Growth rates of the lichen Lobaria oregana as determined from sequential photographs

1977 ◽  
Vol 55 (16) ◽  
pp. 2226-2233 ◽  
Author(s):  
Frederick M. Rhoades
Keyword(s):  
Growth Rate ◽  
Pacific Northwest ◽  
Dry Weight ◽  
Similar Species ◽  
The Pacific ◽  
Lobaria Oregana ◽  
Relationship Of ◽  
Non Destructive ◽  
Epiphyte Community

The foliose lichen Lobaria oregana (Tuck.) Müll. Arg. is an important nitrogen-fixing component of the canopy epiphyte community in old-growth Douglas fir forests of the Pacific Northwest. This paper presents a non-destructive method for estimating the growth rate (grams per year) for L. oregana thalli of different weights.Photographs were made over a 2-year period of six in situ thalli. From a relationship of the photographic thallus area and weight of these and 31 other thalli, the dry weight of each of the six thalli is estimated through time. A growth rate is computed for each thallus and a relationship between growth rate and initial thallus weight is determined. Growth rate (grams per year) = exp (−0.8581 + 0.8444 (loge initial weight (grams))). The maximum radial growth rate of lobes of L. oregana determined from the photographs (9.4 mm/year) is comparable with rates for similar species.

Effects of Herbicide, Tillage, and Grass Seeding on Wild Chervil (Anthriscus sylvestris)

2011 ◽  
Vol 4 (3) ◽  
pp. 326-331 ◽  
Author(s):  
Timothy W. Miller ◽  
Danielle E. D'Auria
Keyword(s):  
Pacific Northwest ◽  
Weed Management ◽  
Dry Weight ◽  
Integrated Weed Management ◽  
Native Plant ◽  
Forage Production ◽  
Perennial Weed ◽  
Native Plant Species ◽  
Herbicide Treatment ◽  
The Pacific

AbstractWild chervil is an invasive biennial or short-lived perennial weed introduced into North America that negatively impacts forage production and degrades habitat for native plant species. A 2-yr study using prebloom mowing followed by combinations of herbicide, tillage, and grass seeding was conducted in the Pacific Northwest to identify an effective integrated weed management strategy for this species. By 2 mo after herbicide treatment (MAHT), wild chervil control with glyphosate + ammonium sulfate (AMS) and clopyralid was 83 and 73%, respectively. Tillage with or without herbicide pretreatment resulted in 92 to 98% wild chervil control at 2 MAHT, whereas herbicide without tillage gave only 45% control across all treatments. Tillage with or without subsequent grass seeding reduced wild chervil density four-fold compared to herbicide alone at 9 MAHT. Herbicide + tillage + grass seeding resulted in similar wild chervil cover (1 to 5% cover) as herbicide + tillage (1 to 6% cover) without subsequent grass seeding. Wild chervil biomass at 1 yr after herbicide treatment (YAHT) was reduced to 487 kg ha−1 (439 lb ac−1) with herbicide + tillage compared to 4,256 kg ha−1 for herbicide treatment alone. Herbicide + tillage + grass seeding increased grass dry weight at 1 YAHT from 201 kg ha−1 for herbicide + tillage to 1,575 kg ha−1, compared to 351 kg ha−1 in herbicide-only plots.

Regional Differences in Otolith Morphology of the Deep Slope Red Snapper Etelis carbunculus

1992 ◽  
Vol 49 (4) ◽  
pp. 795-804 ◽  
Author(s):  
M. Kimberly Smith
Keyword(s):  
Growth Rate ◽  
Regional Differences ◽  
Maximum Size ◽  
Dry Weight ◽  
French Polynesia ◽  
Red Snapper ◽  
Fish Length ◽  
Otolith Shape ◽  
The Pacific ◽  
Wide Range

Sagittal otoliths from four populations of the Pacific deep slope red snapper Etelis carbunculus Cuvier were compared using Fourier descriptors and other shape indices, linear proportions, and dry weight. Otoliths from Hawaii, Vanuatu, Fiji and French Polynesia and a small number from the Commonwealth of the Northern Marianas Islands (NMI) were examined. Regional shape and weight characteristics were distinguishable, despite the wide range of individual variation and limited available size range from some regions. Size-specific differences in otolith shape were found for the four regions for which a sufficient sample was available. Otoliths from Hawaii, French Polynesia, and NMI showed a significant shape affinity. Otoliths from Fiji and Vanuatu were similarly shaped and were distinct from those from the other three regions. Interregional otolith shape affinities for the stocks examined parallel similarities in maximum size and growth rate from the literature, suggesting that growth rate may influence otolith shape. Observed trends in otolith weight as a function of fish length support growth-related regional differences in otolith shape.

scholarly journals The Effect of Hexazinone, Sulfometuron, Metsulfuron, and Atrazine on the Germination Success of Selected Ceanothus and Rubus Species

2002 ◽  
Vol 17 (4) ◽  
pp. 194-201
Author(s):  
Robin Rose ◽  
J. Scott Ketchum
Keyword(s):  
Pacific Northwest ◽  
Dry Weight ◽  
Efficacy Trial ◽  
Herbicide Application ◽  
The Pacific ◽  
Germination Success ◽  
Rubus Species ◽  
Herbaceous Weed Control ◽  
The Impact ◽  
Germination And Growth

Abstract This study documents the impact pre-emergent forestry herbicides have on germination of some selected seral woody competitors in the Pacific Northwest. Four commonly used pre-emergent soil-active herbicides (hexazinone, sulfometuron, metsulfuron, and atrazine) typically used for herbaceous weed control were applied at six rates over stratified seed of Ceanothus velutinus (CEVE) and Ceanothus integerrimus (CEIN) in a greenhouse efficacy trial. In addition, hexazinone and sulfometuron were applied over stratified Rubus ursinus (RUUR) and Rubus parviflorus (RUPA) seed and sulfometuron over stratified seed of Rubus spectabilis (RUSP) at the same six rates. Numbers of seed to successfully germinate and develop true leaves were counted over a 9 wk period immediately following herbicide application. The hexazinone treatments reduced germination and growth of CEVE, CEIN, and RUPA. The RUUR species was tolerant of the hexazinone herbicide at low rates but at higher rates was strongly affected. The sulfometuron treatments had less effect on survival probability than hexazinone but strongly reduced the average dry weight of plantlets of all species. Seedling dry weight decreased with increasing rate of both metsulfuron and atrazine. Increasing the metsulfuron rate reduced the probability for CEVE seedlings to survive but not CEIN. Finally, atrazine sharply reduced the plantlet survival and reduced dry weight of both CEVE and CEIN even at low rates.West. J. Appl. For. 17(4):194–201.

Biomass and mineral capital of epiphytes in an Acer macrophyllum community of a temperate moist coniferous forest, Olympic Peninsula, Washington State

1984 ◽  
Vol 62 (11) ◽  
pp. 2223-2228 ◽  
Author(s):  
Nalini M. Nadkarni
Keyword(s):  
Pacific Northwest ◽  
Coniferous Forest ◽  
Dry Weight ◽  
Nutrient Concentrations ◽  
Acer Macrophyllum ◽  
River Terraces ◽  
Host Trees ◽  
Olympic Mountains ◽  
Seasonal Basis ◽  
Epiphyte Community

The epiphyte community of a Pacific northwest temperate rain forest makes up a conspicuous portion of the canopy, especially on the Acer macrophyllum trees that grow along river terraces of wet western slopes of the Olympic Mountains. Destructive sampling methods were used to assess the composition, biomass, and nutrient concentrations of live and dead epiphytes on representative host trees to determine the mineral capital contained in the epiphytic components of the standing vegetation. Average epiphyte standing crop on mature Acer macrophyllum trees is 35.5 kg. The nutrient capital (grams) is N, 370; P, 44; K, 145; Ca, 270; Mg, 50; and Na, 9. Although epiphyte biomass constitutes less than 2% of total aboveground ecosystem dry weight, it is equivalent to nearly four times the foliar biomass of host trees on a single-tree basis. Epiphytes are efficient at garnering nutrients from atmospheric sources and retaining them within the biotic portion of the ecosystem. They supplement the nutrient-gathering apparatus of host trees and buffer nutrient pulses on a short-term and on a seasonal basis.

scholarly journals In situ Root Phenotypes of Cotton Seedlings Under Phosphorus Stress Revealed Through RhizoPot

2021 ◽  
Vol 12 ◽  
Author(s):  
Zichen Zhang ◽  
Lingxiao Zhu ◽  
Dongxiao Li ◽  
Nan Wang ◽  
Hongchun Sun ◽  
...  
Keyword(s):  
Growth Rate ◽  
Root Length ◽  
Root Length Density ◽  
Root Hairs ◽  
Specific Root Length ◽  
Dry Weight ◽  
P Deficiency ◽  
Branch Density ◽  
P Absorption

Phosphorus (P) deficiency is a common challenge in crop production because of its poor mobility through the soil. The root system plays a significant role in P absorption from the soil and is the initial indicator of low P levels. However, the phenotypic dynamics and longevity of cotton roots under P stress remain unknown. In this study, RhizoPot, an improvised in situ root observation device, was used to monitor the dynamics of root phenotypes of cotton seedlings under P-deficient (PD) and P-replete (PR) conditions. Low P stress reduced P absorption and accumulation in the roots, leading to low dry weight accumulation. Cotton seedlings responded to low P stress by increasing the number of lateral roots, specific root length, branch density, root length density, and length of root hairs. Additionally, the life span of root hairs was prolonged. Low P stress also reduced the average diameter of roots, promoted root extension, expanded the root coverage area, and increased the range of P acquisition. Principal component analysis revealed that the net root growth rate, root length density, root dry weight, P absorption efficiency, average root hair length, and taproot daily growth significantly influenced the cotton root architecture. Collectively, these results show that low P stress reduces the net growth rate of cotton seedling roots and restricts plant growth. Plants respond to P deficiency by extending the life span of root hairs and increasing specific root length and lateral root branch density. This change in root system architecture improves the adaptability of plants to low P conditions. The findings of this study may guide the selection of cotton varieties with efficient P utilization.

Systematic relationship of parapatric tree squirrel species (Tamiasciurus) in the Pacific Northwest

1982 ◽  
Vol 60 (9) ◽  
pp. 2149-2156 ◽  
Author(s):  
Stephen L. Lindsay
Keyword(s):  
Pacific Northwest ◽  
Taxonomic Distance ◽  
The Pacific ◽  
Tree Squirrels ◽  
History Of ◽  
Tree Squirrel ◽  
Components Analysis ◽  
Relationship Of ◽  
Two Populations ◽  
Pelage Coloration

Phenetic analysis of 20 cranial characters was used in an evaluation of the systematics of two Pacific Northwest tree squirrels, Tamiasciurus douglasii and T. hudsonicus. Although these species are predominantly allopatric, there exist at least three zones of sympatry along a parapatric border in British Columbia, Washington, and Oregon. Two populations of supposedly hybrid squirrels have been described, and these were evaluated in relation to allopatric populations of both species from throughout the area. Principal components analysis, clustering of taxonomic distance coefficients, and discriminant analysis showed a strong morphologic distinctness between the two species. These analyses also consistently placed "hybrid" specimens with one species or the other and gave no indication of intergradation. The Pleistocene glacial history of the Pacific Northwest is used to explain the divergence of the two species as well as the formation of the parapatric species border. In addition, postglacial character convergence in pelage coloration and squirrel size in forest areas allowing noncompetitive coexistence is used to explain the apparent hybrids and to account for the disjunct Vancouver Island distribution of T. douglasii-like T. hudsonicus. It is concluded that with the lack of hybridization and the presence of character convergence in zones of sympatry, reproductive isolation between T. douglasii and T. hudsonicus is complete.

Moisture Content of Baled Forest and Urban Woody Biomass during Long-term Open Storage

2018 ◽  
Vol 34 (1) ◽  
pp. 225-230
Author(s):  
James H Dooley ◽  
Matthew J Wamsley ◽  
Jason M Perry
Keyword(s):  
Moisture Content ◽  
Pacific Northwest ◽  
Initial Moisture Content ◽  
Woody Biomass ◽  
Dry Weight ◽  
The United States ◽  
Long Term Storage ◽  
The Pacific ◽  
Early Fall

Abstract. This article describes how the moisture content of baled woody biomass varied during long-term open-air storage under conditions in the Pacific Northwest region of the United States. Large rectangular bales of forest and urban biomass were produced beginning in August 2015 and periodically until June 2016. Weights were measured approximately monthly until the entire lot of bales was ground into fuel in December 2016. Because it was impractical to non-destructively obtain moisture content samples during the study, final moisture content was measured from the ground material. Estimated temporal moisture contents were back-calculated from the final dry weight and moisture content of bales. All bales dried considerably during the spring and summer months, achieving a minimum moisture content in the early fall of 15 to 29% (wb). Minimum early fall moisture content had no correlation with the initial moisture content at time of baling. The ending moisture content in December 2016 ranged from 44% to 57% (wb), with a mean moisture content of 53% (wb). Ending moisture content had no correlation with initial moisture content at the time of baling, but appeared to be related to the amount of fine versus coarse woody material in the bales. Bales of forest and urban woody biomass proved to be structurally stable during long-term storage to enable handling and final transport to a centralized grinding location. Keywords: Density, Logging, Baling, Bioenergy, Biofuel, Bundling, Forest operations, Forestry, MC, Seasonality, Transport, Woody biomass.

The lichens and lichenicolous fungi of Haida Gwaii (Queen Charlotte Islands), British Columbia, Canada. 5. A new species of Lecanora from shoreline rocksThis paper is one of a selection of papers published as part of the special Schofield Gedenkschrift.

Botany ◽  
2010 ◽  
Vol 88 (4) ◽  
pp. 352-358 ◽  
Author(s):  
Irwin M. Brodo
Keyword(s):  
British Columbia ◽  
New Species ◽  
Pacific Northwest ◽  
Similar Species ◽  
Haida Gwaii ◽  
Queen Charlotte Islands ◽  
The Pacific ◽  
A New Species ◽  
Selection Of ◽  
Northeast Coast

A species of Lecanora in the L. dispersa group, with a well-developed pale thallus and a granular epihymenium, resembling L. albescens , is found exclusively on shoreline rocks and appears to be new. It is described as Lecanora schofieldii  sp. nov., found mainly in the Pacific Northwest, but also rarely on the northeast coast. Its distinctions from similar species on shoreline rocks are given, together with a key for their identification. The first western record of L. xylophila from rocks is given.

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