Location of cones in the crown and along shoots of Sitka spruce (Picea sitchensis (Bong.) Carr.) and the influence of coning intensity and shoot size

1998 ◽  
Vol 28 (12) ◽  
pp. 1756-1772 ◽  
Author(s):  
G C Clarke ◽  
D C Malcolm
Keyword(s):  
Lower Order ◽  
Significant Relationship ◽  
Sitka Spruce ◽  
Picea Sitchensis ◽  
Second Order ◽  
Third Order ◽  
Rooted Cuttings ◽  
Cone Production ◽  
Shoot Size ◽  
Male Cones

The location of female cones in the crowns of rooted cuttings and mature forest-grown trees of Sitka spruce (Picea sitchensis (Bong.) Carr.) was recorded. When cones were allocated to crown sections there were clear patterns of bearing, with the majority of cones on second-order distal shoots on whorls 2 and 3. As total cone production increased, the bearing zone progressed onto more proximal shoots on upper whorls and distal shoots on lower whorls. On individual branches of clonal grafts, female cones tended to be borne on more distal shoots than male cones. Female cones, on all sample sets, tended to be borne primarily on second-order shoots and male cones, on the clonal grafts, on third-order shoots. On the clonal grafts there was a weak, though significant, relationship between the number of original buds and female, but not male, cones on a shoot. Cones were also described by position on bearing shoots. There was a tendency for the proportion of progressively more proximal cone positions to increase on lower-order shoots and vice versa. Cone position was also influenced by the dimensions of the bearing shoot independent of its position with a distal shift in cone-bearing position as shoot dimensions decreased.

scholarly journals Relation of Crown and Foliage Traits to Height Growth of Sitka Spruce

1996 ◽  
Vol 11 (3) ◽  
pp. 77-80
Author(s):  
D. L. Copes ◽  
W. H. Pawuk ◽  
W. A. Farr ◽  
R. R. Silen
Keyword(s):  
Genetic Control ◽  
Sitka Spruce ◽  
Height Growth ◽  
Picea Sitchensis ◽  
Average Height ◽  
Rooted Cuttings ◽  
Field Plots

Abstract Four crown and foliage traits of a young Sitka spruce (Picea sitchensis) stand were tested with rooted cuttings in greenhouse and field plots for possible thinning selection guidelines. Repeatability estimates of the amount of genetic control over the four traits and the relation of those traits to height growth were evaluated 5 years after rooting. Only the blue-green trait was significantly associated (P < 0.05) with height growth. Average height of cuttings selected for green foliage was 17% greater than cuttings selected for blue foliage. Under greenhouse conditions, repeatability estimates of green or blue foliage were 98% versus 66%, respectively; 72% versus 89% for trees with dense or open crowns, respectively; 65% for the comparison of upright and horizontal branches; and 75% for the comparison of long or short branches. West. J. Appl. For. 11(3):77-80.

A review of coning and seed production in Picea sitchensis

1987 ◽  
Vol 93 (1-2) ◽  
pp. 183-195 ◽  
Author(s):  
J. J. Philipson
Keyword(s):  
Seed Production ◽  
Sitka Spruce ◽  
Picea Sitchensis ◽  
Breeding Programme ◽  
Mature Trees ◽  
Physiological Mechanisms ◽  
Male And Female ◽  
Cone Production ◽  
Juvenile Phase ◽  
Similar Quantity

SynopsisSitka spruce grown from seed has a juvenile phase of about twenty years before coning commences; mature trees and grafted scions cone intermittently and produce good cone crops every three–five years. These characteristics have lengthened the breeding programme and reduced seed production in orchards. Production of male and female cones can be enhanced by treatments such as heat and drought and by application of a mixture of gibberellins A4 and A7 (GA4/7) to mature grafts. To enhance flowering consistently in container grown grafts the GA4/7 must be applied together with a cultural treatment, but with larger grafts in the field GA4/7 alone is often effective. Attempts to induce cone production in juvenile trees, however, have been less successful. Female cones initiated on field grown trees in response to inductive treatments yield seed of a similar quantity and quality to that from cones on untreated trees. The physiological mechanisms of coning, and cone induction techniques, are discussed.

scholarly journals Effects of Sitka spruce masting on phenology and demography of siskins Spinus spinus

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Euan N. Furness ◽  
Robert W. Furness
Keyword(s):  
Native Species ◽  
Late Summer ◽  
Sitka Spruce ◽  
Picea Sitchensis ◽  
Food Sources ◽  
Breeding Ecology ◽  
Cone Production ◽  
Forestry Practices ◽  
Age Ratio ◽  
Alternative Food Sources

AbstractMasting behaviour of Sitka spruce Picea sitchensis may influence Eurasian siskin Spinus spinus breeding ecology as breeding siskins specialize on spruce seeds. We caught siskins and other small passerines over 16 years using mist nets adjacent to large plantations of mature Sitka spruce. We sexed, aged, measured and weighed the birds and collected feather samples from fledglings to measure nitrogen and carbon stable isotope ratios. Siskins departed in late summer, and returned, and bred earlier in years of higher cone abundance. Nitrogen and carbon isotopes indicated that siskins fed their chicks on Sitka spruce seeds in most years, and more so in years of high cone production. More siskins were caught following heavy rainfall, when the cones had closed, encouraging the birds to seek alternative food sources. Fledglings were not heavier or larger in years with higher cone crops but were more numerous. However, the age ratio of siskins caught the following year was unaffected by cone crop. Given their reliance on Sitka spruce seeds, climate change may have a major impact on siskin numbers by altering the availability of Sitka spruce seeds, either through changes in masting patterns or cone opening, or due to climate-related changes in forestry practices. Siskins represent a valuable study system to conservation ecology, where a native species is ecologically reliant on introduced taxa.

Bulk Contributions Modulate the Sum-Frequency Generation Spectra of Interfacial Water on Model Sea-Spray Aerosols

2018 ◽  
Author(s):  
Sandeep K. Reddy ◽  
Raphael Thiraux ◽  
Bethany A. Wellen Rudd ◽  
Lu Lin ◽  
Tehseen Adel ◽  
...  
Keyword(s):  
Single Layer ◽  
Sum Frequency Generation ◽  
Second Order ◽  
Interfacial Structure ◽  
Sea Spray ◽  
Third Order ◽  
Systematic Analysis ◽  
Sum Frequency ◽  
Structure Of Water ◽  
Frequency Generation

Vibrational sum-frequency generation (vSFG) spectroscopy is used to determine the molecular structure of water at the interface of palmitic acid monolayers. Both measured and calculated spectra display speci c features due to third-order contributions to the vSFG response which are associated with nite interfacial electric potentials. We demonstrate that theoretical modeling enables to separate the third-order contributions, thus allowing for a systematic analysis of the strictly surface-sensitive, second-order component of the vSFG response. This study provides fundamental, molecular-level insights into the interfacial structure of water in a neutral surfactant system with relevance to single layer bio-membranes and environmentally relevant sea-spray aerosols. These results emphasize the key role that computer simulations can play in interpreting vSFG spectra and revealing microscopic details of water at complex interfaces, which can be difficult to extract from experiments due to the mixing of second-order, surface-sensitive and third-order, bulk-dependent contributions to the vSFG response.

Evidence for general base catalysis by protic solvents in a kinetic study of alcoholyses and hydrolyses of 1-(phenoxycarbonyl)pyridinium ions under both solvolytic and non-solvolytic conditions

2009 ◽  
Vol 74 (1) ◽  
pp. 43-55 ◽  
Author(s):  
Dennis N. Kevill ◽  
Byoung-Chun Park ◽  
Jin Burm Kyong
Keyword(s):  
Second Order ◽  
Base Catalysis ◽  
Substitution Reactions ◽  
Third Order ◽  
Methoxy Derivative ◽  
First Order ◽  
General Base ◽  
Protic Solvents ◽  
Kinetics Of ◽  
Pyridinium Ions

The kinetics of nucleophilic substitution reactions of 1-(phenoxycarbonyl)pyridinium ions, prepared with the essentially non-nucleophilic/non-basic fluoroborate as the counterion, have been studied using up to 1.60 M methanol in acetonitrile as solvent and under solvolytic conditions in 2,2,2-trifluoroethan-1-ol (TFE) and its mixtures with water. Under the non- solvolytic conditions, the parent and three pyridine-ring-substituted derivatives were studied. Both second-order (first-order in methanol) and third-order (second-order in methanol) kinetic contributions were observed. In the solvolysis studies, since solvent ionizing power values were almost constant over the range of aqueous TFE studied, a Grunwald–Winstein equation treatment of the specific rates of solvolysis for the parent and the 4-methoxy derivative could be carried out in terms of variations in solvent nucleophilicity, and an appreciable sensitivity to changes in solvent nucleophilicity was found.

Panicle, spikelet, and floret development in orchardgrass (Dactylis glomerata)

1993 ◽  
Vol 71 (4) ◽  
pp. 523-532 ◽  
Author(s):  
Joanna Fraser ◽  
Eric G. Kokko
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Unique Feature ◽  
Dactylis Glomerata ◽  
Bilateral Symmetry ◽  
Second Order ◽  
Third Order ◽  
First Order ◽  
Lateral Branches ◽  
Scanning Electron

The initial stages of panicle, spikelet, and floret development in field-grown 'Kay' orchardgrass were examined using scanning electron microscopy. Spikelets arose from a complex multilevelled sequence of initiation from branch apices. Spikelets developed indirectly in a two-tiered progression: (i) an acropetal and basipetal sequence of first order, second-order, and third-order inflorescence apices, and (ii) an acropetal development within subclusters of higher-order lateral branch inflorescence apices. The panicle had the unique feature of dorsiventrality as well as bilateral symmetry. The basal apex from first-order, second-order, or third-order apices developed on the same side of the main axis as the first-order apex. The two glumes subtending each spikelet primordium developed alternately and acropetally. Development and initiation of florets within spikelets was basipetal within the panicle, basipetal within clusters and subclusters of spikelets on lateral branches, and acropetal within spikelets. Within florets, paleas developed later than lemmas. Key words: Dactylis glomerata, cocksfoot, scanning electron microscopy, development, panicle.

Predicting the longitudinal modulus of elasticity of Sitka spruce from cellulose orientation and abundance

Holzforschung ◽  
2010 ◽  
Vol 64 (4) ◽  
Author(s):  
J. Paul McLean ◽  
Robert Evans ◽  
John R. Moore
Keyword(s):  
Bulk Density ◽  
Modulus Of Elasticity ◽  
Microfibril Angle ◽  
Sitka Spruce ◽  
Picea Sitchensis ◽  
Model Parameters ◽  
Bending Tests ◽  
Wood Stiffness ◽  
Using Data ◽  
Longitudinal Modulus

Abstract Sitka spruce (Picea sitchensis) is the most widely planted commercial tree species in the United Kingdom and Ireland. Because of the increasing use of this species for construction, the ability to predict wood stiffness is becoming more important. In this paper, a number of models are developed using data on cellulose abundance and orientation obtained from the SilviScan-3 system to predict the longitudinal modulus of elasticity (MOE) of small defect-free specimens. Longitudinal MOE was obtained from both bending tests and a sonic resonance technique. Overall, stronger relationships were found between the various measures of cellulose abundance and orientation and the dynamic MOE obtained from the sonic resonance measurements, rather than with the static MOE obtained from bending tests. There was only a moderate relationship between wood bulk density and dynamic MOE (R2=0.423), but this relationship was improved when density was divided by microfibril angle (R2=0.760). The best model for predicting both static and dynamic MOE involved the product of bulk density and the coefficient of variation in the azimuthal intensity profile (R2=0.725 and 0.862, respectively). The model parameters obtained for Sitka spruce differed from those obtained in earlier studies on Pinus radiata and Eucalyptus delegatensis, indicating that the model might require recalibration before it can be applied to different species.

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