Precise tree-ring dating of building activities despite the absence of bark: A case-study on medieval church roofs in Damme,Belgium

A detailed dendrochronological survey was performed on the medieval roofs of the Church of Our Lady (CoOL) in Damme, Belgium. Seen its complex architectural history, special attention was paid to the identification of consecutive building phases, based on combined architectural historical research and tree-ring dating. In total 64 increment cores were taken throughout the roof structures of the CoOL. All roof timbers are made of European oak (Quercus robur/petraea), of which only few have surviving sapwood or bark. Tree-ring dating confirms the late 13th/early 14th century construction date of the roofs. For all chronologies that were composed, the highest correlation values are found with reference chronologies covering the catchment area of the river Meuse. From the dating results of the timbers of the CoOL it becomes clear that the same timber source was used for nearly a century. On several of the examined roof timbers, rafting joints were observed, demonstrating that the timbers were indeed tied together as a raft and floated down the river.By implementing sapwood estimates in a Bayesian chronological model (OxCal), tree-ring series with surviving sapwood from coeval roof structures were combined in order to narrow down the time range for the felling date. Based on the refined interpretation of the felling dates, several consecutive building phases can now be identified and dated, leading to a new interpretation of the architectural history of the CoOL. Intriguingly, a marked interruption in building activities is observed around 1300. Probably this is related to the instable political situation at that time, caused by the armed conflict that emerged between the Count of Flanders and the king of France. Since Damme served as the outport of the riotous city of Bruges, it was alternately seized by the French and Flemish, both consuming considerable amounts of timber and other building materials for military fortifications. Potentially this led to a shortage in building materials and provoked a stop in building activities.This paper demonstrates the power of Bayesian models to refine the interpretation of dendrochronological dates in architectural analyses of medieval historical buildings.     

The ups and downs of the building trade in a medieval city: Tree-ring data as proxies for economic,social and demographic dynamics in Bruges (c. 1200–1500)

The exceptional preservation of the cityscape in the medieval city of Bruges (Belgium) triggered dendrochronological research on numerous preserved roof constructions in historical buildings, that date from the Middle Ages up to the early modern period. As many of these oak timbers lack the preservation of waney edge, a method was developed to combine sapwood estimates of felling dates within each building phase and to compute a summed probability distribution (SPD) for those felling dates. These summed probabilities now allow us to reconstruct temporal trends in building trade activity in an expanding medieval city. When linked to the social status of the patrons of the building projects, it is observed that resilience to demographic crisis and political turmoil differs among the social groups and political elite of a medieval society. Furthermore the dating results of decades of tree-ring research now provide a typo-chronological framework of roof constructions and shows that it took nearly two centuries before more advanced technological skill in the construction of roofs completely replaced the traditional common rafter roofs.     

Dendroprovenancing: A preliminary assessment of potential to geo-locate kauri timbers in northern New Zealand

After 1840, New Zealand kauri (Agathis australis) became the focus of a large-scale timber industry in the upper North Island, which converted trees into timber that was then used in construction. Cities such as Auckland and Wellington relied on importing kauri to meet local demand for construction and other uses. Kauri timbers from buildings and in-ground features, mostly in Auckland city, have been collected for tree-dating and master chronology development. Although the use of timber at archaeological sites is understood, the geographic origin of the timber from within the natural range of kauri (north of 38 °S) is largely unknown. This limits interpretation of archaeological wood and constrains use of the tree-ring data in dendroclimatology. In this paper, we consider the potential to provenance kauri timbers used in 19^th and early 20^th century New Zealand buildings, using a combination of documentary sources, t-value mapping, and refined statistical matching using spatial patterns of correlations. Analysis of documentary sources for a test period of 1861–1865 CE indicates that there is sufficient information about the kauri timber industry to provide a geographic context for provenancing kauri in the upper North Island. The use of t-values for provenancing may be confounded by the relatively small size of the kauri growth region and a lack of sufficient spatial differentiation in growth patterns between the sub-regions. However, a new approach of using indexed residual chronologies and field correlations has promise for geo-locating timber in a relatively small region. The research highlights the value of establishing kauri provenance to New Zealand dendroclimatology, dendroarchaeology and environmental history.     

Reconstructing the oaks’ growth patterns in Greece with the use of historical timber: Case studies from Western Peloponnese

Southern Greece is a region where available oak reference chronologies are still missing, making dendroarchaeology and dating of historical buildings rather challenging, if not impossible. In the current study we performed wood identification and dendroarchaeological analysis on timber from three historical buildings: the castles of Androusa and Koroni and the Church of Agios Dimitrios, in Western Peloponnese. The three monuments represent buildings of different uses covering different periods, but also sharing a common characteristic: oak was the only timber used in their construction, while the number of preserved timber elements is very limited. A dendroarchaeological examination of these three historical buildings, together with radiocarbon and wiggle-matching analysis, provided valuable chronological information for the local archaeologists, historians, and other scientists. Application of dendrochronological techniques has helped place the three buildings under study into the Ottoman period. Our results also show that timber was acquired most probably from local non-managed forests, which suggests that oak forests were present in the broader area at least from the late 15th to the first half of the 18th centuries. The discordance between dendrochronological and radiocarbon dates in one of the three cases highlights the need for further exploration of the study area through a combined implementation of both dendrochronological and radiocarbon dating analyses in order to develop well-replicated local oak chronologies. Our study also shows that dendroarchaeology can contribute significantly to the cultural and landscape history of Western Peloponnese even with an examination of limited number of preserved timber elements from historical buildings.     

Dating furniture and coopered vessels without waney edge – Reconstructing historical wood-working in Austria with the help of dendrochronology

In the present study, 208 furniture and 168 coopered vessels from three Austrian museums were examined. Dendrochronology was used to date objects and to extract further information such as the necessary time for seasoning, wood loss through wood-working and methods of construction. In most cases sampling was done by sanding the cross section and making digital photographs using a picture frame and measuring digitally.The dendrochronological dates of the sampled furniture range between 1524 and 1937. The group of furniture includes cupboards, chests, tables, benches, commodes and beds. In many cases furniture was artfully painted and sometimes even shows a painted year. With the help of dendrochronology it was proved that some objects had been painted for some time after construction, or had been over-painted. Most furniture, however, was painted immediately after completion. In this case, the seasoning and storage time of the boards and the wood loss due to shaping can be verified. As an average value, 14 years have passed between the dendrochronological date of the outermost ring and the painting. The time span includes time of seasoning and storage and the rings lost by wood-working. This leads, on the one hand to a short storage time of less than 10 years and on the other hand to very little wood loss due to manufacturing. Those boards being less shaped turned out to be back panels of cupboards, therefore they are recommended to be sampled for dating.Coopered vessels were dated between 1612 and 1940. There was evidence that staves were split and not sawn in many cases. The staves were often split out of the outermost part of the tree and hardly any wood was worked away which was proved by the close dendrochronological dates of the single staves of a vessel.Since there is a short time of storage and only little wood loss through wood-working, dating of objects without a waney edge becomes reasonable.     

Latest developments of dendro-archaeology in the French Alps: Assessing changes in mountain forests exploitation over the last millennium

Dendrochronological studies are carried out on rural buildings in the French Alps for twenty years. In this contribution, we examine an extensive dataset of larch timbers (n = 1294) that were dendrochronologicaly dated at 139 buildings. This material yielded felling dates spanning the 11th century to the 20th century and contributed to improve our knowledge of human occupation and exploitation of mountain forests during the second millennium CE. From the 11th to the 14th century, rural populations increasingly exploited older forests. The crises of the 14th century led to a significant decrease in construction and by extension in tree cutting. The beginning of the 15th century marks a resumption of construction and felling which is continuous until the beginning of the 20th century. There is a relationship between the age of harvested trees, the number of dates and population fluctuations, which corroborates findings at the European scale. Regional trade probably influenced the stem diameters used in constructions in the immediate vicinity of the forests. Logging regulations can be perceived through variations in the age of harvested trees. The 14th century gap in felling dates would also mark a transition period in the exploitation of mountain forests and by extension a transformation of the economy.     

Oxygen isotope dendrochronology of Llwyn Celyn; One of the oldest houses in Wales

We report the application of oxygen isotope dendrochronology to date a high-status and remarkably unaltered late medieval hall house on the eastern border of South Wales. The oak timbers have either short and complacent ring series, or very strong growth disturbance, and none were suitable for ring-width dendrochronology. By using stable oxygen isotopes from the latewood cellulose, rather than ring widths, it was possible to cross-match and date all 14 timber samples and to provide felling dates related to several phases of building. The hall and solar cross-wing were constructed shortly after 1420CE, which is remarkably early. The house was upgraded using timbers felled in the winter of 1695/6CE by ceiling over of the hall and inserting a chimney. A separate small domestic building was added at the same time and the addition of the kitchen is likely to be contemporaneous. A substantial beast house was added a few years before the house was refurbished, emphasising the importance of cattle as the main source of wealth. A small barn with timbers felled in spring 1843 CE was added later. Llwyn Celyn is one of the most important domestic buildings in Wales, but without the new approach none of the phases of its evolution could have been dated precisely. Oxygen isotope dendrochronology has enormous potential for dating timbers that have small numbers of rings and/or show severe growth disturbance and it works well in regions where tree growth is not strongly constrained by climate. The research was generously supported by the Leverhulme Trust, Natural Environment Research Council, Landmark Trust and the UK National Lottery Heritage Fund.     

Long-term Coordination of Timber Production and Consumption Using a Dynamic Material and Energy Flow Analysis

A dynamic model for wood and energy flows is used to analyze regional timber management. The model combines a sitequality-dependent forest-growth module with modules for the timber industry, timber products use, waste management, and energy supply. The model is calibrated with data of a Swiss lowland region for the period of 1900–1997. Scenarios are developed for the period until 2100 in order to discuss possible future roles of domestic timber.
Model simulations show that, with present strategies, timber overproduction will further increase in the twenty-first century because of an increase in forest site quality in the second half of the twentieth century, among other reasons. The increase in building gross floor area of the region by a factor of 5 during the twentieth century coincides with a reduction of timber use in building construction by a factor of 4.5, from 90 kg/m2 to 20 kg/m2. Increasing timber density in buildings could address overproduction; however, a strategy of timber construction could not be accomplished with domestic timber alone. A balance of production and consumption on the present level could also be achieved in a scenario in which the present building stock is gradually exchanged during the twenty-first century with buildings that exclusively use a combination of solar panels on roofs and domestic firewood and used wood as heat-energy sources. These replacement buildings would have density typical of late twentieth-century buildings, and they would need to perform on a low-energy standard of not more than 130 MJ/m2/yr.     

Dendrochronological analysis of an English chest: Contributing to knowledge about wood supply and chest production in 16th century England

Historic furniture has a great ethnographic and historical value, as styles and designs responded to specific uses, fashion trends and the social status of the buyer or the commissioner. Placing it in an exact chronological and geographical production context increases our knowledge about preferences for materials, designs, and woodworking practices for household commodities. Here we present the results of dendrochronological research carried out on an English chest from a private collection. The chest is of a hybrid construction, with boarded sides and back, and a joined front with four carved linenfold panels. It had been described as made of Baltic oak and dating to the mid-16th century, a crucial transition period for which only a few early chests have been analysed. Our results demonstrate, however, that the wood from the lid, side boards and back originates from the south of England. Heartwood/sapwood border in the left side board has allowed an estimated felling date for the tree of between 1520 and 1552. Terminus post quem dates of the rest of the elements pre-dating this interval indicate that the chest was likely made in the second quarter of the 16th century, as initially described. Three linenfold panels show typical features of Baltic wood, whereas the fourth one has different characteristics and could have been made with English oak, but the lack of access to the tree-ring patterns hampers verifying this hypothesis. Mixture of provenances suggests a production workshop in London, although other town in the south with a major timber market cannot be discarded. The construction features are described, and two distinct marks found in the chest are discussed in the regional context of its production. To allow the compilation and inventory of such marks, the ‘Marks on Wood’ community has been created in Zenodo and is presented here.     

Potential Energy Wood Production with Implications to Timber Recovery and Carbon Stocks Under Varying Thinning and Climate Scenarios in Finland

An ecosystem model (Sima) was used to investigate the impact of climate and varying thinning regimes concurrently on energy wood and timber production as well as on growth and carbon stocks during 2010–2099 in southern (below 64° N) and northern (above 64° N) Finland. The analysis was carried out using sample plots from the ninth National Forest Inventory. According to the results, both energy wood and timber production increased under the changing climate, with this effect being found to be higher in northern compared to southern Finland. In relative terms, the effect of forest structure, however, was more pronounced than that of climate, especially in southern Finland. Increased basal area thinning thresholds enhanced carbon stocks compared with current thinning regime. In addition, increased thinning thresholds enhanced concurrently energy wood production (at final felling) and timber production during the period 2040–2069 and merely energy wood production (at final felling) during 2070–2099. In absolute terms, the production potential of energy wood at energy wood thinning was found to be higher in northern compared with southern Finland, but the case was opposite at final felling both in current and changing climate. It was concluded that a concurrent increase in energy wood and timber production as well as carbon stocks would be possible in Finnish forests if thinning was performed at a higher tree stocking level than in the current recommendations.     

Buildings and wood trade in Aix-en-Provence (South of France) during the Modern period

Many buildings are being restored in the city of Aix-en-Provence, southeastern France and allowed systematic dendrochronological analyses. 144 fir timbers (Abies alba Mill.) were examined and dated between 1303 and 1933. They highlight three felling phases (Medieval period, 17th-18th century, and 19th century). The best documented one corresponds to the 17th-18th centuries and coincides with significant building activity connected to the status of Aix, which is the parliamentary capital of Provence. Around Aix-en-Provence, it is difficult to find timbers with good dimensions. Our results show that timbers were transported from the Alps to Aix’s buildings. Potential testimonies of this timber trade have been found, such as raft assemblage marks, and carved signs and letters. A dendroprovenancing case study shows that between 1810 and 1890, some of Aix’s timbers could have come from the Northern French Alps or the Verdon-Durance region. Finally, the lack of timbers with good dimension and the difficulties of timber supply contributed to the development of reuse economy and technical innovation. These results are the foundation of a future well-established dendroprovenancing approach in the Southern Alps.     

The Growth of Urban Building Stock: Unintended Lock‐in and Embedded Environmental Effects

Building stocks constitute enduring components of urban infrastructure systems, but little research exists on their residence time or changing environmental impacts. Using Los Angeles County, California, as a case study, a framework is developed for assessing the changes of building stocks in cities (i.e., a generalizable framework for estimating the construction and deconstruction rates), the residence time of buildings and their materials, and the associated embedded environmental impacts. In Los Angeles, previous land‐use decisions prove not easily reversible, and past building stock investments may continue to constrain the energy performance of buildings. The average age of the building stock has increased steadily since 1920 and more rapidly after the post–World War II construction surge in the 1950s. Buildings will likely endure for 60 years or longer, making this infrastructure a quasi‐permanent investment. The long residence time, combined with the physical limitations on outward growth, suggest that the Los Angeles building stock is unlikely to have substantial spatial expansion in the future. The construction of buildings requires a continuous investment in material, monetary, and energetic resources, resulting in environmental impacts. The long residence time of structures implies a commitment to use and maintain the infrastructure, potentially creating barriers to an urban area's ability to improve energy efficiency. The immotility of buildings, coupled with future environmental goals, indicates that urban areas will be best positioned by instituting strategies that ensure reductions in life cycle (construction, use, and demolition) environmental impacts.     

Greenhouse gas emissions from forestry in East Norway

Purpose

So far no calculations have been made for greenhouse gas (GHG) emissions from forestry in East Norway. This region stands for 80 % of the Norwegian timber production. The aim of this study was to assess the annual GHG emissions of Norwegian forestry in the eastern parts of the country from seed production to final felling and transport of timber to sawmill and wood processing industry (cradle-to-gate inventory), based on specific Norwegian data.

Methods

The life cycle inventory was conducted with SimaPro applying primary and secondary data from Norwegian forestry. GHG emissions of fossil-related inputs from the technosphere were calculated for the functional unit of 1 m³ timber extracted and delivered to industry gate in East Norway in 2010. The analysis includes seed and seedling production, silvicultural operations, forest road construction and upgrading, thinning, final felling, timber forwarding and timber transport on road and rail from the forest to the industry. Norwegian time studies of forestry machines and operations were used to calculate efficiency, fuel consumption and transport distances. Due to the lack of specific Norwegian data in Ecoinvent, we designed and constructed unit processes based on primary and secondary data from forestry in East Norway.

Results and discussion

GHG emissions from forestry in East Norway amounted to 17.893 kg CO₂-equivalents per m³ of timber delivered to industry gate in 2010. Road transport of timber accounted for almost half of the total GHG emissions, final felling and forwarding for nearly one third of the GHG emissions. Due to longer road transport distances, pulpwood had higher impact on the climate change category than saw timber. The construction of forest roads had the highest impact on the natural land transformation category. The net CO₂ emissions of fossil CO₂ corresponded to 2.3 % of the CO₂ sequestered by 1 m³ of growing forest trees and were compared to a calculation of biogenic CO₂ release from the forest floor as a direct consequence of harvesting.

Conclusions

Shorter forwarding and road transport distances, increased logging truck size and higher proportion of railway transport may result in lower emissions per volume of transported timber. A life cycle assessment of forestry may also consider impacts on environmental categories other than climate change. Biogenic CO₂ emissions from the soil may be up to 10 times higher than the fossil-related emissions, at least in a short-term perspective, and are highly dependent on stand rotation length.     

Castle Pišece,Slovenia – Building history and wood economy revealed by dendrochronology,dendroprovenancing and historical sources

Castle Pišece, located in SE Slovenia near the border with Croatia, is thought to have been built in the 12th/13th century as one in the line of Salzburg fortresses on the then SE border of the Holy Roman Empire. During thorough restoration that started in 2005, its wooden constructions became accessible for dendrochronological investigations. We collected representative samples from floor or ceiling constructions in most of the rooms in the castle. Dendrochronology helped us to identify felling dates of wood and to propose probable years of reconstructions in 1515, 1578, 1644, 1697, 1752, 1758, 1775 and 1878. The dating showed that the constructions in the presumed Romanesque and Renaissance parts of the building were not as old as expected, whereas those in the supposedly Baroque part of the castle were older than assumed. The selection of wood species used for constructions varied over time. Constructions with end dates 1515–1697 were made of oak (Quercus petraea and Q. robur), those dated to 1752 of silver fir (Abies alba), those dated to 1758 of sweet chestnut (Castanea sativa) and those dated to 1878 of common beech (Fagus sylvatica). Comparison of forestry archives and vegetation in the area showed that most of the timber could have originated from nearby forests; only silver fir had to be transported from sites that were at least 20 km away from the castle. Cross-dating of tree-ring series of oak elements with two reference chronologies from Slovenia and two from Austria confirmed the great likelihood that the wood used mostly originated from Slovenia. This indicates that dendroprovenancing, not used in the area before, could also be used SE of the Alps. Both the existing archival documents and dendrochronology indicate that woodworks have taken place every few decades in some periods. The dendrochronological dates can be partly linked to reports on earthquakes (especially the devastating one in 1511), rebellions and year marks carved on the stone plaques.     

Quantifying the greenhouse benefits of the use of wood products in two popular house designs in Sydney, Australia

Purpose

As the average wood products usage per unit of floor area in Australia has decreased significantly over time, there is potential for increased greenhouse gas (GHG) mitigation benefits through an increased use of wood products in buildings. This study determined the GHG outcomes of the extraction, manufacture, transport, use in construction, maintenance and disposal of wood products and other building materials for two popular house designs in Sydney, Australia.

Methods

The life cycle assessment (LCA) was undertaken using the computer model SimaPro 7.1, with the functional unit being the supply of base building elements for domestic houses in Sydney and its subsequent use over a 50-year period. The key data libraries used were the Australian Life Cycle Inventory library, the ecoinvent library (with data adapted to Australian circumstances where appropriate) and data for timber production from an Australian study for a range of Australian forestry production systems and wood products. Two construction variations were assessed: the original intended construction, and a “timber-maximised” alternative. The indicator assessed was global warming, as the focus was on GHG emissions, and the effect of timber production, use and disposal on the fate of carbon.

Results and discussion

The timber maximised design resulted in approximately half the GHG emissions associated with the base designs. The sub-floor had the largest greenhouse impact due to the concrete components, followed by the walls due to the usage of bricks. The use of a “timber maximised” design offset between 23 and 25 % of the total operational energy of the houses. Inclusion of carbon storage in landfill made a very significant difference to GHG outcomes, equivalent to 40–60 % of total house GHG emissions. The most beneficial options for disposal from a GHG perspective were landfill and incineration with energy recovery.

Conclusions

The study showed that significant GHG emission savings were achieved by optimising the use of wood products for two common house designs in Sydney. The switch of the sub-floor and floor covering components to a “wood” option accounted for most of the GHG savings. Inclusion of end of life parameters significantly impacted on the outcomes of the study.     

Dendroarchaeology at Lake Ohrid: 5th and 2nd millennia BCE tree-ring chronologies from the waterlogged site of Ploča Mičov Grad,North Macedonia

On the prehistoric site of Ploča Mičov Grad (Ohrid, North Macedonia) on the eastern shore of Lake Ohrid a total of 799 wooden elements were recorded from a systematically excavated area of nearly 100 square metres. Most of them are pile remains made of round wood with diameters up to almost 40 cm. A comprehensive dendrochronological analysis allows the construction of numerous well-replicated tree-ring chronologies for different species. High agreements between the chronologies prove that oak, pine, juniper, ash and hop-hornbeam can be crossdated. The chronologies are dated by means of radiocarbon dates and modelling using wiggle matching. An intensive settlement phase is attested for the middle of the 5th millennium BCE. Further phases follow towards the end of the 5th millennium BCE and in the 2nd millennium around 1800, 1400 and 1300 BCE. Furthermore, the exact, relative felling dates allow first insights into the minimum duration of the settlement phases, which lie between 17 and 87 years. The multi-centennial chronologies presented in this study can be used as a first robust dating basis for future research in the numerous not yet dated prehistoric lake shore settlements of the region with excellently preserved wooden remains.     

Palaeoclimatic records from peat bogs

The palaeoclimatic record for the past 6000 years, implemented from peat-bog stratigraphy, has been limited by imprecision in dating and climatic interpretation. Recently, dating problems have been addressed by 'wiggle-matched' radiocarbon dates and by volcanic ash layers, promising much tighter correlation between records from different regions. Recent research shows key dates of significant climatic change and tentative evidence for periodicity. Application of time-series analysis, generalized linear modelling and transfer function models to the proxy climate data show how improved climatic reconstructions can be obtained. Peat-derived palaeoclimatic data might explain, as well as describe, climatic changes over timescales of 102-103 years.     

Utilization,potential, and conservation ofAgathis,a genus of tropical Asian conifers

Agathis, kauri pine, is a genus of moderately fast-growing conifers, mainly of the tropical Far East, which produce a valuable timber and the resin Manila copal. Current knowledge and research in progress on its ecology, timber, resin, cultivation, seed storage, vegetative propagation, future potential and conservation are summarized.     

Empirical calibrated radiocarbon sampler: a tool for incorporating radiocarbon‐date and calibration error into Bayesian phylogenetic analyses of ancient DNA

Studies of DNA from ancient samples provide a valuable opportunity to gain insight into past evolutionary and demographic processes. Bayesian phylogenetic methods can estimate evolutionary rates and timescales from ancient DNA sequences, with the ages of the samples acting as calibrations for the molecular clock. Sample ages are often estimated using radiocarbon dating, but the associated measurement error is rarely taken into account. In addition, the total uncertainty quantified by converting radiocarbon dates to calendar dates is typically ignored. Here, we present a tool for incorporating both of these sources of uncertainty into Bayesian phylogenetic analyses of ancient DNA. This empirical calibrated radiocarbon sampler (ECRS) integrates the age uncertainty for each ancient sequence over the calibrated probability density function estimated for its radiocarbon date and associated error. We use the ECRS to analyse three ancient DNA data sets. Accounting for radiocarbon‐dating and calibration error appeared to have little impact on estimates of evolutionary rates and related parameters for these data sets. However, analyses of other data sets, particularly those with few or only very old radiocarbon dates, might be more sensitive to using artificially precise sample ages and should benefit from use of the ECRS.     

Low soil water and nutrient availability below New Zealand kauri (<Emphasis Type="Italic">Agathis australis</Emphasis> (D. Don) Lindl.) trees increase the relative fitness of kauri seedlings

Tree species can affect the soil they are growing on and this might influence their fitness. The New Zealand gymnosperm tree species kauri (Agathis australis (D. Don) Lindl.) which grows in mixed angiosperm–gymnosperm forests has a substantial effect upon the soil. We studied the hypotheses that: (1) low soil moisture availability below mature kauri trees hampers growth of kauri seedlings and angiosperm seedlings, (2) low nutrient availability below kauri trees hampers only angiosperm seedlings, and (3) angiosperm seedlings are hampered more than kauri seedlings by the conditions below kauri trees. We tested these hypotheses by planting seedlings of kauri and mapau (Myrsine australis (A. Rich) Allan) under kauri trees and applying the following treatments: removal of herbs, removal of litter, removal of nutrient limitation, and elimination of root competition of mature kauri trees. The results indicate that low soil moisture availability, or the combination of low soil moisture availability and low nutrient fertility, hampers the growth of kauri as well as mapau seedlings below kauri trees. The mapau seedlings are hampered relatively more than the kauri seedlings which might result in an increased relative fitness of the latter.