of seedlings quality comparison of two autochthonous poplars and three clones of poplar (129/81, I-214 and PE 19/66) in order to determine capabilities for mass production of autochthonous poplar seedlings. The seedlings of clone 129/81 have the largest diameter and height, and the seedlings of black poplar shows the smallest values. Seedlings of gray poplar have similar values as seedlings of clone PE 19/66, except diameter on 1 m above the ground. Clone I–214 shows least values relative to seedlings of other two clones. The results obtained in this study indicate the possibility of mass production of autochthonous poplar seedlings. Considering that the seedlings are used primarily for the purposes of conservation, the existing manufacturing technology, as well as the applicable standards of quality seedlings, which are used for highly productive clones of poplar, should be adapted to the production of a large number of genotypes.

Turkey has 9.64 million hectares of unproductive forests 43% of the total forest area according, to 2016’ forest inventory. Forest establishment including afforestation, reforestation, rehabilitation and private plantation is the most important method to convert unproductive forest into productive ones, and also to increase present productivity of product forest by improved seed and seedling materials. Turkish forest establishment is examined based on past, present, and future perspectives according to forest inventory from 1946 to 2015 in the present study to contribute present and future establishment.

The history of reforestation in Slovakia is long and rich; from reforestation by seeding, through the small forest nurseries, reforestation of extreme degraded and high-mountain sites to the current The Act on forest reproductive material, nursery centers and reforestation of large windthrow areas. After brief introduction of the history, rather large part of this review is dedicated to the current nursery and especially reforestation practices – planning, pre-planting site preparation, seeding and planting techniques, post-planting care, monitoring of planting performance. Recent nursery and planting research activities are given very shortly. Perspective nursery (e.g. improvement of seedlings’ quality by inoculation with beneficial microorganisms, vegetative propagation) and reforestation treatments and practices (e.g. the use of larger amount of container-grown seedlings, application of hydrogels and ectomycorrhizal fungi, progressive seeding technique, underplanting) are relatively in detail but of course not comprehensively discussed finally. Despite of the lack of a complex reforestation strategy and current and possibly future financial sources and personnel limitations, the introduced perspective practices should contribute to successful solution of reforestation challenges following from endangering the forests by climate change.

The forest has always played a big part in Belarus. At present it covers about 40% of area of the country`s territory. Predominantly the forests are of natural origin. The main species are Pinus sylvestris L. (Scotch pine), Betula pendula Roth (European white birch) and Picea abies (L.) Karst. (Norway spruce). The other valuable species are Quercus robur L (English oak), Alnus glutinosa (L.) Gaertn. (European alder), Larix decidua Mill. (European larch), Abies alba Mill. (Silver fir). The history of the forest management in Belarus showed that over last 150 years the enormous damage to the qualitative and quantitative composition of forests had been made by wars and reconstruction of destroyed industry. The taken reforestation measures allowed to increase the forest area significantly, however, the work on improving of forests` quality requires further development. At present the artificial forest regeneration prevails in the republic. Over the past five years the volumes of established forest plantations range from 21 to 25 thousand hectares annually, the areas of assistance to the natural regeneration – from 4 to 6 thousand hectares annually. By now there are about 1,700 ha of the forest seed orchards, 2,795 plus trees and 1,125 ha of the plus stands in the republic. The cultivation of planting stock for needs of reforestation is carried out on 73 forest tree nurseries with a total area of 1,440 ha. Annually over the last five years there were grown from 270 to 317 million seedlings and transplants, among them 30-35 million seedlings were grown in greenhouses and about 6 million were container seedlings. In order to improve the gene resource and thereby to increase the productivity and quality of future forests, the tendency of forest plantations` prevalence in the reforestation process of Belarus should remain, but in this case the volumes of partial forest plantations should be increased.

Nigeria, a country in West Africa, sits on the Atlantic coast with a land area of approximately 90 million hectares and a population of more than 140 million people. The southern part of the country falls within the tropical rainforest which has now been largely depleted and is in dire need of reforestation. About 10 percent of the land area was constituted into forest reserves for purposes of conservation but this has suffered perturbations over the years to the extent that what remains of the constituted forest reserves currently is less than 4 percent of the country land area. As at today about 382,000 ha have been reforested with indigenous and exotic species representing about 4 percent of the remaining forest estate. Regrettably, funding of the Forestry sector in Nigeria has been critically low, rendering reforestation programme near impossible, especially in the last two decades. To revive the forestry sector government at all levels must re-strategize and involve the local communities as co-managers of the forest estates in order to create mutual dependence and interaction in resource conservation.

Reforestation in Algeria has been recognized as a priority in different programs for the development and enhancement of forest heritage. Degradation factors of forest and soil contribute significantly to the decline in land values. The Algerian forests in the past, during the colonial period suffered considerable degradation. The degraded forest heritage has been undertaken with serious programs since independence. Several programs for the development of the forest sector through reforestation have been carried out. Unfortunately, the achievements were still below expectations. The launch of the National Reforestation Plan in 2000 has given the forestry sector a new lease of life with a vision that incorporates the productive aspect of reforestation, the industrial aspect, and the recreational aspect. Before the end of the NRP timeline, significant reforestation projects are completed. In a future projection, reforestation is integrated into the land use planning within the framework of the National Plan of Land Use Planning.

Following the Second World War, the number of Cupressaceae plantations in Japan increased, in accordance with government policy for the restoration of timber resources and conservation of soil and water. Currently, these even-aged plantations occupy approximately 44% of the forested area and 24% of the national land area of Japan. Although many of these plantations have become available as timber resources, there are several silviculture-related problems associated with reforestation following clear-cutting of these plantations. The abundant annual precipitation in Japan allows for dominance by competitive vegetation, which makes natural regeneration difficult and increases the cost of silvicultural operations during and after the planting of seedlings. Because the number of seedling producers has decreased, there has been little incentive to keep seedling production techniques up to date. Additionally, damage to planted seedlings by the overabundant sika deer (Cervus nippon) population has increased dramatically in the last dozen years or so. To determine how to overcome these difficulties, various studies are underway in Japan. For example, seedling studies have examined the relationship between seedling size and competitive ability with other species in reforested areas, and have led to the development of lower-cost systems to produce customized Cupressaceae seedlings, as well as measures to minimize transplanting damage to seedlings. Previous studies have shown that no-weeding operations might lower the risk of sika deer browsing seedlings, although this silvicultural countermeasure may potentially reduce seedling growth. Studies have also examined the types of physical protection against sika deer browsing that are most efficient. We must combine these findings into a unified silvicultural system for successful restoration via lower-cost plantations.

The historical development of afforestations in Bulgaria was investigated. Some of the more important decisions and events which determine the correct state policy in the field of afforestations are pointed out. The most significant achievements are in: erosion control, incl. water tank protection from silting up; increasing the tree volume and forest growth; protection of agriculture via forest protection belts; landscape improving. The social importance for more employment and improvement of means of livelihood is mentioned. Proved reasons for decreasing the afforested areas since 1980s are given. The main mistakes and problems are mentioned as well as the changes in the afforestation policy and future challenges.

This paper presents data about forestry and reforestation in the Republic of Macedonia. The country is characterized with great diversity of natural conditions and rich floral and faunal biodiversity Forests in Macedonia cover 38% of its territory. About 71% represent coppiced and degraded and 29% tall forests. Historical, social and natural conditions caused gradual deforestation, forest and land degradation. Foundations of artificial afforestation were laid in the first decade of XX century. First reforestation started already in 1913/14 and continued, with various intensity, in the next decades. In the period between two world wars a foundation of modern forestry was established, as forestry education, scientific work etc., to help dealing with reforestation of waste bare and erosive lands. The most intensive reforestation was performed in 1971-1990 and during the following years significantly decreases. There is room for improving of some aspects of the reforestation, in aim to improve survival and development of the young stands.

In the past, the entire region of Poland was overgrown by forests. Due to economic changes, the forest cover was reduced to 40% in the 18th century and 21% after the Second World War. After the war, Polish foresters undertook considerable efforts to increase the forest cover to 30.8% by 2015. Polish forests are characterized by the dominance of oligo- and mesotrophic coniferous species (68.7%). This include the pioneer species, Scots pine. It covers approximately 60% of the area. The species composition of Polish forests determined the dominance of artificial regenerations. However, the currently prevailing direction of forest culture is natural regeneration. This tendency is related to “greening” of the forest management, the priority of durability over productivity and culture of multifunctional forests. A natural or seminatural direction of forest culture is being promoted. Renewal of the species such as fir, beech, oak, or spruce from the last stages of succession have always taken place in a natural manner, whereas the statistics are generated by the dominant species preferring open areas during renewal. Currently, the scale of natural regenerations of the pine is increasing. It is increasingly common to value the favorable economic aspect of natural renewal of the species, and the experience of practitioners supported by scientific research increase the likelihood for success. In Poland, the majority of methods of regeneration proceedings (forest cutting) and the law are directed at obtaining and promoting natural renewal. Independent of the concept of natural renewal promotion, the location of Poland in the intermediate climate zone, between the influence of oceanic and continental climates, resulted in the formation of valuable tree stands with high flexibility and tolerance to growth conditions. They are divided into seed stands, excluded stands, and timberlands. Thus, Poland is in possession of a great base for seed collection. At the beginning of 1990s, a rapid need for container seedlings occurred due to numerous disasters (wind-broken trees, gradations). Currently, in Poland, 17 field nurseries are in operation producing 1–10 m seedlings. In 1992, Poland received a loan from the World Bank to conduct afforestations and the “National Program for Increasing the Forest Cover” was started. The main objective of the plan is to increase the forest cover to 30% in 2020 and 33% in 2050. Within the program, it is planned to include vegetation of the natural succession in the area of approximately 80,000 ha.

Planted forests are an important source of various services (economic, environmental, and social) with increasing portion in the total world’s forest area. Genetic diversity is fundamental for success and sustainability of planted forests. Facing the concern of the reduction of genetic diversity in planted forests, this study offers a review of evidence on comparisons between the levels of genetic diversity in forests established by different regeneration methods. A total of 34 papers comparing genetic diversity in natural forests versus various regeneration methods of 24 tree species examined by the range of markers are reviewed. In most cases, there are no significant differences in genetic diversity between natural and planted forests, followed by an almost equal number of cases with decreased and increased level of genetic diversity. The loss of rare alleles, but also new alleles are reported in planted forests. Although the origin of planting material in the most cases are unknown, the size of parental population is determinant for the level of genetic diversity in the new forest, with the provenancing and seed collection strategy as the most important management practices in planting projects.