Broadleaf species dominate Serbia’s diverse forests including the Srem Forest District, where oak regeneration is focused on the Ravni Srem portion of the district. Pedunculate oak (Quercus robur L.) is the dominant species, making up about 50% of standing volume. The most important supporting species in mixed stands are narrow-leaved ash (Fraxinus angustifolia Vahl) and common hornbeam (Carpinus betulus L.). Seeding is used when acorn crops are poor or absent. In good mast years, acorns are incorporated into the soil or sown mechanically (about 450 kg ha^-1), 2 to 5 cm deep in rows 0.7 m apart with acorns spaced 15 to 20 cm in a row. Seeds are manually collected from registered stands and orchards, and subject to quality testing, thermotherapy, and fungicide treatment before storage. Herbicides and arboricides are used to control competition. Fencing protects seeds and seedlings from animals; rodenticides, fungicides, and insecticides are applied as required. Regeneration areas are limited to 56.25 ha, with seed trees left for shelter. Sowing is done in autumn–winter using machines, with acorns spaced in rows. Early competition is controlled by herbicides. Mechanical weeding and fencing continue during the sapling phase. Fire lanes are established and maintained for up to 15 years. Success is measured by seedling establishment and survival after the first growing season. Impacts of invasive plants and animal damage are mitigated by site management and maintaining fencing. Failure is mainly due to unfavorable climatic factors. The moderate-continental climate is expected to experience increased temperature and precipitation by 2040.

Previous afforestation effort, much of which was accomplished with aerial seeding, restored Pinus massoniana Lamb. forests across more than 4 million ha of barren lands and difficult mountainous terrain in Ganzhou, Jiangxi Province, China. This manuscript provides a review of literature reporting the factors that led to forest and site degradation, conventional practices and techniques used to widely establish forest cover of P. massoniana, and post-sowing and plantation management practices used to encourage development and growth of restored P. massoniana forests. Factors known to impede successful seeding of P. massoniana include poor seed quality, harsh soil and site conditions such as soil erosion and droughty soil, unpredictable and extreme weather or climatic events including drought, frost, or excessive rainfall, and insufficient site preparation or plantation maintenance. Procuring high-quality seed, conducting thorough site assessments, and implementing practices that effectively mitigate factors that limit seed germination, seedling establishment, and tree growth are key to successful P. massoniana seeding.

Mexico is the country with the highest number of species of the genus Quercus, but there has been little research on their propagation in nurseries. Quercus crassifolia is distributed across more than 50% of the national territory; however, no studies have been conducted to document its morphological growth and plant quality in nurseries for reforestation and forest restoration. Some of the key factors in plant production, principally in a technified system, are the selection of containers, substrates, and fertilizer doses. This study therefore evaluated two container sizes, two mixtures of organic substrates, and two doses of controlled-release fertilizer. After nine months of growth in the nursery, morphometric parameters of the plants were recorded, and quality indices were determined based on these values. The results showed that container size, substrate choice, and fertilization dose all influenced the quality of the plant produced. With both fertilizer doses, the 25:25:50 substrate mixture of fresh pine sawdust, composted pine bark, and moss peat produced plants with the highest values of height, diameter, and shoot, root, and total dry biomass. Considering the factors evaluated, the use of 200 mL containers with the aforementioned substrate mixture and the addition of 7 g L^-1 of controlled-release fertilizer will produce plants of Quercus crassifolia suitable quality for use in reforestation.

On January 15, 2025, American Forests and Planscape convened the 2025 Reforestation Summit at the Google.org offices in San Francisco, California, U.S. This collaborative event combined American Forests’ decades-long experience in post-fire reforestation planning and implementation with Planscape’s innovative, community-driven forest restoration planning platform. The objective of the summit was to initiate the development of an integrated reforestation tool(s) to support an end-to-end pipeline approach to post-fire reforestation. The summit brought together more than ninety leading scientists—both in-person and virtually—from across the United States to advance the state of reforestation science and practice (Figure 1). We first provide a brief summary of the 2025 Reforestation Summit, then describe the decision support tools (DSTs) that were discussed at the summit, and lastly discuss the next steps and challenges for building out an integrated reforestation tool(s).

We present a novel way of estimating embryo lethals using doubled haploid (dihaploid or DH) female gametophytes grown in tissue culture. This DH-based lethals estimate is hypothesized to be lower than the more common method where lethals are estimated from one generation of selfing. The chief reasoning is the early mortality spike observed for selfed embryos of larch and other genera in the Pinaceae. This early mortality spike occurs at the stage when diploid embryos embed into haploid female gametophyte tissue. However, this stage is missing for DH embryos which grow in a petri dish thus the DH lethals estimate is hypothesized to be lower compared to seed counts. This DH estimate is based on 20,000 haploid female gametophytes cultures from which two surviving diploidized embryos were recovered. Lethals based on diploidized haploids (DH) have not been reported for a conifer previously because, aside from larch, only a few conifer species continue female gametophyte development in absence of pollen. Our chief finding is that, contrary to our hypothesis, the DH-based lethals estimate was similar to lethals estimated obtained from selfed seeds in published studies. Thus doubling haploid female gametophytes can be used to estimate embryo lethals when diploidization is conducted on a massive scale.

This article is aimed as a basic introduction to conifer somatic embryogenesis for someone with a general interest in applications of this technique and/or who is interested in starting some practical work in the field. We also present data from an example study on individual trees’ ability to initiate somatic embryogenesis in Norway spruce (Picea abies). A total of 158 trees were each tested for ability and relative competence to initiate somatic embryogenesis from the zygotic embryos by observing the initiation frequency for ten zygotic embryos from each individual tree. Furthermore, we conducted a case study by following the process for SE plant formation for a selection of 48 cell lines that were monitored through the SE developmental pathway, with data collected on the success rates at different steps. We then evaluated the relative importance of different steps for the outcome of plant formation and yield.

In the context of variable climate conditions, selecting high-quality Sessile oak (Quercus petraea (Matt.) Liebl.) reproductive material is crucial for sustainable forestry. This research aimed to assess the genetic potential of 86 selected plus trees by analyzing seedling morphological characteristics and quality indices. The ultimate goal was to identify the most promising genotypes for establishing seed orchards. Root collar diameter (D), seedling height (H), stem dry mass (SDM), and root dry mass (RDM) were measured under uniform nursery conditions. The following derived indices were calculated: seedling height to root collar diameter ratio (H/D), stem dry mass to root dry mass ratio (SDM/RDM), and Dickson’s quality index (DQI). Descriptive statistics, one-factorial analysis of variance (ANOVA) and Pearson correlation analysis were performed as well. The results showed significant variability in all observed morphological characteristics and quality indices among half-sib families, confirming a strong genetic influence. Correlation analysis indicated strong positive relationships between DQI and all primary morphological characteristics (r≤0.94), confirming DQI as the most effective integrative indicator of seedling quality. The combined ranking of the half-sib families, based on DQI, H/D, and SDM/RDM, identified those with optimal morphological characteristics, including an optimal H/D ratio, balanced SDM/RDM, and a high DQI value. The identified superior half-sib families represent valuable genetic material for the establishment of future seed orchards, thereby contributing to the production of better-quality seedling material and to improved forest ecosystem resilience under climate change.

The present study was carried out in 16rd year afforestation sampled from southern Turkey of Taurus cedar (Cedrus libani A. Rich) and Crimean juniper (Juniperus excelsa Bieb.). Variation, competition and correlation were examined based on seedling height and stem diameter at base data collected from two samples areas 500 m² each. Growth performances were different at the areas for the species, while averages of Taurus cedar (223.6 for height and 65.3 mm for stem diameter at base) had higher than Crimean juniper (106 cm and 58.5 mm) in total areas. The results emphasized importance of species selection in afforestation. Significant (p<0.05) differences between areas and species were found according to results of analysis of variance. Positive and significant phenotypic correlation (p<0.05, r>0.52) was estimated between the characteristics in both species and areas. It could be used for tending in afforestation areas.

An adult tree of Larix decidua Mill., European larch, was produced from doubling one haploid female gametophyte. Whether this tree can produce normal male meiocytes is the crucial question. This adult’s pollen mother cells (PMCs), or male meiocytes, were squashed and stained. Male meiosis was normal and no abortive pollen grains were observed. This female gametophytic apomict of a conifer, a dihaploid adult, is 100% homozygous yet also reproductively competent with normal male meiosis and functional male pollen. Here we show that doubled female gametophytes can produce embryos and reproductively competent adult trees. This shows a way to gain rapid homozygosity and produce completely inbred lines for larch. This is a novel breeding shortcut reported for the first time for a conifer species.

The production of high-quality planting material for the most commonly used woody species in urban greening is a complex challenge influenced by several factors. One of the key factors in seedling production, especially in pots, is the selection of an appropriate substrate. Testing various substrates for different species is an ongoing process. In Bosnia and Herzegovina, four of the most frequently used taxa for urban planting in the region were tested: two varieties of northern white-cedar (Thuja occidentalis L.), namely 'Smaragd' and 'Columna', as well as European boxwood (Buxus sempervirens L.) and Forsythia (Forsythia × intermedia). One-year-old rooted cuttings were transplanted into two-liter pots using five different substrates: plain soil, compost, lumbrico humus, peat, and a combination of all these substrates. At the end of the growing period, morphometric parameters of the seedlings were measured, and based on these measurements, quality indices were determined. The results showed that each species and variety responded differently to the various substrates. Generally, the best results for most of the taxa were obtained using locally produced lumbrico humus and compost. However, some seedlings, such as Thuja occidentalis 'Smaragd', exhibited similar growth characteristics across all substrates tested. Considering the varying costs of the substrates, it is possible to plan the production of these seedlings with significantly better quality while also reducing production costs.