ESTIMATING EPIDEMIC POPULATIONS OF THE LESSER MAPLE SPANWORM (LEPIDOPTERA: GEOMETRIDAE)

1979 ◽  
Vol 111 (2) ◽  
pp. 189-200
Author(s):  
W. J. A. Volney
Keyword(s):  
Unit Area ◽  
Larval Density ◽  
Acer Rubrum ◽  
Strong Relationship ◽  
Stem Diameter ◽  
Sampling Techniques ◽  
Red Maple ◽  
The Mean ◽  
The Relationship ◽  
Number Of Shoots

AbstractThe distribution of lesser maple spanworm, Itame pustularia (Gn.) (Lepidoptera: Geometridae) larvae in red maple, Acer rubrum L., crowns and of pupae under these trees, and the relationship between the number of shoots on these trees and several easily-measured tree dimensions are used to design sampling techniques for estimating the mean number of larvae per shoot and the mean number of pupae per unit area in epidemic populations. An estimate of the total number of larvae per unit area is obtained from the product of larval density and the number of shoots per unit area. Some indication of how this latter estimate might be obtained is discussed. Because of the strong relationship between stem diameter and the number of shoots on a tree, a double sample procedure can be designed based on shoot counts from a relatively small number of trees. Auxiliary measurements on a large number of trees can improve the precision of the estimate.

scholarly journals Relationship between Growth and Wood properties in Agathis sp. Planted in Indonesia

2017 ◽  
Vol 3 (1) ◽  
pp. 1-5
Author(s):  
Futoshi Ishiguri ◽  
Kazuko Makino ◽  
Imam Wahyudi ◽  
Jun Tanabe ◽  
Yuya Takashima ◽  
...  
Keyword(s):  
Wood Quality ◽  
Basic Density ◽  
Tree Breeding ◽  
Wood Properties ◽  
Stem Diameter ◽  
Breeding Programs ◽  
Significant Difference ◽  
Pilodyn Penetration ◽  
The Mean ◽  
The Relationship

The present study clarified the relationship between the growth and wood properties of 54-year-old Agathis sp. trees planted in Indonesia. Stem diameter, pilodyn penetration, and stress-wave velocity (SWV) were measured for all trees (35 trees) in a plot (30  30 m) located almost at the center of a stand. Based on the mean stem diameter, 10 standard trees in a plot were selected for measuring the basic density (BD) and compressive strength parallel to grain (CS). Core samples (5 mm in diameter) were collected from the 10 selected trees to determine BD and CS. The mean stem diameter, pilodyn penetration and SWV in the plot were 40.2  11.3 cm, 23.4  2.1 cm, and 3.85  0.43 km/s, respectively. No  significant correlation coefficeint (r = -0.327, no significance at 5% level) was obtained between stem diameter and SWV. The mean BD and CS in the 10 trees were 0.42  0.03 g/cm3  and 28.1  2.7 MPa, respectively. A significant positive  correlation was observed between BD and CS. Analysis of variance (ANOVA) revealed a significant difference between BD and CS values of the 10 trees, indicating that wood properties may differ among trees with the same standard growth in a stand. From these results, we concluded that wood quality improvement in this species could be achieved by selecting  trees with high density and strength in tree breeding programs.

scholarly journals A Study on the Relationship Between Mean Years of Schooling, Literacy Skills Level of the Countries, and Their Level of Democratic Development

2019 ◽  
Vol 9 (1) ◽  
pp. 145
Author(s):  
Ayşe Ottekin Demirbolat
Keyword(s):  
Informal Education ◽  
Strong Relationship ◽  
Literacy Skills ◽  
Departure Point ◽  
Democratic Development ◽  
Medium Level ◽  
The Mean ◽  
Development Levels ◽  
The Relationship ◽  
Years Of Schooling

This study’s objective is to examine the relationship between the mean years of schooling, level of adult literacyskills, and democratic development levels. The study was designed as a relational survey model. The analyticsemployed is the path analysis, which tests the existence of causal relationship between the variables. The statisticalanalysis indicates that a significant and strong relationship exists between the mean years of schooling and adultliteracy skills and further that a significant, medium level, relationship is present between the countries’ adult literacyskills and their democratic development levels. Moreover, literacy skills create a significant mediation impact on therelationship between the mean years of schooling and democratic development level. Also significant is the indirectimpact of the nations’ mean years of schooling on their democratic development levels. Countries seeking to sustainand protect participative and deep democracy may need to review their formal and informal education policies.Therefore, it may be especially necessary to attach greater importance to cognitive-verbal processes in formaleducation institutions as a departure point of action.

The effects of breed, crossbreeding and other factors on variation in fleece and skin traits

1980 ◽  
Vol 30 (3) ◽  
pp. 417-429 ◽  
Author(s):  
J. A. Woolliams ◽  
G. Wiener
Keyword(s):  
Unit Area ◽  
Fibre Diameter ◽  
Fibre Length ◽  
Live Weight ◽  
Strong Relationship ◽  
Average Fibre Diameter ◽  
Wide Range ◽  
Average Fibre ◽  
Fleece Weight ◽  
The Relationship

ABSTRACTBreed and crossbreeding significantly affected variation in 10 fleece, follicle density and fibre diameter traits in 12-week-old lambs. The breeds involved were the Scottish Blackface, South Country Cheviot, Welsh Mountain, Lincoln Longwool, Southdown and Tasmanian Merino, but the last only by rams.The Southdown came closest to the Merino in affecting density and diameter traits although the Merino crosses remained clearly distinguishable by their high follicle density. The Lincoln and Blackface crosses were notable for their long fibres and the Blackface crosses also had the least dense follicle and coarsest primary fibres. The coarsest secondary fibres were from Lincoln and Cheviot crosses. Heterosis estimates were obtained for crosses involving the Blackface, Cheviot, Welsh and Lincoln breeds. Significant heterosis was present in a wide range of traits but was not apparent in all crosses. Maternal differences were evident for many of the traits but with density these differences were apparently related to maternal effects on live weight of the lamb. The sex of the lamb, its birth type and rearing and its 12-week live weight significantly affected many of the traits.Among breeds and crosses a strong relationship was found between fibre density and average fibre diameter. The relationship suggested that breed variation in total fibre area per unit area of skin was small compared with the breed variation in its components. Fleece weight per unit area was most closely related to mean fibre length.

scholarly journals Production and Rooting of Shoots Generated from Dormant Stem Sections of Maple Species

HortScience ◽  
1997 ◽  
Vol 32 (7) ◽  
pp. 1274-1275 ◽  
Author(s):  
Paul H. Henry ◽  
John E. Preece
Keyword(s):  
Acer Saccharum ◽  
Sugar Maple ◽  
Acer Rubrum ◽  
Adventitious Rooting ◽  
Study Data ◽  
Stem Cuttings ◽  
Red Maple ◽  
Significant Variability ◽  
Rooting Response ◽  
Number Of Shoots

Vegetative shoots were forced in the greenhouse from excised stem (branch) sections of dormant Japanese maple (Acer palmatum Thunb.), red maple (Acer rubrum L.), and sugar maple (Acer saccharum Marsh.). Softwood shoots generated in this way were used as stem cuttings in a subsequent adventitious rooting study. Data indicate that maple shoots can be forced using this technique, but that both the percentage of stem sections forming shoots and the number of shoots produced are highly variable among both species and clones. Whereas Japanese and red maple formed shoots on >50% of stem sections, shoots were generated on only 20% of sugar maple stem sections. Significant variability was also observed in rooting response, with red maple shoots rooting at much higher percentages (60%) than either Japanese maple (26%) or sugar maple (15%).

scholarly journals Foliar Chlorosis in Field-Grown Red Maples

HortScience ◽  
2006 ◽  
Vol 41 (5) ◽  
pp. 1347-1350 ◽  
Author(s):  
James Altland
Keyword(s):  
Tissue Sample ◽  
Acer Rubrum ◽  
Stem Diameter ◽  
Red Maple ◽  
Essential Nutrients ◽  
Leaf Chlorophyll ◽  
Nursery Production ◽  
Quality Rating ◽  
Foliar Tissue ◽  
Highly Correlated

Franksred red maple (Acer rubrum `Franksred') trees were sampled from nursery fields in 2003 and 2004 to determine the cause of a common foliar chlorosis. Plots in 21 and 39 different nurseries were identified in 2003 and 2004, respectively. A single plot from each nursery was sampled in June of each year, whereas two to four plots per nursery were sampled in September. Each plot consisted of 20 consecutive trees in a single row. From each plot, a foliar tissue sample was analyzed for the complete range of essential nutrients. Plant height, stem diameter, leaf chlorophyll content, and a subjective plant quality rating were also recorded. From each plot, a soil sample was collected and analyzed for pH, EC, organic matter, and a range of essential nutrients. The foliar chlorosis was determined to be incited by manganese (Mn) deficiency. Tissue Mn was highly correlated with soil pH. Chlorotic plants were smaller with less stem diameter than nonchlorotic plants. Sufficiency ranges for tissue and soil tests were determined and are provided for red maple nursery production.

scholarly journals Biostimulants and Soil Amendments Affect Two-year Posttransplant Growth of Red Maple and Washington Hawthorn

HortScience ◽  
1998 ◽  
Vol 33 (5) ◽  
pp. 819-822 ◽  
Author(s):  
Matt Kelting ◽  
J. Roger Harris ◽  
Jody Fanelli ◽  
Bonnie Appleton
Keyword(s):  
Root Length ◽  
Liquid Mixture ◽  
Acer Rubrum ◽  
Dry Mass ◽  
Stem Diameter ◽  
Red Maple ◽  
Yard Waste ◽  
Intermediate Metabolites ◽  
Treatment Interaction ◽  
Kelp Extract

Humate-based products have been aggressively marketed as biostimulants that increase plant growth. Little data are available on their effect on tree establishment or their interaction with fertilizer and irrigation regimes. This experiment tested several types of biostimulants on posttransplant growth of Acer rubrum L. (red maple) and Crataegus phaenopyrum (Blume) Hara (Washington hawthorn) trees, both with and without irrigation and fertilization. Soil treatments were applied at planting as: 1) control (native backfill only); 2) compost (native backfill + yard-waste compost); 3) peat (native backfill + Canadian sphagnum peat); 4) granular humate, 100 g/tree; 5) granular humate, 200 g/tree; and 6) liquid humate +, a proprietary liquid mixture of humate, kelp extract, thiamine, and intermediate “metabolites.” Irrigation regime × soil treatment interaction was significant for red maple, but soil treatments did not increase height, stem diameter, top dry mass, or root length. For Washington hawthorn, soil treatments did not increase height, stem diameter, or root length, but top dry mass in all treatments as a group and in humate-treated trees in particular was greater than that of controls. Roots of peat-treated trees of both species were longer than those in other treatments. Granular humate applied at 200 g/tree increased total root length more than did 100 g/tree in Washington hawthorn but not in red maple. Fertilizing at planting with N at 14.5 g·m-2 had no effect on any parameter measured for either species.

Relationships Among Potassium, Calcium and Trace Elements in Tree Leaves and Associated Canopy Arthropods

1990 ◽  
Vol 25 (3) ◽  
pp. 439-449 ◽  
Author(s):  
Lance S. Risley
Keyword(s):  
Tree Species ◽  
Acer Rubrum ◽  
Nutritional Ecology ◽  
Nutrient Cycles ◽  
Red Maple ◽  
Yellow Poplar ◽  
Flowering Dogwood ◽  
Quercus Prinus ◽  
The Relationship

There is a paucity of information that describes the relationship between the suite of nutrient elements in tree foliage and associated arthropod assemblages. Foliage from chestnut oak (Quercus prinus), hickories (Carya spp.), yellow poplar (Liriodendron tulipifera), red maple (Acer rubrum), and flowering dogwood (Cornus florida) and associated canopy arthropods were collected in an undisturbed and a 15 yr-old successional forested watershed and analyzed for K, Ca, Mn, Fe, Cu, Zn, Rb, and Sr. Foliar Mn and Sr were found in higher concentrations in the undisturbed watershed. Foliage from hickories was generally higher in concentrations of metals (Mn, Fe, Cu, Zn) compared with other tree species. Dogwood foliage had significantly higher concentrations of Ca and significantly lower concentrations of Mn than other tree species (P < 0.05). Concentrations of foliar elements in herbivore-damaged and undamaged leaves did not differ significantly (P > 0.05). Concentrations of elements in and among arthropod feeding categories varied substantially such that no trends were apparent among tree species and between watersheds. The most apparent trend among arthropod feeding categories was the relatively large accumulation of K in chewing herbivores (primarily caterpillars). In general, there appeared to be increases in K, Fe, Cu, and Zn concentrations from primary producers to consumers. This study contributes to arthropod nutritional ecology and to defining the role of canopy arthropods in forest ecosystem nutrient cycles.

Effect of gap harvesting on epiphytes and bark-dwelling arthropods in the Acadian forest of central Maine

2007 ◽  
Vol 37 (11) ◽  
pp. 2175-2187 ◽  
Author(s):  
Kathryn M. Miller ◽  
Robert G. Wagner ◽  
Stephen A. Woods
Keyword(s):  
Canonical Correlation ◽  
Acer Rubrum ◽  
Positive Association ◽  
Stem Bark ◽  
Red Maple ◽  
Arthropod Communities ◽  
Undisturbed Forest ◽  
Bark Texture ◽  
The Relationship

Using a long-term silvicultural experiment, we (i) investigated how epiphyte and arthropod communities were affected by height on the stem, bark texture, and stem diameter of red maple ( Acer rubrum L.) trees, (ii) examined how harvest gaps influenced epiphyte and arthropod communities on red maple boles, and (iii) explored whether these effects influenced the relationship between the epiphyte and arthropod communities. Arthropod and epiphyte assemblages dwelling on the bark of red maple trees located in undisturbed forest and harvest gaps varied with height. Bryophytes, Cladonia spp., and cyanolichens were most abundant near the base of the tree, while noncyano, foliose lichens and fruticose lichens were most abundant 4–6 m above the ground. Acari, Araneae, and Collembola were most abundant near the base of the tree, while Diptera were most abundant above 2 m. A previously undocumented assemblage of dipterans (flies), primarily in the suborder Nematocera, was found. Gap harvesting reduced the abundance of bryophytes, Collembola (springtails), Araneae (spiders), and total arthropods on the bark of red maple. Canonical correlation analysis revealed a positive association between bryophytes, Collembola, and Araneae. A strong correlation between Collembola and Araneae suggested a possible trophic interaction that may be affected by gap harvesting through a reduction in bryophyte abundance.

scholarly journals A Relationship Between Sulphur Content of Wool and Wool Production by Merino Sheep

1967 ◽  
Vol 20 (1) ◽  
pp. 153 ◽  
Author(s):  
PJ Reis ◽  
DA Tunks ◽  
OB Williams ◽  
AJ Williams
Keyword(s):  
Body Weight ◽  
Unit Area ◽  
Sulphur Content ◽  
Merino Sheep ◽  
Wool Production ◽  
Weight Index ◽  
Wool Growth ◽  
The Mean ◽  
Fleece Weight ◽  
The Relationship

The sulphur content of wool from 66 Peppin Merino wethers maintained together at pasture was measured in midside staples representing 49 weeks growth. The distribution of sulphur values was normal with a mean of 3�43 % and a range of 3�08-3�92 %. The sulphur content of the wool was inversely related to wool production among these sheep. There were no significant differences in the relationship when wool production was expressed as fleece weight index (F.W.I.), i.e. clean fleece weight/body weight (r = -0�48), as clean fleece weight (r = -0�42), or as wool growth per unit area of skin (r = - 0�37). The mean sulphur content of wool from sheep with the 10 highest values for F.W.I. was 3�27%, compared with a mean of 3 �55% sulphur for wool from sheep with the 10 lowest values for F.W.I.

Sign in / Sign up

Export Citation Format

Share Document