Introduced in 1750 as an ornamental tree and then in 1852 as a forest tree species, black locust occupied nowadays 250,000 ha in Romania. The tree species is important for its wood (lumber, poles, firewood, etc.), its honey-related production as well as its environmental role (afforestation of sand dunes and sterile dumps).

One of the most important activities in the middle basin of Jiu River is coal mining. After 1956 this activity has developed very quickly and two power plants were built in Rovinari and Turceni. As a result, sterile dumps and coal ash dumps have established so it was necessary to restore the area by afforestation. This activity started with the sterile dump Viaduct Rovinari, using Austrian pine and black locust, and continued with others such as Cocoreni and Moi. The most used tree species for ecological restoration was black locust. In order to express the stand structure, diameter at breast height (DBH), total height (H) and crown diameter were measured. The soil analysis were performed and showed differences in the content of heavy metals and radionuclides for both location. The study revealed positive correlations between DBH and H, a stronger one for Moi plantation. Our research highlights the capacity of black locust to establish and grow under very difficult site conditions.

The genus Callistemon belongs to the family Myrtaceae and comprises 34 species. They are woody aromatic trees or shrubs that are widely distributed in the wet tropics. According to the scientific literature, research on seed germination of this genus was rarely carried out. The germination requirements of Callistemon citrinus and Callistemon linearis were studied under controlled conditions in the laboratory. Seeds of both species were tested for germination at constant temperatures of 25°C, 30°C, 40°C, and at room temperature (23 ± 2°C) coupled with total darkness. Seeds were sown in Petri dishes (0.8% agar water) for 25 days of incubation. The kinetics of germination was determined according to four closely related parameters viz. final germination percentage (FGP), mean germination time (MGT), coefficient of velocity of germination (CVG) and time to 50% germination (T50). The room temperature of 23 ± 2 °C was found optimally suitable for both species, with 80% FGP and 11.1 days MGT for C. citrinus, and only 21.7% FGP and 12.4 days MGT were recorded for C. linearis. Furthermore, significant decrease in FGP was observed in both species at 25°C, 30°C and 40°C of temperature. The analysis also revealed that day 12-15 after seed sowing is suitable for final counts. Due of its very low FGP, seeds of C. linearis need an additional study to determine their viability.

The Dragon tree, Dracaena draco (L.) L., is an extremely threatened species. Its natural regeneration is disturbed and population appears to decrease rapidly. To design appropriate germination and seedling establishment protocols for a species conservation and restoration program, we studied the effects of pre-soaking, substrate and light availability treatment on seed germination for 15-day period. The condition for light availability corresponded to the sowing depth (at surface or at 2 cm depth). Germination occurred better in the dark when seeds were sown at 2 cm depth.  Our results showed that D. draco seeds sown in the sand under dark condition and after 24 hours pre-soaking in warm water germinated better and recorded 82.5% of final germination percentage (FGP). However, seedlings grew better in potting soil and recorded 54 mm of length. The maximum FGP of 51.3% was recorded under light condition. These results indicate that sowing depth and light availability could be a limiting factor for D. draco seed germination in natural condition. Furthermore, the establishment of D. draco seedlings (shoot and root length) during an 8-week period in pots was also assessed and illustrated. More research on seed ecophysiology is required to understand the mechanisms controlling seed germination of D. draco in arid and semi-arid conditions viz. salinity and drought.

Abstract In this study we investigated the dynamics of growth and quality features of 1+0 Austrian Pine (AP; Pinus nigra Arn.), Scots Pine (SP; Pinus sylvestris L.)  and Maritime Pine (MP; Pinus pinaster Aiton) seedlings in containers Yukosad (YS; hard plastic, 75cm3, 610 seedlings m-2) and Siset (SS; gray cardboard with white coating, 128 cm3, 589 seedlings m-2). The experiment, for all Pine species, was conducted in randomized blocks in four replications. Each replication contained 10 multipots of each container type. After the seed germination, every 15 days, i.e. 10 times during the vegetation season, 10 seedlings of each of 4 replications, i.e. 40 seedlings of each container and Pine species, were analyzed. The following morphological characteristics were measured: shoot height (SH), root collar diameter (RCD), shoot dry weight (SDW), number, length and dry weight (RDW) of I, II and III order lateral roots (FOLR, SOLR and TOLR) and of the central root. Quality ratios and indexes were calculated. The dynamics of growth of selected features during the vegetation season was expressed as trend lines. AP and SP seedlings, grown in containers YS had higher values of almost all measured traits (SH, RCD, SDW, number, length and dry weight of FOLR, SOLR and TOLR). However, in AP, the SS seedlings had better values of quality indexes and ratios (SQ, DQI, SDW/RDW and RDW/SDW ratio), than YS seedlings. SP seedlings, except for SQ, had better quality indexes in YS container. MP seedlings, with some exceptions, have better above ground quality features in SS containers, while root systems don’t differ significantly in both containers. Root quality indicators (root intensity and root bound indexes) are more favorable in SS containers in all Pine species. The polynomial trend lines in AP and SP grow in similar way and intensity in both containers, gradually increasing during the vegetation season. MP seedlings differ in much more intensive growth of above ground features, especially in the half of the vegetative period in both containers, while during this period root quantity and length stagnates. Generally, the quality of AP and SP seedlings is more or less equal and satisfactory in both containers, while MP seedlings show slightly better results in SS container.

Effects of harvesting residues (needle, bark and branch) on fresh and dry weights of two-year bare root seedlings originated from a seed stand and a seed orchard were examined in Brutian pine (Pinus brutia Ten.) to contribute nursery practices of the species and to estimate utilization possibility of the residues. Averages of seedling fresh and dry weights were 9.24 g and 3.36 g, respectively in polled treatments and origins. Results of analysis of variance showed significant differences (p≤0.05) among the treatments and between seed sources for the fresh and dry weights. Total averages of water content were 61.20% in root, 64.69% in stem and 63.75% in fresh weight of full seedling. Seed orchard seedlings had higher water content in root, stem and full seedling than seed stand seedlings opposite to fresh and dry weights. Averages of water content ranged from 60.39% (control treatment) to 65.94% (bark treatment) in full seedling of polled treatments and seed sources.

The tree of heaven Ailanthus altissima (Mill.) Swingle is a multipurpose tree in forestry. However, it is considered an invasive and dangerous plant for native species, and in particular for national parks, where many studies have recorded their involvement in the disturbance of the already developed floral diversity. Assessing the impact of certain abiotic conditions on this species may identify the expected areas to be colonized by its seed propagation. Germination of tree of heaven were tested for germination at constant temperatures of 25, 30, 40°C, and at room temperature varying from 25-30°C coupled with total darkness. Seeds were sown in Petri dishes (0.8% agar water) for 6 days of incubation. The kinetic of germination was determined according to five closely related parameters viz. final germination percentage (FGP), mean germination time (MGT), coefficient of velocity of germination (CVG), time to 50% germination (T50) and seedling length (SL). For the saline condition, the seeds underwent various NaCl concentrations from 0, 50, 100 or 200 mM. For each treatment, there were four replicates with 50 seeds incubated in a plastic container between two layers of moist sand at 15% of the appropriate treatment and then placed in a culture chamber at 27°C (± 2°C) for 30-day period. The effect of temperature was not significant on the MGT, CVG and T50. However, it was significant (p< 0.0001) on FGP and SL. The maximum germination of 94% was obtained at a temperature of 30°C and the lowest FGP of 40% was obtained at 25°C. For the salinity effect, the FGP of 75% in the control was much higher compared to the seeds treated at 50 mM NaCl with only 17.2% of FGP.  Germination was completely inhibited from 100 mM NaCl. A. altissima can be classified as sensitive to salt stress during seed germination and seedling emergence. The salinity effect then joined the temperature to monitor nature's A. altissima seed propagation.

Barren laterite lands are available plenty in Kasargode District of Kerala, India and being used mainly for extracting laterite bricks for building construction. These lands are found barren due to lack of vegetation and rocky nature. Afforestation in these lands is very essential to avoid extraction of laterite bricks so as to prevent degradation of lands.  To develop vegetation in these laterite lands the soil properties of laterite was examined as a first step of afforestation process.  It was found that the soils have lack of plant growth promoting microbes (PGPM) and poor in major nutrients (N, P, K). Therefore, the PGPM specifically arbuscular mycorrhizal fungi (Glomus fasciculatum and Glomus geosporum) and bacteria (Azospirillum brasilense and Bacillus megaterium) were used for afforestation in laterite lands along with Swietenia macrophylla G. King a commercially important tree of Kerala, India.  The laterite soils were collected and used as potting media for growing seedlings of S. macrophylla in nursery and the cultured PGPM were inoculated in to the seedlings of S. macrophylla and maintained for 3 months. The PGPM inoculated seedlings showed improved growth, biomass and nutrient uptake. Thereafter the seedlings were transplanted at laterite lands at Karmanthodi, Bovikanam, Kasargode, Kerala, India and monitored their growth for 12 months. The seedlings inoculated with PGPM showed up to 98% survival rate with improved growth. From this study it was understood that PGPM have the potential to increase the efficiency of plant growth system in S. macrophylla seedlings through supply of essential levels of N, P and K that helped for successful afforestation in hardy laterite lands.

Copper has been used by nursery managers for more than 100 years to suppress fungi and as a fertilizer for more than 50 years. Consequently, nursery seedlings with copper deficiencies are rare, especially for broadleaf species. In many nurseries, soil contains <10 μg-Cu g-1 and in greenhouse trials, pine seedlings are relatively tolerant of soil levels with 35 μg-Cu g-1. A million bareroot pine seedlings may contain 50 to 100 g-Cu and, when soil tests indicate low copper levels, managers might apply 1 kg-Cu per million seedlings. In contrast, it may take only 15 g-Cu to produce one million container-grown seedlings. Copper fertilization is typically not required when 30 cm of applied irrigation water contains 0.1 μg-Cu g-1 (supplying 0.3 kg-Cu ha-1). This review highlights some of the past and current uses of copper in bareroot and container nurseries with a focus on deficiency and toxicity effects as well as the impact of various copper-based products and provides recommendations on ideal soil and foliar ranges.

How pollen shapes forests and forestry can be illustrated using Siberia’s boreal forests which have historically produced some of the highest pollen concentrations in the Northern Hemisphere. Pollen’s contributions are categorized as follows: 1) forests and timber, 2) nontimber products and services and 3) emerging research at the forest-atmosphere interface. Examples are drawn from Pinus sylvestris (Scots pine), Pinus sibirica (Siberian stone pine) and Pinus koreansis (Korean pine). Pine pollen is not only vital to timber and nontimber products but it serves as a well-studied model system for atmospheric studies.