Single Spruce Research Articles

Spear study misses the point: a critique of the Ennos and Chan fire-hardening study, concerning wood material representation in archaeological finds and generalized conclusions.

Spear study misses the point: a critique of the Ennos and Chan fire-hardening study, concerning wood material representation in archaeological finds and generalized conclusions.

Arthropod infestation sites and induced defence can be traced by emission from single spruce needles

Emissions of defence chemicals from Norway spruce seedlings can be induced by feeding arthropods or by exogenous hormonal application. Some defence chemicals may attract or repel associated arthropods. The aim of this study was to show that it is possible to detect and collect stress-induced volatiles from micro sites, such as at the scale of a single needle, in vivo by using SPME. Methyl jasmonate application on the stem of Norway spruce seedlings induced emission of (E)-β-farnesene only from the needles closest to the application site. Emissions of (E)-β-farnesene, (E,E)-α-farnesene and (E)-α-bisabolene were only detected from needles infested by the spider mite Oligonychus ununguis. The total volatile amount detected by SPME-GC-MS reached a considerable mass of 14 ng/needle/24 h, suggesting that emission from damaged and stressed conifers might have a larger impact on the macro climate than previously estimated.

Self-Portrait as Pyrocumulonimbus, and: Driving Up-Canyon With My Two Teen Sons

Self-Portrait as Pyrocumulonimbus, and: Driving Up-Canyon With My Two Teen Sons Lisa Fay Coutley (bio) Self-Portrait as Pyrocumulonimbus Don't ask me why men want from this peculiar pulse, skipping cul-de-sacs & riverbeds. I eat like a woman ravenous until the forest is a field standing black with javelins. I catapultinto clear sky. Because God loosed me from that better wound, braiding anger up my spine, & between ground & cloud bellowed the flame, they crave. They say destruction as if they don't want to follow. Don't study how I hoverabove them, cracking my ribs apart, peeling lightning from my thighs. They pray for my unruly heart, may it be their weapon. They misunderstand. My desire is air, threading vengeance into the dress I'd wear if I wokeeach morning in a bed half slept in, but I don't sleep. I wander. I err. I lunge into ductwork & become the bedroom, the porch swing, the yellow grass around the concrete deer. I keep hoping for a day when burn won't breedash, & we can return home, devoured [End Page 42] by hunger neither mine nor theirs, but fear unleashed refuses the chain. The fruit is my miracle is my palm is my water effacing the blaze. I would surrender my mouth to rain if they didn't beg from methe bite-bruise on both shoulders again, again. [End Page 43] Driving Up-Canyon With My Two Teen Sons Lisa Fay Coutley or Boys I & II as I've come to call them (or swear at them) this year, laying the fencework of broken bottles all around me, even now, as we push faster up a blinding canyon road. Look, boys, here even crag reaches straight for the sun (& I can't help but tell them we each want to burn); look at how the aspens stand together from one, long root, but they'll never touch each other above ground; look at the single spruce that grew back-against-a-cliff-wall, facing only road (as I'm speeding up a lane that snakes to nowhere I can see). This, you'll never understand. Like the way I arrange sunflowers on the coffee table in our new home. Have you noticed how they reach for sun or soil, where there's only ceiling, only vase. This, kids, is the year we'll write our history of black ice & snow. Here, each of you hold a wiper blade, & I'll accelerate, eyes closed. [End Page 44] Lisa Fay Coutley Lisa Fay Coutley is the author of In the Carnival of Breathing, winner of the Black River Chapbook Competition (Black Lawrence Press, 2011) and Back-Talk, winner of the ROOMS Chapbook Contest (Articles Press, 2010). A doctoral fellow and poetry editor for Quarterly West at the University of Utah, she has been awarded scholarships to the Bread Loaf and Sewanee Writers' Conferences, an Academy of American Poets' 2012 Larry Levis Prize, chosen by Dana Levin, and her recent poems appear in Seneca Review, Third Coast, The Journal, Hayden's Ferry Review, Best New Poets, and on Verse Daily. Copyright © 2013 University of Wisconsin Board of Regents

Modelling infestation risk of Norway spruce by Ips typographus (L.) in the Lower Saxon Harz Mountains (Germany)

Norway spruce ( Picea abies (L.) Karst.) is economically the most important European tree species but is particularly prone to insect infestation calamities. Among the biotic risks threatening Norway spruce in Europe the spruce bark beetle Ips typographus (L.) is the most significant pest. On the basis of projected climate-change scenarios higher temperatures and longer growing seasons will probably lead to even more frequent and serious outbreaks of this pest as a result of more generations per year. At the same time periods of drought may become more frequent and be of longer duration resulting in a physiological weakening of Norway spruce. Hence, it is necessary to develop concepts that can be used in long term silvicultural planning to minimize the risk of bark beetle infestations until trees reach maturity. For an adaptation of forest management it is necessary to identify and quantify risks at the level of silvicultural planning units. Therefore, we developed, a mixed binary linear regression model, which describes the effects of different stand and site variables on the infestation risk that bark beetles exert on spruce stands in the Harz Mountains. The relevant data are based on a decade of detailed forest booking records carried out by the Lower Saxony State Forest in the western Harz Mountains and cover 12,085 individual registrations on 4352 stands. In the model, the stand parameters age and proportion of spruce, and site parameters available water capacity, thermal sum and the Topex-to-Distance Index have significant effects on the infestation risk. It is presumed that the impact of various but unknown silvicultural measures and pest control tactics in managed forests can be quantified by random effects on the forest sub-district level. When applying our model it is possible to assign expected risk levels to single spruce stands. Thereby, we can add a biotic risk component to site-oriented silviculture. Thus, a mapped ranking of spruce stands pertaining to bark beetle infestation risk can be provided. In addition, specific silvicultural management strategies such as shortening of rotation periods or an admixture of broadleaved tree species can be derived from the model’s predictions.

The Individual Tree Crown Approach Applied to Ikonos Images of a Coniferous Plantation Area

In forestry, the availability of high spatial resolution (� 1 m/pixel) imagery from new earth observation satellites like Ikonos favours a shift in the image analysis paradigm from a pixel-based approach towards one dealing directly with the essential structuring element of such images: the individual tree crown (ITC). This paper gives an initial assessment of the effects of 1 m and 4 m/pixel spatial resolutions (panchromatic and multispectral bands, respectively) on the detection, delineation, and classification of the individual tree crowns seen in Ikonos images. Winter and summer Ikonos images of the Hudson plantation of the Petawawa Research Forest, Ontario, Canada were analyzed. The panchromatic images were resampled to 0.5 m/pixel and then smoothed using a 3 � 3 kernel mean filter. A valleyfollowing algorithm and rule-based isolation module were applied to delineate the individual tree crowns. Local maxima within a moving 3 � 3 window (i.e., Tree Tops) were also extracted from the smoothed images for comparison. Crown delineation and detection results were summarised and compared with field tree counts. Overall, the ITC delineation and the local maxima approaches led to tree counts that were on average 15 percent off for both seasons. Visual inspection reveals delineation of clusters of two or three crowns as a common source of error. Crown-based species spectral signatures were generated for six classes representing conifer species, plus a hardwood class and a shrub class. After the ITC-based classification, classification accuracy was ascertained using separate test areas of known species. The overall accuracy was 59 percent. Important confusion exists between red and white spruces, and mature versus immature white pines, but post-classification regroupings into single spruce and white pine classes led to an overall accuracy of 67 percent.

Polarized infrared microspectroscopy of single spruce fibers: Hydrogen bonding in wood polymers

We studied wood polymers in their native composite structure using mechanically isolated single spruce (Picea abies [L.] Karst.) fibers. Dichroic infrared spectra of fibers placed in a custom-built microfluidic cuvette were acquired in air, in liquid (heavy) water, and in liquid dimethylacetamide using a novel combination of synchrotron-based Fourier transform infrared microspectroscopy with polarization modulation. Differences were observed in the O-H stretching frequency region of the spruce spectra upon changing the ambient conditions. Analysis of these spectral variations provides information on hydrogen bonding, orientation, and accessibility of structural units of the wood polymers in the spruce cell walls. Our in situ approach contributes to a further understanding of the structural details of wood polymers in their native setting.

Anthropogenically-triggered iron pan formation in some Irish soils over various time spans

Podzolisation, with iron transport and deposition as coloured Bs or Bh horizons, is the fate of acid or decalcified, free-draining mineral soils in Ireland's cool temperate, humid climate. A second generation of iron accumulation, mainly in the form of thin seams (pans, placic horizons) has been studied at several locations in Ireland. These seams generally occur within a former cultivated horizon and within 20–25 cm of the current surface. The time span over which the iron pans developed ranges from a few decades to four or five centuries and invariably involved a change in land-use. The trigger for the new accumulation is a change in Eh/pH relations and/or acid/base conditions. Examples include (1) sudden and massive loading of a parkland pasture with peat debris in the 1950s, (2) acid litter from a single spruce crop (ca. 50 years) in a reclaimed podzol topsoil, (3) slow accumulation of peat debris over a number of decades in a peat fuel storage area, started about 100 years ago, (4) invasion of land abandoned ca. 1850 by heather and other acidophilic species and (5) run down of soil fertility and structure by grazing without amendments (pedogenic age, four to five centuries). The morphological and chemical characteristics of these soils show that where free iron is present in a horizon, any land-use change that establishes a pH or Eh/pH gradient is likely to initiate diffusion gradients and the local accumulation of iron oxides, irrespective of topographic position. This study investigates the effect of organic matter on iron accumulation and on the development of the second-generation eluvial/illuvial horizon sequence as affected by anthropogenic activities.

Formulation selection, and investigation of azadirachtin-A persistence in some terrestrial and aquatic components of a forest environment

Five commercial formulations of azadirachtin-A (AZ-A) Margosan-O®, Azatin-EC®, Neem-EC®, RH-9999 and Neemix® 4.5, were investigated for their volatilization and washoff potential in laboratory studies. Prior to the investigation, RH-9999 (a wettable powder) was mixed with water to provide an end-use formulation containing 35.6 g AZ-A kg -1 , while the remaining four formulations were investigated without dilution. Volatilization and washoff of AZ-A occurred more from white spruce foliage than from wax-coated glass plates. Neem-EC provided the lowest amount of loss, whereas Margosan-O provided the highest. Physical properties and atomization behaviour of the five formulations indicated that Azatin-EC was highly viscous and caused phase separation in droplets collected on glass plates after atomization in a rotary atomizer. RH-9999, despite its low viscosity, caused phase separation in droplets because of the heterogeneity of the wettable powder formulation. Based on the minimum loss of AZ-A due to volatilization and washoff from spruce foliage, and on the minimum potential for phase separation in droplets after atomization in a rotary atomizer, Neem-EC was considered to be the most appropriate choice for use in field studies to investigate environmental persistence and fate of AZ-A in terrestrial and aquatic matrices of a forest ecosystem. The Neem-EC formulation was sprayed at 40 and 80 g AI ha -1 over single spruce trees and on litter and soil plots selected in a mixed-wood boreal forest in Ontario, Canada. In addition, outdoor aquaria containing stream water and sediment were also fortified with the formulation at 400 and 800 g AI ha -1 . Persistence of AZ-A was evaluated using one-year-old spruce needles, current-year shoots, spruce bark, litter, soil, stream water and sediment. The duration of persistence varied from 3 to 6 days in terrestrial matrices, whereas it ranged from 8 to 13 days in water, and 2 to 3 days in sediment. The half-life (DT 50 ) values ranged from 10.7 h (for soil) to 71.6 h (for spruce bark) at the lower dosage rate, and from 18.8 h (for litter) to 76.2 h (for bark) at the higher dosage rate. The DT 50 value for stream water was about 35 h regardless of the dosage rate applied. The data indicated that AZ-A was appreciably labile and short-lived in different forestry matrices, with low DT 50 values.

Single tree genetic linkage mapping in conifers using haploid DNA from megagametophytes.

We report a unique application of the Random Amplified Polymorphic DNA (RAPD) technique for genetic linkage mapping of a single spruce tree using haploid DNA from megagametophyte tissue of individual seeds. Sixty-one segregating loci were analysed for reproducibility, inheritance and linkage. Forty-seven of the 61 markers were distributed into 12 linkage groups and covered 873.8 cM. The 14 markers not associated with any linkage group should be assigned to linkage groups as more markers are added to the map. This new approach quickly provides molecular genetic markers that are simple to evaluate for constructing genetic linkage maps and for other related genetic studies in forest tree species.

Microwave transmission, a new tool in forest hydrological research

After several decades of interception studies, there are still considerable gaps in the understanding of wet-canopy evaporation. Model development is being obstructed by the lack of techniques for the measurement of state and rate variables which have to be quantified for model validation. The applicability of microwave attenuation measurements for the determination of canopy wetness is examined. The attenuation caused by a single spruce fir in the laboratory and the vertical attenuation profiles of a Douglas fir stand were measured under dry and wet conditions. The results indicate an instant increase of the attenuation upon wetting and a decrease owing to drip and evaporation after rainfall ceased. From the results, conclusions have been drawn on the design of instrumentation for an optimized measuring system which is suitable for unattended automated scanning of canopy water storage. This system has been calibrated, using vertically integrated microwave attenuation profiles and canopy water budgets from precipitation and throughfall measurements. This system will be used for a forest hydrological study in the framework of the Dutch ACIFORN project, a research project on the effect of atmospheric deposition on Douglas fir vitality.

Younger dryas climatic reversal in northeastern USA? AMS ages for an old problem

Late-glacial macrofossils from a 10-m core from Alpine Swamp, New Jersey, were radiocarbon dated using accelerator mass spectrometry (AMS). The arrival of the first trees to the area following deglaciation is indicated by maximum percentages of spruce pollen and a date of 12,290 ± 440 yr B.P. on a single spruce needle. Subsequent spread of deciduous hardwoods was followed by the expansion of boreal taxa, including spruce ( Picea), fir ( Abies), larch ( Larix laricina), paper birch ( Betula papyrifera), and alder ( Alnus). Three AMS dates on paper birch seeds and a spruce needle during this boreal expansion indicate that it took place between 11,000 and 10,000 yr B.P. The timing of this vegetational shift and its correlation with late-glacial pollen stratigraphy from many sites in southern New England indicate that a climatic reversal correlative with the Younger Dryas characterized the North Atlantic seaboard of the United States.

A comparative evaluation of dislodgable and penetrated residues, and persistence characteristics of aminocarb and fenitrothion, following application of several formulations onto conifer trees

Abstract A comparative evaluation of dislodgable and penetrated residues, and persistence patterns of aminocarb and fenitrothion, was made using several formulations containing diluents with different physi‐cochemical characteristics. Spray was applied onto single spruce trees in a tree farm in Shawville, Quebec, using a dosage rate of 90 g AI (active ingredient)/ha for aminocarb and 340 g AI/ha for fenitrothion. Droplet and deposit data were also obtained simultaneously on sampling units. The data indicated that, with both insecticides, low‐volatility diluents provided larger droplets, higher deposits and foliar residues than high‐volatility diluents. The rate of dissipation and persistence patterns of the dislodagable and penetrated residues were also related to the type of diluents used. However, the penetrated residues dissipated slower than the dis‐lodgable residues, indicating their tendency to resist environmental loss by volatilization, photodegradation and leaching by rain. The amounts of dislodgable residues obtained were related to the dosage rate applied, i.e., those of aminocarb were much lower than those of fenitrothion, whereas the penetrated residues were very similar for both insecticides, suggesting a maximum limit beyond which little increase can occur by increasing the dosage rate of application.