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In Iceland and Denmark, there is an interest in planting Abies lasiocarpa for use as Christmas trees. To search for usable genetic material for both countries, 26 provenances of subalpine fir, covering most of its natural range, were planted in eastern Iceland and Jutland, Denmark. Flushing, bud set and survival rates were assessed. Artificial freezing of twigs, from field trials in eastern Iceland and Denmark, was done to rank the provenances for frost tolerance in the spring and autumn. The northernmost provenances showed earliest bud set, highest autumn frost tolerance and a latitudinal cline was delineated. Differences between provenances in flushing and spring frost tolerance were less than that found for bud set and autumn frost tolerance. The southernmost provenances showed earliest flushing and the most spring frost damage on buds. Mortality of single provenances in the field tests could not be attributed to low freezing tolerances in the autumn or spring. The southernmost provenances of Abies lasiocarpa from New Mexico and Arizona showed the highest survival rate in the field trial in East Iceland, while the eastern provenances showed a low survival rate except for two provenances from Utah and Wyoming. The western provenances from Washington state showed the best survival in Denmark, followed by the southernmost provenances. [ABSTRACT FROM AUTHOR]

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Over the last decade, the conversion of annual-rotation based crops or grassland areas into non-food perennial crops has been increasingly prevalent in European farming systems. This shift is associated with major changes in management practices and has created new environmental conditions and resources for wildlife. Impacts on birds have been examined for bioenergy agricultural systems, such as miscanthus plantations and short-rotation willow coppice. However, they remain largely unknown for Christmas tree plantations (CTPs) that have recently increased considerably in some European countries. We examined the extent to which CTPs alter bird species assemblages in the farmland areas of southern Belgium, where they mainly replace intensive grassland. The abundance of birds was recorded during the breeding season in randomly selected sites located in grassland and in CTP. Results show that introduction of CTP into landscapes dominated by grassland with low hedge densities locally increases bird species richness and abundance without leading to biotic homogenization. Differences in species richness and abundance between grassland and CTP decrease with increasing hedge densities. A community analysis indicates that the plantation of Christmas trees enriches the bird assemblage of intensive grassland areas. In intensive grassland with few hedges, small-size CTPs could constitute an option to increase structural heterogeneity and provide new potential breeding conditions for some farmland birds. However, questions remain about the genuine quality of the resources available in CTP and further research is needed to examine the breeding success and survival of birds that settle in this type of habitat. [ABSTRACT FROM AUTHOR]

Ten exoticAbiesspecies were tested in two field trials, where the aim was to find suitable species and provenances for Christmas tree production in coastal and fjord areas in Norway. The material included 14 provenances ofAbies nordmanniana, 3 provenances ofAbies bornmuelleriana, 3 provenances ofAbies koreana, 2 provenances ofAbies amabilis, and 1 provenance each ofAbies equi-trojani,Abies alba,Abies procera,Abies homolepis,Abies nephrolepis, andAbies forrestii. Field trials were established at Gulen in Sogn og Fjordane County and at Verdal in Nord-Trøndelag County. Christmas tree classification was done seven and eight growing seasons after establishment. The Christmas tree yield was higher in Gulen (64%) than in Verdal (45%), which is situated further north. Also, the survival and the height growth were higher in Gulen than in Verdal. A more humid climate and a longer growth season in Gulen may explain some of the differences. Of the 10 species,A. nordmanniana,A. homolepis, andA. bornmuellerianaproduced the highest Christmas tree yield at Gulen, whileA. homolepisandA. koreanahad the highest yield at Verdal. Due to early bud burst,A. equi-trojaniandA. bornmuellerianaare only suited for Christmas tree growing in the best climatic areas. [ABSTRACT FROM AUTHOR]

The article discusser the history, purpose and significance of maintaining accounts and records of incomes or capital gains and associated tax regulations through sale of Christmas trees by owners of Christmas tree farms, as prepared by the National Christmas Tree Association (NCTA).

Christmas tree production removes organic matter and associated nutrients from a site and can change soil physical properties, reduce mycorrhizal populations, and result in pesticide over-use/accumulation. These impacts have been implicated in potential field productivity declines. Assessing Christmas tree productivity is complicated by genetics, management, and market forces. We approached the perceived or possible productivity decline by examining soil properties on 22 pairs of sites. Each pair was comprised of an early rotation and late rotation plot with 1 and 3 or more rotations of Christmas trees, respectively. All sites were located on commercial Christmas tree plantations from the major production areas in Washington and Oregon. Chemical properties assessed to 45cm included pH, total C and N, and extractable P, K, Ca, and Mg. Soil physical properties assessed included aggregate stability and soil resistance. In general, we found little impact on soil resources that would impact long term production of Christmas trees. These impacts may have been mitigated by farmers following extension service recommendations. Nitrogen, K, and Ca appeared to be primarily affected by harvesting, but replacement by fertilizer application was probably adequate. [ABSTRACT FROM AUTHOR]

Phytophthora root rot of Fraser fir, caused by several Phytophthora spp., is a severe problem in Christmas tree production. Since fungicides are not economically viable for disease management in field plantings and host resistance is not available, cultural control methods were investigated. Mulches, dairy compost, and soil pH adjustment were tested at five field sites in North Carolina. Treatments included wood chips, wood chips plus compost, or pine bark as raised beds, and compost or sulfur tilled into soil. Soil and mulch microbial populations were characterized by dilution plating and calculation of a log series diversity index, and by enzyme analyses at 5, 12, 17, and 24 months after planting. Bacterial and fungal counts, microbial activity, and cellulase activity were higher in mulch than in soil at all sites and times (P < 0.01), and generally did not differ among mulch types or among soils. Treatments significantly affected disease ratings and tree survival at three of five sites, with one or more mulch treatments yielding lower disease ratings and greater survival than controls. Tree mortality at each time point varied significantly with cellulase activity in the upper root zone (P = 0.005). Other biological variables did not show significant relationships with disease ratings or mortality. [ABSTRACT FROM AUTHOR]