Pine Shoot Research Articles

PCR primers for identification of Sirococcus conigenus and S. tsugae, and detection of S. conigenus from symptomatic and asymptomatic red pine shoots

SummaryRegions of diversity in the internal transcribed spacer (ITS) sequences of Sirococcus species were exploited to design primer pairs used in a PCR‐based method for the identification of the conifer shoot blight pathogen Sirococcus conigenus and the closely related fungus Sirococcus tsugae. The specificity of each primer pair for the respective fungus, detection limits and utility for detection from host material were confirmed. The S. conigenus primers were then used to detect this pathogen in tissues of symptomatic or apparently healthy red pine shoots collected at six locations in Wisconsin and Michigan and results compared with those obtained using a cultural assay. For needles, bark and wood of symptomatic shoots, the mean frequencies of detection of S. conigenus using the PCR‐based methods were consistent (≥7.5 out of 10) and always greater than for the cultural assay. Detection from symptomatic shoots using the cultural assay was more frequent from needles than from bark or wood. Both the PCR‐based method and the cultural assay detected S. conigenus in similar frequencies from asymptomatic shoots, although less frequently than from symptomatic shoots. The efficiency of the PCR‐based method and its utility for direct testing of host material should make it particularly useful in areas where multiple shoot blight pathogens are found.

Anatomical structure and localisation of lignin in needles and shoots of Scots pine (Pinus sylvestris L.) growing in a habitat with varying environmental characteristics

Anatomical structure and localisation of lignin in needles and shoots of Scots pine (Pinus sylvestris L.) growing in a habitat with varying environmental characteristics We investigated the influence of a habitat with varying environmental characteristics on the anatomical structure and localisation of lignin in needles and shoots of Scots pine (Pinus sylvestris L.). A dune in South-West Estonia was chosen as the study area because it has extreme environmental characteristics: primitive sandy soil, deficiency of water, heavy winds and high light exposure. Analysis showed that the needles of all age and the current-year shoots of pines growing on the foot of the dune had the largest average cross section, mesophyll and parenchyma areas. The degree of the lignification of needles at the foot, on the slope and on the top of the dune differed distinctly. Intensive lignification of the cellular walls of the xylem was observed in needles and shoots of the pines, growing at the foot, but not in the trees growing on the top of the dune. Analysis showed that the anatomical structure and localisation of lignin, both in needles and in shoots, depend on their age, the trees location (foot, slope or top of the dune) and soil mineral composition.

UV-induced NO<sub>y</sub> emissions in gas-exchange chambers enclosing Scots pine shoots: an analysis on their origin and significance

It is essential to have a thorough understanding of the sources and sinks of oxidized nitrogen (NOy) in the atmosphere, since it has a strong influence on the tropospheric chemistry and the eutrophication of ecosystems. One unknown component in the balance of gaseous oxidized nitrogen is vegetation. Plants absorb nitrogenous species from the air via the stomata, but it is not clear whether plants can also emit them at low ambient concentrations. The possible emissions are small and difficult to measure. The aim of this thesis was to analyse an observation made in southern Finland at the SMEAR II station: solar ultraviolet radiation (UV) induced NOy emissions in chambers measuring the gas exchange of Scots pine (Pinus sylvestris L.) shoots. Both measuring and modelling approaches were used in the study. The measurements were performed under noncontrolled field conditions at low ambient NOy concentrations. The chamber blank i.e. artefact NOy emissions from the chamber walls, was dependent on the UV irradiance and increased with time after renewing the Teflon film on chamber surfaces. The contribution of each pine shoot to the total NOy emissions in the chambers was determined by testing whether the emissions decrease when the shoots are removed from their chambers. Emissions did decrease, but only when the chamber interior was exposed to UV radiation. It was concluded that also the pine shoots emit NOy. The possible effects of transpiration on the chamber blank are discussed in the summary part of the thesis, based on previously unpublished data. The possible processes underlying the UV-induced NOy emissions were reviewed. Surface reactions were more likely than metabolic processes. Photolysis of nitrate deposited on the needles may have generated the NOy emissions; the measurements supported this hypothesis. In that case, the emissions apparently would consist mainly of nitrogen dioxide (NO2), nitric oxide (NO) and nitrous acid (HONO). Within studies on NOy exchange of plants, the gases most frequently studied are NO2 and NO (=NOx). In the present work, the implications of the emissions for the NOx exchange of pine were analysed with a model including both NOy emissions and NOy absorption. The model suggested that if the emissions exist, pines can act as an NOx source rather than a sink, even under relatively high ambient concentrations.

Feeding ecology of pine shoot beetles (Tomicus spp.) in tree crowns of Scots pine (Pinus sylvestris L.) stands under one-year outbreak

Studies were carried out in southern Poland during 2002–2006 in Scots pine stands under the effect of an outbreak of pine shoot beetles. The qualitative aspects of beetle feeding in tree crowns, studied on the basis of fallen shoots collected on experimental plots, are presented in this paper. The beetle numbers affected the age distribution of damaged shoots and the proportion of multiple attacks. The proportions of one-year-old shoots and the numbers of shoots with more than two attacks increased in the marginal part of the stand in the year of intensive feeding of beetles and in the subsequent year. A similar proportion of shoots with two attacks in both stands under investigations in individual study periods, with no relation to beetle numbers, does not permit to use this characteristic for forecasting purposes. The average length of tunnels in shoots attacked once reached 20 mm at maximum. The average length of tunnels (measured from the place of shoot disruption) was greater in shoots with two attacks than in shoots with a single one (<i>P</I> < 0.0001). The difference was not significant (<I>P</I> = 0.3429) only in stand B during the study season 2004–2005. The majority of the tunnels made in apical portions of shoots with two attacks damaged the tissue of apical shoots. The distance between the base of the second tunnel and the shoot apex in shoots with two attacks, and its significant (<I>P</I> < 0.01) linear relationship with the length of beetle tunnels, indicated a high nutritional quality of apical portions of shoots.

Shoot Blight Caused by Diplodia pinea on Afghan and Austrian Pines in Texas.

Shoot blight was observed on ornamental Afghan (Pinus eldarica) and Austrian pines (P. nigra) at several sites in metropolitan Dallas, TX in the summer of 2005. Shoots were stunted, cankered, often resinous, sometimes curled or crooked at the tips, and bore brown needles that often had been killed before full elongation. Pycnidia on necrotic needles, stems, and cones of each host species yielded conidia characteristic of the fungus Diplodia pinea. Individual conidia and hyphal tip transfers produced pure cultures confirmed as D. pinea using a species-specific PCR assay (1), which allows differentiation from the similar pine shoot blight pathogen D. scrobiculata. Five isolates (three from Afghan pine and two from Austrian pine) were tested for pathogenicity by inoculation of potted 1-year-old Afghan pine seedlings obtained from the Texas Forest Service Nursery. Elongating terminal shoots were wounded by removing a needle pair approximately 2 cm below the shoot apex. A 4-mm-diameter plug cut from an actively growing culture on water agar (WA) was placed fungus side down on the wound. Noncolonized WA plugs were placed on similarly wounded control seedlings. Nonwounded control seedlings also were used. Parafilm was wrapped around the shoots to hold the agar plugs in place and was removed 2 weeks later. Each treatment was applied to four seedlings. Five weeks after inoculation, 9 of the 20 inoculated seedlings (including at least one inoculated with each isolate) exhibited dieback of shoot tips. One wounded control seedling exhibited slight tip dieback, no other nonwounded or wounded control seedlings developed symptoms. Segments of shoots were harvested, surface disinfested, and incubated on WA to determine the presence of the pathogen. The pathogen was reisolated from 11 of the 20 inoculated seedlings but not from any control seedlings. To our knowledge, this is the first report of D. pinea as a cause of shoot blight of Afghan pine and the first substantiated report of the occurrence of D. pinea in Texas. Although widely distributed in much of eastern North America, reports of the presence of D. pinea in the other southern gulf coast states of Alabama, Louisiana, and Mississippi, as well as the western states of Colorado, New Mexico, and Utah, are lacking. Reference: (1) D. R. Smith and G. R. Stanosz. Plant Dis. 90:307, 2006.

Detection of Diplodia pinea in asymptomatic pine shoots and its relation to the Normalized Insolation index

Summary Diplodia pinea (syn. Sphaeropsis sapinea), a common pathogenic fungus, causes considerable damage in Italy, particularly to pine stands in which trees are subjected to environmental stress. The occurrence of D. pinea in symptomless Pinus nigra shoots was investigated and related to the amount of radiation received by the trees growing on a site in a year, expressed as the Normalized Insolation index (NIi). Twenty‐seven pines were selected from nine locations in Trentino (northern Italy). For each pine the incidence of the fungus in apparently healthy shoots was determined by both culturing on an agar medium and application of real‐time PCR. The incidence of D. pinea determined by culturing samples taken from asymptomatic trees was 59% (16 of 27 trees), compared with 85% found using real‐time PCR (23 of 27 trees). Detection of the pathogen in healthy pine tissue was positively correlated (p < 0.05) with the NIi values, using both detection methods.

Spatial distribution of fallen shoots of Scots pine pruned by pine shoot beetles (Tomicus spp.), and evaluation of methods of shoot collection in central Poland

Methods of spatial distribution of fallen shoots, pruned by pine shoot beetles, and estimation of efficiency of methods based on collection of fallen shoots and used in forecasting of the occurrence of these insects, are presented in this paper. The fallen shoots were distributed in clusters. The distribution was statistically different from random. Relative errors in estimation of shoot-fall density were the smallest in study transects. Early and late autumn and the following spring, after the snow melt, are the optimum seasons for collecting fallen shoots.

How do the Epidemics of Gremmeniella abietina Start?

Gremmeniella abietina type A caused two widespread epidemics in Nordic countries: in 1982 in Finland and in 2001 in Sweden. The reasons for these epidemics are discussed based on the inoculation experiments in Finland and the literature. The fungus has been inoculated by putting a piece of mycelium in the phloem or by spraying the conidia or ascospores on pine shoots. Mycelial inoculations cause cankers in dormant period inoculations, but not in summer inoculations. During the dormant period, pine cannot actively defend against the fungus. Spore inoculations are successful in summer, which is also the natural spreading time of the fungus. The reason for infection seems to be poor structural resistance in infected shoots. Firstly the fungus infects the bract and during the dormant period it grows to the phloem through poorly developed cork layers between the dead bract and living phloem. A serious epidemic needs a rainy and cloudy summer and also the same kind of summer two years before. A mild winter enhances the growth in cankers, but a mild winter alone cannot cause the epidemics. Gremmeniella abietina damage is controlled by using local or a little bit of northern provenances.

Detection of Diplodia pinea in Asymptomatic Pine Shoots

Diplodia pinea is a fungal pathogen that causes tip blight shoot on several conifers trees. During the last few years the occurrence of this fungus in symptomless pine shoots, has been investigated on Austrian pine (Pinus nigra A.) pinewoods located in Central and Northern Italy. Fungal detection from apparently healthy samples was performed by using both isolation of pine tissue on agarized media but also by the real-time PCR. Differences between two sampled pinewoods were found showing a different behaviour of the fungus in the host.

Differences in Occurrence and Co-occurrence of Sirococcus conigenus and Diplodia pinea on Blighted Red Pine Shoots

Blighted red pine shoots, either having symptoms only on the most recent year’s growth or having symptoms present both on most recent and previous year’s growth, were examined for pycnidia of Sirococcus conigenus, Diplodia pinea, or both. On shoots having symptoms only on the most recent year’s growth, S. conigenus was detected more frequently than D. pinea. On shoots having symptoms on both the most recent and the previous year’s growth, however, D. pinea was detected more frequently than S. conigenus on the most recent year’s growth. In addition, on those shoots having symptoms on both the most recent and the previous year’s growth, D. pinea was detected almost eight times more frequently on the previous year’s growth than the most recent year’s growth. Whether only one pathogen was detected or the two pathogens were detected co-occurring on a single year’s growth also varied with shoot condition and shoot year of growth, but the two fungi co-occurred on shoots of each condition.

Breeding performance and longevity of Tomicus destruens on Mediterranean and continental pine species

AbstractThe pine shoot beetle Tomicus destruens (Wollaston) (Coleoptera: Curculionidae: Scolytinae) is one of the main pests of Mediterranean forests, where it is oligophagous on Mediterranean pines. However, possible global warming may make the insect move to higher latitudes and altitudes, allowing it to attack new pine species. In this respect, the aim of the present article was to assess both the acceptance and performance of T. destruens offered host and non‐host pine species. A no‐choice breeding experiment was set up under laboratory conditions, using logs of three Mediterranean (Pinus pinea L., Pinus pinaster Miller, and Pinus halepensis Aiton) and two continental (Pinus nigra Arnold and Pinus sylvestris L.) pine species. Log debarking at the end of adult emergence assessed parent fecundity, egg, and larval mortality. The quality of callow adults emerging from each tested pine was evaluated on the basis of their longevity on a semiartificial diet. Tomicus destruens colonised all tested pine species, but did not reproduce in Scots pine, taking about 79 days to complete development with no differences among pines tested. The best breeding performance, evaluated as female fecundity and adult production, was observed in P. halepensis, and the lowest in P. pinaster. On average, adults emerging from P. pinea survived longer (83 days) than from other pines, and adult longevity was the lowest in males emerging from P. nigra. Austrian pine, which under natural conditions is usually not a host of T. destruens, allowed insect development and adult production similar to P. pinea and P. pinaster.

C-band scattering simulation of a Scots pine shoot

Scots pine (Pinus sylvestris L.) has the widest distribution of any pine and is one of the most important timber trees in Europe and one of the main species of boreal forest, which have an important role in climate change studies. The leaf area index (LAI) is one of the key input parameters for the climate change models. Recently a relationship between C-band backscattering and the LAI has been detected for Scots pine. To understand the C-band microwave characteristics of Scots pine shoots the backscattering is simulated using the so-called discrete dipole approximation (DDA), which is the only possible, nearly exact method for this problem. The backscattering of the shoot is dominated by the needles. The VV/HH backscattering ratio of closely spaced parallel and perpendicular shoots averages to that of a single shoot. For a simulated whole Scots pine crown the VV/HH backscattering ratio is related to the total orientation distribution of the needles. The variation range of the VV/HH backscattering ratio was 0.95–1.25, which is close to empirical values.

Temporal trends and spatial distribution of PCDD, PCDF, and PCB in pine and spruce shoots

In Germany, there is a lack of consistent and comparable data for the time dependent behaviour and spatial distribution of dioxin-like and indicator PCB in ambient air, deposition and plants. The aim of this study was to improve the data on PCDD/PCDF, dioxin-like PCB and non dioxin-like PCB in spruce and pine shoots from different locations and years by retrospective monitoring. The survey was conducted with archived samples of one-year old spruce shoots (Picea abies) and pine shoots (Pinus sylvestris) from the German environmental specimen bank. Two sets of samples from locations in urbanized areas in western and eastern Germany (Warndt and Duebener Heide Mitte, respectively) were investigated as time series. Additionally, spruce shoots from seven different rural locations sampled in the years 2000-2004 were analyzed in order to get an overview about the spatial distribution of PCB and PCDD/PCDF. The analytical results of the samples from the two urbanized areas clearly show that the atmospheric contamination with PCDD and PCDF has declined by about 75% between 1985 and 1997 at Warndt and about 40% between 1991 and 1997 at Duebener Heide. However, concentrations stayed virtually constant at both locations from 1997 to 2004 at a level of about 1 ng WHO-TEQ/kg dry matter (d.m.). Similarly, the investigation of spruce shoots from rural locations from 2000 to 2004 did not reveal a temporal trend at any site. PCDD/PCDF levels were between 0.1 and 1.0 ng WHO-TEQ/kg d.m. At the urbanized location Warndt the six indicator PCB as well as the 12 dioxin-like PCB according to WHO revealed a significant decline by more than 75% between 1985 and 1999. Thereafter, PCB levels stayed virtually constant. At the location Duebener Heide an overall decrease of PCB concentrations in pine shoots of about 60% was detected between 1991 and 2004. Spruce shoots from all locations showed a relevant contribution of dioxin-like PCB to the total WHO toxicity equivalent (PCDD/PCDF+PCB). In most samples, the contribution of dioxin-like PCB was between 21% and 41%. The TEQ contribution of PCB in the samples from three rural sites was higher and similar to the TEQ value of PCDD/PCDF. The investigated pine shoots from the urbanized site Duebener Heide showed a 15-28% contribution of dioxin-like PCB to total TEQ and thus lower than in spruce shoots from different locations. In all samples except one PCB 126 contributed to more than 80% to the PCB-TEQ.

Histology of Diplodia pinea in diseased and latently infected Pinus nigra shoots

SummaryDiplodia tip blight is a serious disease of >30 conifer species worldwide. Symptoms are particularly severe on non‐native, two‐needled Pinus species, and typically include stunted, necrotic needles and shoots and a general decline of the tree. Latent Diplodia pinea infections occur in current‐year shoots of some symptomless pines, and in some apparently healthy current‐year shoots of diseased pines. Latent infections also occur in symptomless terminal buds. A histological approach was used to investigate the nature of latent infections in shoot stems and terminal buds of landscape Pinus nigra. Fungal colonization was compared in healthy, diseased and latently infected tissues. A nested‐PCR technique that is specific for D. pinea was used to differentiate latently infected tissues from uninfected ones. Latent D. pinea infections were localized in the outer stem cortex, usually in the vicinity of needle scales at leaf axes. In contrast, pathogenic D. pinea infections were characterized by fungal colonization throughout the shoot stem tissues, even very early in symptom development. The presence of necrophylatic periderms in two of the latently infected samples suggests that host defences play a role in the production and maintenance of latent stem infections. Latent infections of terminal buds appeared to originate from the distal bud scales of axillary buds in the terminal bud cluster, and not from the subtending shoot. Fungal tissues were never observed inside asymptomatic, PCR‐negative shoots.

Influence of Fungal Infection and Wounding on Contents and Enantiomeric Compositions of Monoterpenes in Phloem of Pinus sylvestris

To identify chemical resistant markers induced by fungal or mechanical injury, young trees of Scots pine (Pinus sylvestris) were subjected to inoculations of blue stain fungi associated with the pine shoot beetles Tomicus piniperda and T. minor. Among the 20 trees selected for chemical analyses, 16 were divided into four groups: one as control and three were pretreated by wounding only, or by inoculation with either the blue stain fungus Leptographium wingfieldii or Ophiostoma canum. Four wk after pretreatment, all 16 pretreated trees were mass-inoculated with L. wingfieldii. The absolute and relative amounts, as well as the enantiomeric compositions of monoterpene hydrocarbons in the phloem, were determined via a small sample of the phloem before and after the pretreatment and mass inoculation, by using two-dimensional gas chromatography (2D GC) and GC-mass spectrometry (MS). After mass inoculation, the absolute amounts of most of the monoterpenes decreased in the phloem sampled >20 cm from the fungal infection, and were higher in the phloem sampled within the infected reaction zone. The relative amounts of both (-)-beta-pinene and (-)-limonene increased in phloem samples taken >20 cm above the fungal inoculation in the preinoculated trees compared with phloem sampled from the remaining four control trees. The enantiomeric compositions of beta-pinene and limonene changed, after fungal growth, at defined distances from the inoculation site: the proportion of the (-)-enantiomers was highest in the phloem sampled >20 cm from the fungal inoculation. Four wk after pretreatment, monoterpene production in the phloem at the site of inoculation was more enhanced by L. wingfieldii than by O. canum. However, the different virulence levels of the fungi did not affect the enantiomeric composition of the monoterpenes. The biosynthesis of monoterpene enantiomers is discussed in relation to induced pathogen resistance.

UV-induced NO y emissions from Scots pine: Could they originate from photolysis of deposited HNO 3?

Production of NO y on Scots pine branch surfaces by ultraviolet radiation is observed in Hyytiälä, southern Finland. Similar irradiance-dependent NO y emissions from snow and different chamber surfaces have been observed to originate from HNO 3 or nitrate photolysis. In this study, we investigate whether also the NO y emitted from pine shoots could originate from photolysis of HNO 3 attached to the needle surface. We used field data of several years from Hyytiälä to test this hypothesis. The HNO 3 deposition, estimated for the Hyytiälä site, had been high enough to account for the NO y emission rates observed from the chambers. We could not find the particular characteristics of the daily pattern of CO 2 exchange or stomatal control reflected in the NO y flux. When a pine branch was rinsed, which reduced the amount of water-soluble nitrogen compounds (e.g., HNO 3, nitrates and HONO) from the needle surface, NO y emissions from that branch decreased compared to another non-rinsed branch. Therefore, we conclude that the results support the hypothesis and that HNO 3 photolysis on plant surfaces needs to be taken into account both from air chemistry and plant sciences point of view.

Effects of forest management on the abundance of insect pests on Scots pine

We compared the degree of needle damage and the abundance of common insect pests in Scots pine stands on the Finnish and Russian sides of the border on the Karelian Isthmus. The study areas have similar climatic and geological conditions, but the intensity of forest management has been much higher on the Finnish side of the border during the past 50 years. In Finland all stands are thinned once or twice during the rotation period, while there are no thinnings in the Russian side. The density of the Scots pine stands and the proportion of dead trees were significantly higher on the Russian side of the border. Needle damage caused by folivorous insects was about eight times higher in the non-managed forests of Russian Karelia compared to the managed Finnish forests. Shoot twigs damaged by pine shoot beetles ( Tomicus spp.) – the dominant bark beetle on Scots pine – and the number of egg clusters of the European pine sawfly ( Neodiprion sertifer) – the dominant defoliator, respectively – were also more abundant in samples collected from the trees on the Russian side of the border. There were, however, no differences in the number of aphid eggs or in the number of galls caused by Eversia resinella. Therefore, intensive forest management in Finland has changed the susceptibility of pine forests to insect pests compared to the situation in semi-natural forest on the Russian side of the border. However, these effects varied in accordance with the insect feeding guild. Especially bark beetles depending on recently dead trees benefit on unthinned forests where natural mortality of trees is high.

Host Selection in Tomicus piniperda L.: Composition of Monoterpene Hydrocarbons in Relation to Attack Frequency in the Shoot Feeding Phase

The aim of this study was to investigate the host selection capacity of the pine shoot beetle, Tomicus piniperda, in the shoot-feeding phase and analyze the chiral and non-chiral host volatiles by means of GC-MS and 2D-GC in five Pinus species originating from France (Pinus sylvestris, P. halepensis, P. nigra laricio, P. pinaster maritima, P. pinaster mesogeensis). Dominating monoterpenes were (-)-alpha-pinene, (+)-alpha-pinene, (-)-beta-pinene and (+)-3-carene. The amounts of the enantiomers varied considerably within and among the species. In a principal component analysis-plot, based on the absolute amounts of 18 monoterpene hydrocarbons, separation of the pine species into two groups was obtained. P. halepensis and P. sylvestris were grouped according to the amount of (+)-alpha-pinene and (+)-3-carene, while P. nigra laricio, P. pinaster maritima and P. pinaster mesogeensis were grouped according to (-)-alpha-pinene and (-)-beta-pinene. P. nigra laricio was the species most attacked and P, halepensis the one least attacked by T. piniperda.

Distribution and population genetic structure of the Mediterranean pine shoot beetle Tomicus destruens in the Iberian Peninsula and Southern France

Abstract1 The Mediterranean pine shoot beetle Tomicus destruens has long been indistinguishable from its congeneric Tomicus piniperda. Both species attack pines, and can be found in sympatry. The geographical distribution of T. destruens is still unclear in most of the Mediterranean Basin.2 We aimed to describe the geographical distribution and zones of sympatry of both species in the Iberian Peninsula and France, and to study the molecular phylogeographical pattern of T. destruens.3 Tomicus spp. adults were sampled in Portugal, Spain and France, and a portion of the mitochondrial genes COI and COII was sequenced for 84 individuals. Sequences were aligned to a data set previously obtained from French localities.4 Tomicus destruens was found in all populations, except for one locality in Portugal and in the Landes (France). It was in sympatry with T. piniperda in two locations on Pinus pinaster and one location on Pinus radiata.5 Within‐population genetic diversity was high, but we found a significant pattern of spatial distribution of genetic variation, as well as a significant effect of the host tree.6 The data suggest the existence of two glacial refugia, from which T. destruens recolonized its current range. One refugium was located in Portugal where the beetle probably evolved on P. pinaster. The corresponding haplotypes show a West–East frequency gradient. The other refugium was probably in the eastern range, where the beetles evolved on Pinus halepensis and P. pinea. The corresponding haplotypes show an East–West frequency gradient.

Spatial distribution of losses in growth of trees caused by the feeding of pine shoot beetles Tomicus piniperda and T. minor (Col., Scolytidae) in Scots pine stands growing within range of the influence of a timber yard in southern Poland

This study deals with the assessment of increment losses in Scots pine trees caused by the maturation feeding of pine shoot beetles Tomicus piniperda (L.) and T. minor (Hart.) (Col., Scolytidae) in even-aged stands growing during their entire life span within range of the influence of a sawmill and its timber yard. In spring 2004, on three sample plots, 0.2 ha in size, situated 60, 200, and 500 m from the yard, height and dbh of all trees were measured and increment cores were taken from randomly selected sample trees. An agreement between the spatial distribution of losses in tree increments and the distribution of damage to crowns of investigated stands indicated that the losses resulted from the maturation feeding of pine shoot beetles migrating from the sawmill timber yard. Divergence of growth in the about 25-years-old stand indicated the beginning of intensive feeding of beetles in pine shoots with a high level of probability. In comparison with the control stand the basal area losses in stands growing 60 and 200 m from the beetle source amounted to 57% and 46%, respectively. The difference in the height of trees was as large as almost 100%.