Red Oak Trees Research Articles

Use of Nested and Real-Time PCR for the Detection of Ceratocystis fagacearum in the Sapwood of Diseased Oak Species in Minnesota.

Oak wilt caused by Ceratocystis fagacearum is a significant disease of Quercus spp. in the eastern United States. Early and accurate detection of the pathogen is particularly important when disease control is planned. Nested and real-time polymerase chain reaction (PCR) methods utilizing fungal DNA extracted from sapwood drill shavings of red, bur, and white oak at different stages of disease development were compared with culture-based detection from sapwood. The pathogen was detected in all (n = 3) actively wilting branches of each of nine red oak trees using all three methods. The lowest detection rate (33% of assayed branches; 6 of 8 trees) for actively wilting branches was found for white oak using isolation while nested PCR had a branch detection rate of 100% (8 of 8 trees) and real-time PCR of 87% (8 of 8 trees) for the same samples. For both bur and white oak, the pathogen was not detected by isolation in branches over 1 year after their death but was detected using both PCR methods. Only the PCR assays detected the fungus in sapwood samples underlying remnants of sporulation mats (n = 21; 90%, nested and 62%, real-time) on red oak. These PCR methods offer several significant improvements for laboratory-based detection methods of C. fagacearum.

Mineralogical and micromorphological characteristics of red pineand oak root zone soils in southern Turkey

Plant species exert differential effects on soil mineralogical and micromorphological characteristics. The effect of red pine and oak tree roots on the mineralogical and micromorphological characteristics of rhizosphere soils in two sampling sites in the Goksu catchment was studied. The climate, topography, and bedrock conditions were kept consistent, whereas the plant factor was kept as the only variable in each site. Rhizosphere soils under the canopies of 100 years old and naturally occurring trees were compared via macromorphology, submicroscopy, mineralogy, and physical and chemical properties. The soils of red pine (RP1 and RP2 profiles) were determined to have higher porosity when compared to the soils of the oak tree profiles (Ok1, Ok2). However, the higher amounts of welded/cemented aggregates in the Ok1 and Ok2 profiles were probable indicators of maturity and probable stability of the aggregates/MSUs. The dominant clay mineral in sampling site 1 was kaolinite, whereas it was smectite in sampling site 2.

Growth and stability of deep planted red maple and northern red oak trees and the efficacy of root collar excavations

Trees with root systems established well below grade due to deep planting or soil disturbance are common in urban landscapes, yet the long term effects of buried trunks and subsequent remediation strategies, such as root collar excavation are poorly documented. We evaluated the consequences of deep planting over a 10-year period on tree growth and stability, with and without root collar excavation, for red maple [Acer rubrum L. Red Sunset® (‘Franksred’)] and Northern red oak (Quercus rubra L.) planted at grade or 30-cm below grade. Sleeves to prevent soil-trunk contact were installed around trunks on a subset of deep trees. Root collar excavations were made during the 6th growing season for both species and trees were grown for an additional 4 and 3 growing seasons for red maples and Northern red oaks, respectively. Within two weeks of root collar excavations, pulling tests compared the effect of treatments on stability of red maples. Deep planting generally slowed growth of red maple but had no clear effect on Northern red oak. Root collar excavation had no lasting effect on growth of either species. Approximately 55% of deep red maples and 33% of deep Northern red oaks had roots crossing and in intimate contact with buried trunks, suggesting a potential for future girdling roots. Approximately 25% of deep maples had substantial adventitious rooting. All deep Northern red oaks had new roots emerging just above the first original structural roots but none were clearly adventitious. Trunk sleeves had no effect on growth for either species. Neither deep planting nor root collar excavation resulted in a loss of tree stability compared to trees planted at grade, although failure patterns varied among treatments. Overall, the biggest long term concern for deep-planted trees is the potential for girdling root formation.

Tardigrades of the Canopy: Argentine SpeciesMilnesium beataeRoszkowska, Ostrowska and Kaczmarek, 2015 (Eutardigrada, Milnesidae) Discovered in the Trees of Kansas, U.S.A.

During the summer of 2015, a recently described species of tardigrade from southern Argentina, Milnesium beatae Roszkowska, Ostrowska and Kaczmarek, 2015, was discovered in the canopy of trees in Kansas, USA. Seven specimens of the southern hemisphere species were collected from lichen habitat above six meters on red oak tree substrates in a tree island on the edge of the tall grass prairie. Statistical comparison of the characteristics of the specimens of the two populations demonstrates that they are morphologically the same. Two new characters are described: first, small cuticular bars at the base of legs IV and second, thin plates (pseudoplates) in the dorsal and lateral cuticle are exposed by UV fluorescence imagery. Bird nesting habits and migration patterns are explored to explain how the same species of microscopic water bear is known to only occur at disparate locations 9,000 km apart in different hemispheres.

Ecosystem warming increases sap flow rates of northern red oak trees

AbstractOver the next century, air temperature increases up to 5°C are projected for the northeastern United States. As evapotranspiration strongly influences water loss from terrestrial ecosystems, the ecophysiological response of trees to warming will have important consequences for forest water budgets. We measured growing season sap flow rates in mature northern red oak (Quercus rubra L.) trees in a combined air (up to 5.5°C above ambient) and soil (up to 1.85°C above ambient at 6‐cm depth) warming experiment at Harvard Forest, Massachusetts, United States. Through principal components analysis, we found air and soil temperatures explained the largest amount of variance in environmental variables associated with rates of sap flow, with relative humidity, photosynthetically active radiation and vapor pressure deficit having significant, but smaller, effects. On average, each 1°C increase in temperature increased sap flow rates by approximately 1100 kg H2O m−2 sapwood area day−1 throughout the growing season and by 1200 kg H2O m−2 sapwood area day−1 during the early growing season. Reductions in the number of cold winter days correlated positively with increased sap flow during the early growing season (a decrease in 100 heating‐degree days was associated with a sapflow increase in approximately 5 kg H2O m−2 sapwood area day−1). Soil moisture declined with increased treatment temperatures, and each soil moisture percentage decrease resulted in a decrease in sap flow of approximately 360 kg H2O m−2 sapwood area day−1. At night, soil moisture correlated positively with sap flow. These results demonstrate that warmer air and soil temperatures in winter and throughout the growing season lead to increased sap flow rates, which could affect forest water budgets throughout the year.

Comparative Leaf Phenology of White Oak and Northern Red Oak

In the landscape, loss of interveinal tissue in developing leaves (leaf tatters) is common for white oak (Quercus alba L.), but not northern red oak (Quercus rubra L.). Previous research identified the cause of leaf tatters, as exposure of unfolding leaves, to low concentrations of chloroacetanilide herbicides. Both white oak and northern red oak were injured by these herbicides at the leaf unfolding stage. Reports from landowners suggest white oak is injured more often than red oak, leading us to theorize that white and northern red oak leaves emerge at different times, and white oaks were more likely to be at the leaf unfolding stage when chloroacetanilide herbicides are applied. A study of comparative leaf phenology of white and northern red oak was done at three sites in Urbana, IL. Identifying oak pairs was challenging, and at each location, four to six paired mature white oak and northern red oak trees were used to observe phenological events. Key development stages (swollen bud, leaf unfolding, or fully expanded leaf stages) were considered to have occurred when reached by greater than 50% of the canopy. Northern red oak expanded leaf stage occurred earlier when compared to white oak. Time between phenological events was similar for both species. Although northern red oak leaves emerged earlier, there was a range of emergence times within short distances. Difference between locations illustrates the problem in predicting tree phenology even among populations a few kilometers apart. Leaf phenology alone does not explain leaf tatters, and other factors including distribution differences in oak species must explain landowner observations of tree injury. There was a strong correlation between growth phases of the two oak species with cumulative growing degree days, cumulative rainfall, and day length.

Random sampling of skewed distributions implies Taylor’s power law of fluctuation scaling

Taylor's law (TL), a widely verified quantitative pattern in ecology and other sciences, describes the variance in a species' population density (or other nonnegative quantity) as a power-law function of the mean density (or other nonnegative quantity): Approximately, variance = a(mean)(b), a > 0. Multiple mechanisms have been proposed to explain and interpret TL. Here, we show analytically that observations randomly sampled in blocks from any skewed frequency distribution with four finite moments give rise to TL. We do not claim this is the only way TL arises. We give approximate formulae for the TL parameters and their uncertainty. In computer simulations and an empirical example using basal area densities of red oak trees from Black Rock Forest, our formulae agree with the estimates obtained by least-squares regression. Our results show that the correlated sampling variation of the mean and variance of skewed distributions is statistically sufficient to explain TL under random sampling, without the intervention of any biological or behavioral mechanisms. This finding connects TL with the underlying distribution of population density (or other nonnegative quantity) and provides a baseline against which more complex mechanisms of TL can be compared.

Nutrient cycling in an agroforestry alley cropping system receiving poultry litter or nitrogen fertilizer

Optimal utilization of animal manures as a plant nutrient source should also prevent adverse impacts on water quality. The objective of this study was to evaluate long-term poultry litter and N fertilizer application on nutrient cycling following establishment of an alley cropping system with eastern black walnut (Juglans nigra L.), pecan [Carya illinoensis (Wangenh.) K. Koch], and northern red oak (Quercus rubra L.) trees and orchardgrass (Dactylis glomerata L.). One half of a 4.25-ha site in northwestern Arkansas USA received broadcast applications of 3.9–6.7 Mg ha−1 fresh poultry litter and the other half 50–76 kg ha−1 N as NH4NO3 fertilizer each spring from 2001 to 2008. Macronutrient (N, P, K, Ca, Mg, and S) and micronutrient (Na, Fe, Mn, Zn, and Cu) concentrations in soil, forage, and tree leaf tissue were monitored along with NO3-N in soil water and groundwater. Poultry litter application resulted in significantly increased concentrations of each macronutrient except S with increases from 6.3 (N) to 121 % (P). Nitrogen fertilizer application resulted in decreased concentrations from 2.1 (N) to 60.9 % (S) for all macronutrients except Ca. Patterns of nutrient content in forage and tree leaf tissue did not generally follow patterns of soil nutrient concentrations suggesting nutrient sufficiency in most years and that climate and plant growth had a greater effect on nutrient uptake. Soil P with litter application increased 41.3 mg kg−1 over 7 years (from 34.1 to 75.4), which may necessitate a lower litter application rate to avoid excessive P runoff.

Influence of nursery production system on water status in transplanted trees

The objective of this study was to investigate the influence of the nursery production system on post-transplant water uptake and stress in urban trees during the establishment phase. Field-grown trees of sweet cherry (Prunus avium L) and red oak (Quercus rubra L) were either transplanted as bare-rooted or balled & burlapped, or subjected to fine-root-stimulating measures (in so called pre-establishing systems) as root-pruning, air-potting or fabric-container-cultivation in the nurseries one year prior to transplanting. All trees were planted at two sites: one occasionally dry site in the city of Malmö and one with adequate water supply at all times, at an experimental rural site at Alnarp campus, both in Sweden. Shoot water potential was determined every third week at midday and pre-dawn the following morning during the three first years after transplanting. Leaf surface area was measured annually. The red oak trees from the pre-establishing systems showed higher water potentials at every measuring occasion compared to that of bare-rooted red oak trees at the rural site during the first year. The air-potted sweet cherry trees at the rural site had higher midday water potential than the bare-rooted trees at every measuring occasion during the first year. Leaf surface area was larger for air-potted red oaks than bare-rooted red oaks during the first post-transplant year (p<0.001, both sites). The differences between the production systems did not persist during the following two years. Leaf surface area was restored to pre-transplant size in all trees at the rural site after three years but still reduced at the urban site. These results suggest that the pre-establishing systems do have an impact on water status when soil water availability is sufficient, but less significance in typically urban areas, with limited soil water during the initial post-transplant phase. The results indicate that red oak and sweet cherry trees planted in an urban context, with occasionally low soil water amounts, are not favored by cultivation in pre-establishing systems prior to transplant, and that low water availability cannot be compensated for by high amounts of fine roots. Good establishment management is required also for trees submitted to pre-establishing measures.

Fire damage effects on red oak timber product value

Land managers use prescribed fire for a variety of resource objectives on sites containing merchantable trees. We analyzed how fire-caused injuries (i.e., fire scars) affect lumber volume and value in 88 red oak (Quercus velutina, Quercus rubra, and Quercus coccinea) butt logs from trees harvested from three sites in southern Missouri. Trees with varying amounts of external fire damage, time since fire, and diameter were harvested and milled into dimensional lumber. We tracked lumber grade changes and volume losses due to fire-related injuries on individual boards (n=1298, 18.3 cubic meters (7754 board feet)). Most analyses considered value loss to the individual butt log. We identified threshold values for fire-scar height and percent basal circumference injured, beyond which value loss is expected. Our analysis produced two models to describe how butt log value loss relates to fire-scar dimensions and residence time (timespan between damage occurrence and tree harvest). Overall, value and volume losses due to fire damage were low. If fire damage is less than 50cm in height and 20% of basal circumference, our study suggests little value loss is to be expected within 14years of injury. If these thresholds are exceeded, value loss is likely, and increases over time. Value loss is very low if trees are harvested within approximately five years after fire damage, regardless of scar size. These findings are applicable for red oak trees which are at least 20cm diameter at breast height at time of fire damage and with fire-scar residence times not greater than fourteen years.

The Competition between Liquid and Vapor Transport in Transpiring Leaves

In leaves, the transpirational flux of water exits the veins as liquid and travels toward the stomata in both the vapor and liquid phases before exiting the leaf as vapor. Yet, whether most of the evaporation occurs from the vascular bundles (perivascular), from the photosynthetic mesophyll cells, or within the vicinity of the stomatal pore (peristomatal) remains in dispute. Here, a one-dimensional model of the competition between liquid and vapor transport is developed from the perspective of nonisothermal coupled heat and water molecule transport in a composite medium of airspace and cells. An analytical solution to the model is found in terms of the energy and transpirational fluxes from the leaf surfaces and the absorbed solar energy load, leading to mathematical expressions for the proportions of evaporation accounted for by the vascular, mesophyll, and epidermal regions. The distribution of evaporation in a given leaf is predicted to be variable, changing with the local environment, and to range from dominantly perivascular to dominantly peristomatal depending on internal leaf architecture, with mesophyll evaporation a subordinate component. Using mature red oak (Quercus rubra) trees, we show that the model can be solved for a specific instance of a transpiring leaf by combining gas-exchange data, anatomical measurements, and hydraulic experiments. We also investigate the effect of radiation load on the control of transpiration, the potential for condensation on the inside of an epidermis, and the impact of vapor transport on the hydraulic efficiency of leaf tissue outside the xylem.

A comparative study of physiological and morphological seedling traits associated with shade tolerance in introduced red oak (Quercus rubra) and native hardwood tree species in southwestern Germany

Northern red oak (Quercus rubra L.), a moderately shade-tolerant tree species, is failing to regenerate throughout its native North American range, while successful recruitment in Central Europe has been observed since its introduction. To examine whether comparative photosynthetic performance could explain the regeneration success of this non-native species in Central Europe, we compared the physiological and morphological seedling traits of red oak with three co-occurring tree species under three canopy types in southwestern Germany. Native species included a moderately shade-tolerant native oak (Quercus robur L.) and two shade-tolerant species (Acer pseudoplatanus L. and Carpinus betulus L.). The photosynthetic traits of non-native red oak seedlings were similar to those reported for this species in the native range, where shade-tolerant competitors readily outperform red oak under low light conditions. However, compared with native shade-tolerant species in Europe, red oak seedlings photosynthesized efficiently, especially under closed canopies and in small canopy gaps, exhibiting high photosynthetic capacity, low leaf dark respiration and leaf-level light compensation points that were similar to the more shade-tolerant species. The superior net carbon gain of red oak seedlings at low and moderate light levels was likely facilitated by high leaf areas and reflected by seedling dry masses that were greater than the observed native European species. A competitive advantage for red oak was not evident because relative height growth was inferior to seedlings of co-occurring species. In North America, the inability of seedlings to compete with shade-tolerant tree species in deeply shaded understories is central to the problem of poor oak recruitment. Our study suggests that the ability of non-native red oak to perform equally well to native shade-tolerant species under a variety of light conditions could contribute to the consistent success of red oak regeneration in Europe.

Draft Genome Sequence of Xylella fastidiosa subsp. multiplex Strain Griffin-1 from Quercus rubra in Georgia

The draft genome sequence of Xylella fastidiosa subsp. multiplex strain Griffin-1, isolated from a red oak tree (Quercus rubra) in Georgia, is reported here. The bacterium has a genome size of 2,387,314 bp, with a G+C content of 51.7%. The Griffin-1 strain genome contains 2,903 predicted open reading frames and 50 RNA genes.

English

On a surface coal mine in southern West Virginia, the forestry reclamation approach was applied while quantifying the effects of substrate type and seeding prescription on survival and growth of native tree species and herbaceous vegetation. Four substrates were used: weathered sandstone (brown), unweathered sandstone/shale mix (gray), mixture of weathered and unweathered rock (mixed), and a mixture of the soil solum and unconsolidated soil parent material (soil). Each substrate treatment was split into two subplots; one seeded with a tree-compatible herbaceous seed mixture and one unseeded. Trees were planted in March 2012, measured for initial height in June 2012, and measured for height and survival in late October 2012. Herbaceous groundcover and species richness were measured during the growing season. After one growing season, mean percent survival and growth of planted trees differed among tree species and seeding treatments. There were no differences in tree survival among substrate treatments. Of planted tree species, survival was higher for hawthorn and black cherry (~85%) than for most other species and lowest for Eastern white pines (25.3%) and shagbark hickory (24.3%). Unseeded treatments had higher tree survival (70.4%) than seeded treatments (56.4%). Of the trees which survived the first growing season, black cherry, red oak, sugar maple, and white oak showed differences in height growth related to experimental treatments. Black cherry and red oak trees grew more in the unseeded treatment, compared to the seeded treatment. White oaks grew the most in the brown sandstone treatment. Sugar maples grew the most in the seeded mixed treatment. Gray and soil substrate treatments had the highest total herbaceous richness and the soil treatment had the highest volunteer richness. Seeded treatments had less bare ground and higher mean herbaceous species richness than unseeded subplots. Leaving the landscape unseeded facilitated tree establishment, but the impact of seeding on the future understory community remains unclear. Soil appears superior to rock spoils for re-establishing a diverse understory. We expect that the influence of substrate and seeding treatments will become clearer after additional growing seasons.

White‐tailed deer (Odocoileus virginianus) positively affect the growth of mature northern red oak (Quercus rubra) trees

Understanding and predicting the effects of deer (Cervidae) on forest ecosystems present significant challenges in ecosystem ecology. Deer herbivory can cause large changes in the biomass and species composition of forest understory plant communities, including early life‐cycle trees (i.e., seedlings and saplings). Such changes can impact juvenile to adult transitions and the future age structure and species composition of mature forests. Changes to understory vegetation also impact flow of energy and nutrients in forest ecosystems. Studies examining the influence of deer on mature trees, however, are rare and rely on extrapolating effects from early life cycle stages of trees. We tested the hypothesis that the absence of deer would result in an increase in the growth rate of mature trees by examining the impact of white‐tailed deer (Odocoileus virginianus) on mature canopy trees. We examined incremental growth in individuals of Quercus rubra, an important component of temperate deciduous forests in North America, inside and outside 16‐year deer exclosures in eastern U.S. deciduous forests. We found that adult trees inside exclosures grew less than those directly exposed to deer. Our findings highlight the indirect effects of white‐tailed deer on the growth of adult individuals of Q. rubra in a way opposite of what would be expected from previous studies based on immature or understory tree populations. We suggest the increased growth of adult trees in the presence of deer may be explained by increased nutrient inputs through deer fecal and urine deposits and the alteration of the competitive environment belowground through the reduction of understory vegetation by browsing. Underscoring the ecological and demographic importance of adult trees in forest ecosystems, results from this study suggest the direct and indirect effects of deer on mature trees should not be overlooked.

Occlusion of pruning wounds on northern red oak (Quercus rubra) trees in Romania

This study focuses on the occlusion of pruning wounds on northern red oak (Quercus rubra L.) trees grown in two plantations established in the south-east of Transylvania, Romania in 1997 and 2004. In total, 184 green branches of elliptical cross section (i.e. with the horizontal axis Ha shorter than vertical axis Va and ranging between 0.6 cm and 4.5 cm) were pruned in April 2007 and May 2009. Of these branches, 161 (88%) were fully occluded after five growing seasons and, the majority of these, 148 wounds (80%), had occluded in three seasons. The main factors affecting the wound occlusion on trees subject to artificial pruning are diameter at breast height increment and branch size: the occlusion is more rapid in trees with faster diameter growth rates and on small branches of maximum 3 cm Ha. Consequently, artificial pruning should be concentrated on small branches on well formed, vigorous and evenly spaced final crop trees which can subsequently be favoured by heavy and targeted thinning from above, allowing the production of large diameter, high-quality trees in 50–70 years.

Wood discolouration in relation to wound size in northern red oak (Quercus rubra L.) trees subject to artificial pruning

Wood discolouration in relation to wound size in northern red oak (Quercus rubra L.) trees subject to artificial pruning

Host selection and responses to forest fragmentation in acorn weevils: inferences from dynamic occupancy models

Prior studies on species‐specific responses to habitat alteration have demonstrated that niche breadth is positively associated with patch occupancy rates in landscapes fragmented by agriculture. However, these studies generally have focused on vertebrates and relied upon data collected at a single point in time, neglecting dynamic processes that could alter inferences. We studied the effects of host selection and forest fragmentation on population dynamics of acorn weevils Curculio, the primary insect seed predators of oaks in North America. Detection/non‐detection data were collected from 174 red and white oaks in 19 forested fragments from 2005–2008. We used dynamic multi‐season site‐occupancy models within a Bayesian framework to explore variation in patch (tree‐level) occupancy dynamics of three species of weevils that vary in their specialization, i.e. their relative selection of red and white oak as hosts: C. pardalis (white oak specialist), C. sulcatulus (generalist) and C. proboscideus (generalist). Contrary to expectations, the specialist exhibited greater estimated rates of occupancy than generalists. However, red oak trees occupied by the white oak specialist appeared to function as sink populations maintained by frequent colonization following local extinction. Specialists also exhibited greater relative variation in occupancy and relative abundance on their host trees among years. Generalists exhibited lower local extinction and colonization rates than the specialist. Occupancy and vital rates of weevils on a host tree increased with acorn production and were significantly influenced by neighborhood forest density. Our results suggest that across much of their range in the eastern United States acorn weevils exist in fragmented, temporally dynamic landscapes, with generalists occurring on a lower proportion of usable trees but buffered by access to more suitable patches and greater patch‐specific survival. More generally, our results demonstrate that estimates of specialization derived from occupancy data may be misleading in the absence of patch‐specific information on vital rates.

Spectral Identification of Previsual Northern Red Oak (Quercus rubra L.) Foliar Symptoms Related to Oak Decline and Red Oak Borer (Coleoptera: Cerambycidae) Attack

Abstract A severe oak decline event associated with the outbreak of an insect pest (Enaphalodes rufulus [Haldeman]) affected the Arkansas, Missouri, and Oklahoma Ozarks from the mid-1990s through 2005. Tree mortality was severe and widespread, but patchy in nature. The rugged and remote terrain of the Ozarks led to difficulty in monitoring and assessing the location, severity, and spread of declining stands. In addition, visible symptoms of decline typically occur late in the decline-disease spiral, providing little early warning and leaving few options for mitigation. In situ spectroradiometry using handheld equipment offers an affordable option for characterizing the spectral signatures of plant stress and assessing the feasibility of areawide remote sensing projects without risking a large upfront investment in imagery. Foliage from 30 northern red oak (Quercus rubra L.) trees was sampled using a handheld spectroradiometer, and analysis was conducted using machine learning techniques. Analysis of 602 reflectance and first-derivative variables provided the best prediction (90%) of field-assigned stress rankings. Eight published vegetation stress indices used as surrogate variables yielded approximately 86% accuracy in predicting the correct field-assigned stress ranking. Therefore, use of vegetation stress indices as surrogate variables may be a simpler option for analyzing future imagery of oak stress in the Ozarks while sacrificing little accuracy.

Optimal Cross-Sectional Sampling Strategy for Red Oak Borer (Coleoptera: Cerambycidae) Scars within Northern Red Oaks

Abstract We used dendrochronological techniques to develop an optimal sampling strategy for the purpose of investigating the history of red oak borer (Enaphalodes rufulus [Haldeman]) population patterns within northern red oaks (Quercus rubra L.). We cut the entire length of three northern red oak tree boles into cross-sections, sanded top and bottom surfaces of each cross-section, and dated all scars within each bole. Our goal was to devise a strategy to reduce the amount of bole sampled without compromising the data necessary to accurately estimate historical population patterns of red oak borer. When we tested four possible sampling strategies and compared them with the entire-tree data sets from which they originated, we found no statistical differences in the distribution of scar counts by year. We also assessed processing time and found that compared with sampling an entire host bole, sampling strategies that include the lower 20% or 30% of boles would reduce labor efforts by 55–63%. We suggest that development of similar sampling methods for other bark or wood-boring species may be possible if the relationship between insect life history and annual tree-ring formation, as well as the general spatial and temporal distribution of insect evidence within trees, is known.