Reforesta

1-14

Authors: Fields-Johnson, C. W., Fike, J. H., Galbraith, J. M., Maguire, R. O., Day, S. D., Zedaker, S. M., Mathis, J. E.

Early growth and survival of tree seedlings is often poor on reclaimed coal surface mines in Appalachia. Biochar produced in bioenergy generation has potential for use as an amendment to improve seedling performance. Mine soil was collected from a recently reclaimed coal surface mine in Wise County, Virginia and mixed with loblolly pine (Pinus taeda L.) sawdust biochar, simulating application rates of 2.3, 11.2 and 22.5 Mg ha-1. Unplanted leaching columns and 4 L tree planting pots were filled with these biochar-soil mixtures, plus controls of pure mine soil and pure biochar. For the tree planting pots, additional pots were created where the biochar was applied as a topdressing at the same application rates as in the mixtures. One-year-old seedlings of both American sycamore (Platanus occidentalis L.) and black locust (Robinia pseudoacacia L.) were planted. Unplanted leaching columns were leached with collected rainwater for six months to simulate weathering. Trees were grown for one growing season. Black locust had higher average above-ground dry woody biomass (24.4 g) than American sycamore (17.0 g), and also higher below-ground biomass (61.0 g compared to 30.2 g). The pure biochar produced greater average below-ground biomass (99.9 g) than the pure mine soil (46.9 g). All of the biochar treatments produced greater average above-ground woody biomass (19.1 g – 33.4 g) than the pure mine soil (10.9 g). After weathering, biochar provided less available soil phosphorus, calcium and iron than the mine soil itself while increasing soil carbon and organic matter. High (22.5 Mg ha-1) biochar applications increased soil volumetric water holding capacity to 18.6% compared to 13.4% for pure mine soil. Naturally-occurring herbaceous biomass in the pots was negatively correlated with above-ground woody biomass at r = -0.483. Topdressing and full incorporation of biochar were not significantly different in their effects on biomass. Results suggest that pine biochar either broadcast at 2.3 - 22.5 Mg ha‑1, or mixed in planting holes with backfill soil, will promote faster above-ground growth and larger root systems in seedlings in mine soils. Further studies should test these methods in the field over multiple years and further refine recommendations of the rate of biochar to use and how best to apply it. New systems are being developed in Appalachia to produce biofuels and biochar from local biomass and to recycle biochar into the land base to enhance future biomass productivity. Applying 4 L of biochar mixed with the backfill of newly-planted trees is the top recommended practice for tree performance.

31-40

Authors: Nicolescu, V. N., Hernea, C., Sandi, V.

The paper focuses on the use of alley cropping, an arable agroforestry system comprising rows of trees planted with a companion crop grown in the alleyways between the rows, in two sub-compartments (81B%: 0.75 ha, elevation 715 m asl; 81E: 3.4 ha, elevation 735 m asl) artificially regenerated at 1.80 m x 1.60 m spacing in the south-east of Transylvania (Romania) in 1997 (81B%) and 2003 (81E). The climate (Dfbx, specific to low and middle mountains) and soil (luvisol, of moderate fertility for pure or mixed Quercus petraea stands) are only moderately favourable to strawberry culture. The rows of tree species consists of Quercus rubra, Acer pseudoplatanus, Prunus avium (81B%), and Quercus petraea, Fagus sylvatica, Acer pseudoplatanus, and Larix decidua (81E). Strawberries (variety Elsanta,) were planted at 60 x 60 cm spacing in two pure rows in-between the tree rows as well as within the rows of planted trees. Both plantations were fenced, with manual topsoil hoeing up to four times a year, lighly fertilized (N, P, K complex) and chemically protected against browsing and pests. Strawberry rotation (six years, of which five years - two to six - with fruit production) was longer than the one (maximum three years) recommended in pure crops. Strawberry production reached the maximum level in years 3 or 4. Under the local conditions, the alley cropping with strawberries had demonstrated to be a viable alternative to the 'classical' monocropping system in terms of (a) survival rate of plants (over 95 per cent), (b) initial height growth of plants (very quick, resulting from reduced competition with grasses and naturally regenerated forest trees such as pioneer species), (c) establishment of a new forest culture, the full forest cover being achieved immediately after the end of strawberry production, as well as (d) economics (early and relevant revenue from the crop).

60-70

Authors: Thiffault, N., Ward, C.

Stock types used in reforestation projects can influence plantation success, as they determine the morphological attributes of the planted seedlings. They can also interact with silviculture treatments to influence early seedling survival and growth. As nurseries develop and produce new stock types in response to –and in interaction with– manager needs, research efforts must be pursued to validate early seedling performance and long-term growth and yields. In this context, we aimed to evaluate the main and interactive effects of mechanical site preparation and stock type on planted black (Picea mariana [Mill.] BSP) and white spruce (P. glauca [Moench.] Voss) seedling dimensions at 16-y, and estimate the long-term impact of stock type on the merchantable volume at rotation age for white spruce. We hence compared medium (200 cm3 root plug) and large (350 cm3 root plug) containerized seedlings, as well as large bare-root seedlings of both species, in a field experiment established in Quebec (Canada), where there is a ban on the use of chemical herbicides for vegetation management treatments. Our results confirm that there is a significant, although limited impact of stock type on the size of black and white spruce at the juvenile stage, when medium and large stock types are compared, but that these small differences have a negligible effect on the estimated merchantable volume produced at rotation age (60 years). Mechanical site preparation does not promote seedling growth on these rich sites with thin humus. Therefore, selection of a medium or larger stock type for reforestation projects and application of mechanical site preparation in ecosystems similar to the one studied here should be based on other considerations than growth and yield, such as seedling availability, production and planting costs, or operational constraints.

86-99

Authors: Ndiaye, O., Goudiaby, A. O. K., Sambou, A.

Despite the importance of forests and trees, Senegal is facing to the loss of forests and the decline of tree diversity and density. This study focuses on Moringa oleifera Lam., Acacia mellifera (Vahl) Benth. and Zizyphus mauritiana Lam. which constitute a significant source of food and economic value for the populations of Casamance.In addition to a germination test, a follow-up of seedlings on different substrates was carried out in the nursery, in order to determine the effect of substrates on some growth parameters (number of leaves, height, diameter and biomass).The substrates used were three potting mixtures of forest soil of Faidherbia albida (FSFA), Elaeis guineensis (FSEG) and Anacardium occidentale (FSAO) and sand with the following proportion: 1/3 sand + 2/3 forest soil). Based on species, the germination rate was higher for A. mellifera (84%) followed by M.oleifera (55%) and Z. mauritiana (50%). The germination rate was more important in FSFA and FSEG than in FSAO. For growth parameters, there was a significant effect (P<0.05) of substrate type on height, diameter, number of leaves and root biomass. In term of growth parameters, the seedling performed better in FSFA and FSEG than in FSAO. The species effect was also significant (P<0.05) with higher root biomass and diameter found in M. oleifera and height and number of leaves in A. mellifera. The most important total biomass was found in FSFA followed by FSEG. Comparing the fraction of biomass according to the part of the seedling, the stem and branch had the higher fraction of biomass for A. mellifera (43%) and M. oleifera (38%) and the leaves for Z. mauritiana (46%).However, thetype of substrate can affect seedling development and growth parameters and the better results were recorded in FSFA and FSEG substrates.

110-139

Authors: Steven Grossnickle

Seedling field performance is affected by both their quality and reforestation site conditions. Seedlings enter the establishment phase when they start to develop root systems into the surrounding soil and are coupled to the restoration site. Once seedlings are established, their inherent growth potential is related to morphological and physiological attributes and their ecophysiological response to site environmental conditions, which ultimately determines field performance. This establishment phase is a time when seedlings developed with certain nursery cultural practices begin to respond to site conditions. This phase is also a period when silvicultural practices have created microsites intended to benefit established seedlings field performance. Seedlings can be exposed to a wide range of environmental conditions during the establishment phase, some of which may be extreme enough to exceed their ability to physiologically tolerate environmental stress. When this occurs, seedling growth on the restoration site is reduced. On the other hand, this phase can provide planted seedlings with ideal environmental conditions that allow for an optimum physiological response and maximization of their growth potential. An understanding of the ecophysiological capability of planted seedlings can ensure they have the best chance at rapid stand establishment.

1-3

Authors: Vladan Ivetić

The conference on "Reforestation Challenges" took place on 20-22 June 2018 in Belgrade, Serbia, at Faculty of Forestry of the University of Belgrade. This was the fourth meeting on reforestation challenges, after three successful meetings in three previous years (2015 – Belgrade, Serbia; 2016 – Krakow, Poland; 2017 – Session at the IUFRO Congress in Freiburg, Germany). This Conference, like the first one, was organized by Faculty of Forestry of the University of Belgrade, IUFRO (specifically by IUFRO Unit: 3.02.00 - Stand Establishment and Treatment), and Reforesta Scientific and professional Society.

15-21

Authors: Kerkez, I., Nonić, M., Devetaković, J., Šijačić-Nikolić, M., Ivetić, V.

Aiming to produce forest reproductive material at the family level, we tested quality of twenty Fraxinus angustifolia Vahl half-sib lines in the nursery experiment. We measured height (HT) and root collar diameter (DIA) of one-year old seedlings, and we monitored germination rate and mortality during the first growing season. Seeds of 20 half-sib lines originating from Sombor area (north Serbia) were sown in seedbed on autumn 2016. The seed dormancy was not broken in all seeds equally, resulting with un-uniform germination over a two months period. All measured attributes shows a statistically significant differences, indicating a strong effect of genetic control. The highest average and DIA were measured in half-sib line 7 (22.62 cm; 5.79 mm, respectively). The lowest average DIA was measured in half-sib lines 18 (2.85 mm) and 19 (2.94 mm), which can be result of growing density effect (104 seedlings m-2 for line 18 and 126 seedlings m-2 for line 19, compared to 40 seedlings m-2 for line 7). The correlation between DIA and HT is strong and positive (R=0.90). Due to its morphological superiority, half-sib line 7 could be recommended for mass production of Fraxinus angustifolia seedlings at the family level.

27-32

Authors: Ivetić, V., Kerkez, I., Denić, I., Devetaković, J.

Beech is the most important tree species in forests of Serbia. However, despite its significance, the taxonomic status of beech in Serbia is unclear. Morphology of the cupules can be successfully used to distinguish species and within species taxa. In this paper we report results on cupules morphology, measuring the same attributes reported by Mišić (1955): 1) Length of the longest valve of cupule, 2) Width of that valve (at widest point), 3) Distance between base of the longest valve and peduncle, 4) Length of cupule without peduncle, and 5) Length of peduncle. The length of cupule and peduncle length from 12 populations in Serbia are in the range reported for Fagus sylvaticain Serbia and western Eurasia. Results of cluster analysis shows a grouping of populations in two groups:1) the southeast group, and 2) group consist of populations from northwest, east and southeast of Serbia. Populations from this southeast group also consist the group of populations on altitude over 850 m, indicating presence of ecotypes. The exception is population from Stara Planina (1,520 m a.s.l.) which is grouped with populations from altitudes under 850 m.

54-76

Authors: David B. South

In North America, most tree nursery nutrition publications during the past two decades involved either container-grown stock or stock grown in greenhouses. In contrast, most bareroot nursery fertility trials in North America were published during the last century. As a result, some bareroot fertilization recommendations have remained the same since 1980 and some practices continue to be based on myths and assumptions. The bareroot nursery industry in the USA might benefit if the next generation of graduate students will consider testing old and new theories about nursery fertilization. Hopefully, they will discover new facts so that future fertilization regimes will be based on science. This paper provides various fertilizer trials that should be established in bareroot nurseries.

1-11

Authors: Augustin KN Aoudji, Caroline Séhouéto, Anselme Adégbidi, Rodrigue S Kaki, Jean C Ganglo

The viability of Acacia auriculiformis production system in southern Benin was studied from an analytical perspective combining the production techniques and the financial profitability. The driving research question was as follows: “Will the nurseries be able to supply the seedlings suited to successful reforestation programmes?”. A survey was carried out among nursery holders in the Atlantique Department. The snowball sampling method enabled the survey of 55 nursery holders, based on semi-structured interviews. Respondents provided data on the organisation of production, production techniques, production costs, and sales revenues. There were two types of nurseries: individual nurseries and group nurseries. The stages of acacia seedlings production were as follows: seed collection, dormancy breaking, sowing, and tending of young seedlings. Overall, the production techniques used by nursery holders were effective. The net revenue for 1000 seedlings ranged between XOF 9000 and 26000. Group nurseries had lower production costs, hence higher revenues, compared to individual nurseries. It is essential to assist nursery holders through capacity strengthening training and the provision of good quality seeds.

21-26

Authors: Jovana Devetaković, Zoran Maksimović, Boris Ivanović, Zvonimir Baković, Vladan Ivetić

Austrian pine (Pinus nigra Arnold) seedlings are one of the most produced planting material in Serbian nurseries. In this study we compared a field performance of two container stocktypes, one usually used (2+0 produced in Plantagrah I) and one recently introduced (1+0 produced in Hiko V120 SS). The trial was established at planting site Vlaško polje (East Serbia), at altitude of 840 m a.s.l., one year following the total destruction of previous pine plantation by ice. One-year-old Austrian pine seedlings produced in Hiko containers show similar initial height and root collar diameter at planting time as two-year-old seedlings produced in traditionally used Plantagrah I containers. There was no vegetation control at field trial during the first growing season. At the end of the first growing season, taller (15.6 cm) and more slender (H/D=4.5) 1+0 seedlings from Hiko containers survived at higher rate, and shorter (10.9 cm) and more stocky seedlings 2+0 produced in Plantagrah I grow in height at higher rate. Seedlings taller at the planting time kept their advantage in size after the first growing season at the field. We found that both stocktypes can be used in operational planting programs on sites with lack of vegetation control.

54-68

Authors: Ciprian Palaghianu, Ioan Dutca

Preserving forest legacy was an important objective throughout Romanian history and so is today. Artificial forest regeneration (including both reforestation and afforestation) was widely used to ensure the forest continuity, following forest harvesting, or to create new forests on non-forest lands. As Romania has undergone various political changes that affected the socio-economic environment, these changes also left significant marks on forest cover dynamics. In this paper, we chronologically present the historical initiatives to preserve and increase forest cover in Romania, the current practices, available funding and future perspectives on artificial forest regeneration. Increasing forest cover from the current level of 27% to, and beyond European average of 33% seems an ambitious target for Romania. However, that may be achievable if the sources of funding for afforestation would diversify and increase, the available funds would be more effectively accessed, national forestry regulations would be less bureaucratic and the guidelines on artificial forest regeneration would be up to date and less restrictive. The whole framework of forestation should be revised to comply with recent social, economic and environmental realities, and modern criteria and indicators for sustainable forest management should be explicitly included. The new goals should also be tailored to the changes regarding the property type, climate related trends and new requirements of the forest certification systems.

94-142

Authors: Steven C Grossnickle, Vladan Ivetić

Direct seeding has been considered a forest restoration option for centuries. Over the past half century, the use of this practice has declined in developed countries as forest regeneration programs have advanced with the production of quality seedlings that can successfully establish restoration sites. Direct seeding is being reconsidered as a restoration option as the potential size of the worldwide forest restoration program has grown because of massive deforestation in third-world nations and due to global climate change. This review examines direct seeding from a number of perspectives. First, merits of using this practice in restoration programs are defined. Major merits of this option are that it can be done quickly, over hard to reach and large disturbed areas, and at a relatively low cost. Second, current research findings from restoration programs are discussed. The major finding is that seedling establishment rates are low (i.e. typically around 20% of seeds planted) due to site conditions, seed predation and vegetation competition, and field performance (i.e. survival and growth) is lower than planted seedlings. Third, operational practices for the application in restoration programs are reviewed. To successfully conduct direct seeding programs practitioners need to consider seedbed receptivity, seed distribution and seeding rate. Fourth, potential new practices are presented. Some of these new practices attempt to create a more effective means to disperse seed across the site, minimize seed predation or create a more favorable microsite environment. This review provides a synthesis of what is known about direct seeding, thereby allowing practitioners to make a rational decision of whether to apply this practice towards their forest restoration program.