Dispersal and viability of seeds from cones in tops of harvested loblolly pines

2001 ◽  
Vol 31 (2) ◽  
pp. 357-362 ◽  
Author(s):  
Michael G Shelton ◽  
Michael D Cain
Keyword(s):  
Seed Maturation ◽  
Potential Contribution ◽  
Seed Supply ◽  
Seed Cone ◽  
Standing Trees ◽  
Loblolly Pines ◽  
Closed Canopy ◽  
Viable Seeds ◽  
Pinus Taeda L ◽  
Dispersal Period

Seed supply is one of the most important determinants of successful natural regeneration. We conducted a study to determine the potential contribution of cones in the tops of harvested loblolly pines (Pinus taeda L.) to the stand's seed supply if trees were felled after seed maturation but before dispersal. Closed cones, collected in October 1996, were stored in wire cages with periodic removals over 2 years to determine the number and viability of extracted seeds. Storage sites were an opening in a seed-tree stand and a closed-canopy pine-hardwood stand in southeastern Arkansas. Of the initial 83 viable seeds/cone, 73% had dispersed in the opening and 63% in the closed stand by March 1997, which is considered the end of the normal dispersal period from standing trees. By October 1997, only 1 viable seed/cone remained in the opening and 5 viable seeds/cone in the closed stand, indicating rather complete dispersal or mortality of seeds by the first summer after harvest. Results indicate that cones in tops of trees cut during the 2-month period after seed maturation and before substantial dispersal can make an important contribution to the stand's seed supply, especially in reproduction cutting methods where most of the trees are harvested.

scholarly journals Effect of desiccation temperature on viability of immature dandelion (Taraxacum agg.) seeds dried in mowed inflorescences

2010 ◽  
Vol 56 (No. 12) ◽  
pp. 580-583 ◽  
Author(s):  
Z. Martinková ◽  
A. Honěk
Keyword(s):  
Seed Dispersal ◽  
High Temperatures ◽  
Seed Viability ◽  
Late Summer ◽  
Seed Maturation ◽  
Ripe Seed ◽  
Viable Seeds

After flowering has ceased, dandelion (Taraxacum agg.) capitula close to enable maturation of seeds. In late summer the period of seed maturation lasts for 9 days. The capitula mowed later than 4 days after the start of this period and desiccated at 25°C produce viable seeds. If cut and prostrated on insolated ground inflorescences can experience temperatures exceeding 50°C which may impair seed viability. We determined the effect of desiccation temperature (5, 15, 25, 35, 45 or 55°C) on viability of ripening seeds using inflorescences harvested on September 5, 2008 at Prague-Ruzyne (50°05'N, 14°18'09 E), five days after flowering ceased (about 4 days before seed dispersal). As control, ripe seeds were collected at dispersal on the same day and desiccated at identical temperatures. Desiccated seeds were germinated at constant 17°C. Ripening seeds of maturing capitula only remained germinable if desiccation temperatures were ≤ 35°C (optimum 25°C) and were killed at 45 and 55°C. The viability of ripe seed was not affected by any of the desiccation temperatures. Time of germination of 50% seeds that germinated was significantly shorter in ripe than ripening seeds. Exposure of mowed dandelion inflorescences on insolated ground (solarization) may thus decrease production of viable seeds because of high temperatures experienced during desiccation.  

Tolerance of Loblolly Pines to Fusiform Rust

1995 ◽  
Vol 19 (2) ◽  
pp. 60-64 ◽  
Author(s):  
Charles H. Walkinshaw ◽  
James P. Barnett
Keyword(s):  
Pinus Taeda ◽  
Rust Fungus ◽  
The Other ◽  
Diameter Growth ◽  
Mature Trees ◽  
Fusiform Rust ◽  
Infected Tree ◽  
Loblolly Pines ◽  
Pinus Taeda L ◽  
Natchez Trace Parkway

Abstract Loblolly pines (Pinus taeda L.) that were 8 to 17 yr old tolerated one to three fusiform rust (Cronartium quercuum [Berk.] Miyabe ex Shiraif sp. fusiforme) galls in their stems. Families with four or more galls in their stems lost 25% or more of the trees by age 17. In living trees with less than four stem galls, diameter growth was comparable to that of trees with no galls. Tolerance was indicated by the ability of loblolly pines to maintain the rust fungus in stems that had dbh's similarto asymptomatic trees on the same site. In plantations, the number of galls in the stem was generally one to two per infected tree. This was also true for mature trees (12 to 38 in. dbh) along the Natchez Trace Parkway. These trees have been infected with fusiform rust for nearly 100 yr. On the other hand, the presence of four or more stem galls seems to be a reliable indicator of mortality rather than tolerance. South. J. Applied For. 19 (2): 60-64.

Response of Newly Planted Loblolly Pines to Herbicide and Nitrogen

1988 ◽  
Vol 12 (1) ◽  
pp. 33-36 ◽  
Author(s):  
William H. McKee ◽  
Larry P. Wilhite
Keyword(s):  
Pinus Taeda ◽  
Loblolly Pine ◽  
Coastal Plain ◽  
Fold Increase ◽  
Atlantic Coastal Plain ◽  
Pronounced Increase ◽  
Seedling Biomass ◽  
Loblolly Pines ◽  
Pinus Taeda L ◽  
Atlantic Coastal

Abstract In three separate studies on the Lower Atlantic Coastal Plain, sites were sheared, root-raked, and bedded, and phosphorus was applied. Loblolly pine (Pinus taeda L.) seedlings were planted, and nitrogen fertilizer and preemergence herbicide were applied at several different times. In all three studies, loblolly pine responded positively in height, diameter, and aboveground biomass to herbicide applied in the spring following planting. Responses to nitrogen application were inconsistent. A pronounced increase in growth was found in only one study. There, a nitrogen and a herbicide treatment interacted to give a three-fold increase in aboveground seedling biomass after one growing season. The lack of response to nitrogen in the other two studies may be attributable to low rainfall in the spring after planting and mineralization of native nitrogen from soil organic matter. South. J. Appl. For. 12(1):33-36.

Fractal analysis of foliage distribution in loblolly pine crowns

1998 ◽  
Vol 28 (1) ◽  
pp. 106-114 ◽  
Author(s):  
Boris Zeide
Keyword(s):  
Fractal Dimension ◽  
Pinus Taeda ◽  
Loblolly Pine ◽  
Spatial Factors ◽  
Diameter Increment ◽  
Single Crown ◽  
Loblolly Pines ◽  
Fractal Characteristics ◽  
Foliage Density ◽  
Pinus Taeda L

A new method for estimating fractal characteristics (fractal dimension and foliage density) of a single crown or its portions is developed. The proposed method operates with volume and mass of natural units of the crown, such as shoots and branches, rather than with numbers of regular cubes. Fractal dimension alone is not sufficient to describe foliage distribution in the crown because it says nothing about the density of foliage at a given point. The density is defined as the ratio of foliage mass to fractal volume it occupies. Fortunately, the intercept of the regression, which contains fractal dimension as the slope, provides a measure of foliage density. Thus the method makes it possible to separate purely spatial factors represented by fractal dimension from ecophysiological effects characterized by foliage density. Application of the method showed that neither fractal dimension nor foliage density of the studied loblolly pines (Pinus taeda L.) correlates with current diameter increment. At the same time, there is a pronounced negative correlation between fractal dimension and crown size. These results suggest that as crowns become larger, the amount of foliage located at the crown periphery increases in proportion to the foliage amount inside the crown. As a spin-off of this analysis, a method for estimating relative foliage density (defined as the ratio of actual to maximal foliage mass for a given branch) is developed.

Total biomass and nutrients of 25-year-old loblolly pines (Pinus taeda L.)

1984 ◽  
Vol 9 (3) ◽  
pp. 155-160 ◽  
Author(s):  
Charles E. Pehl ◽  
Charles L. Tuttle ◽  
James N. Houser ◽  
David M. Moehring
Keyword(s):  
Pinus Taeda ◽  
Total Biomass ◽  
Loblolly Pines ◽  
Pinus Taeda L

Compatible Tree-volume and Upper-Stem Diameter Equations for Plantation Loblolly Pines in the West Gulf Region

1991 ◽  
Vol 15 (2) ◽  
pp. 92-97 ◽  
Author(s):  
V. C. Baldwin ◽  
D. P. Feduccia
Keyword(s):  
Loblolly Pine ◽  
Stem Diameter ◽  
Simultaneous Estimation ◽  
Parameter Estimates ◽  
Model Formulation ◽  
Gulf Region ◽  
The West ◽  
Loblolly Pines ◽  
Gulf States ◽  
Pinus Taeda L

Abstract Equations are presented for predicting inside bark (ib) or outside bark (ob) cubic-foot volume to any ob diameter limit, or the ib or ob diameter at any given height, of loblolly pine tress (Pinus taeda L.) growing in thinned or unthinned plantations in the West Gulf States region. The model formulation and simultaneous estimation technique utilized ensure that the volume and stem profile equations are compatible and the parameter estimates are statistically efficient. The 230 sample trees used to develop the equations were from central Louisiana plantations and ranged in diameters at breast height (D) from 1.3 to 20.8 in. in total height (H) from 16 to 96 ft, and in ages from 9 to 55 yr. Significant differences in stem profile between trees of the same D and H in unthinned and thinned plantations suggest that separate cubic-foot volume and upper-stem diameter prediction equations should be used South J. Appl. For. 15(2):92-97

Relationships between acoustic variables and different measures of stiffness in standing Pinus taeda trees

2009 ◽  
Vol 39 (8) ◽  
pp. 1421-1429 ◽  
Author(s):  
Christian R. Mora ◽  
Laurence R. Schimleck ◽  
Fikret Isik ◽  
Jerry M. Mahon ◽  
Alexander Clark ◽  
...  
Keyword(s):  
Pinus Taeda ◽  
Dynamic Stiffness ◽  
Reference Method ◽  
Systematic Bias ◽  
Standing Tree ◽  
Static Stiffness ◽  
Standing Trees ◽  
Acoustic Velocities ◽  
Pinus Taeda L ◽  
Good Agreement

Acoustic tools are increasingly used to estimate standing-tree (dynamic) stiffness; however, such techniques overestimate static stiffness, the standard measurement for determining modulus of elasticity (MOE) of wood. This study aimed to identify correction methods for standing-tree estimates making dynamic and static stiffness comparable. Sixty Pinus taeda L. trees, ranging from 14 to 19 years old, obtained from genetic tests established in the southeastern United States, were analyzed. Standing-tree acoustic velocities were measured using the TreeSonic tool. Acoustic velocities were also recorded in butt logs cut from the same trees using the Director HM200. A strong but biased relationship between tree and log velocities was observed, with tree velocities 32% higher (on average) than the corresponding log velocities. Two correction methods, one for calibrating tree velocities and one for accounting for differences in wood moisture content, were used to determine an adjusted MOE. After correction, adjusted MOE estimates were in good agreement with static longitudinal MOE values measured on clearwood specimens obtained from the trees, and no systematic bias was observed. The results of this study show that acoustic estimates of MOE on standing trees largely depend on how the data are processed and the reference method used.

scholarly journals Effects of Early Release on Natural Versus Container Loblolly Pines 12 Years After Field Establishment

2002 ◽  
Vol 26 (4) ◽  
pp. 173-180 ◽  
Author(s):  
Michael D. Cain ◽  
James P. Barnett
Keyword(s):  
Pinus Taeda ◽  
Loblolly Pine ◽  
Early Release ◽  
Percentage Points ◽  
Competition Control ◽  
Genetically Improved ◽  
Loblolly Pines ◽  
Pinus Taeda L

Abstract Genetically improved, container loblolly pine (Pinus taeda L.) seedlings were compared to naturally established loblolly seedlings on a cutover pine site. Crop pines on 6 of 12 plots were released from woody and herbaceous competition within a 2 ft radius of each stem. On release plots, woody competition was controlled by hand-cutting for 5 consecutive yr and herbaceous competition was controlled with herbicides for 4 consecutive yr after pine establishment. Competition control increased 12 yr survival by 68 percentage points for natural pines and by 47 percentage points for planted pines. Twelve years after field establishment, mean-tree volume of planted pines was no different than that of naturally established pines. Nevertheless, volume gains of 150% to 200% were achieved within regeneration techniques as a result of release. South. J. Appl. For. 26(4):173–180.

Thinning Young Loblolly Pine Stands With Fire

1993 ◽  
Vol 3 (3) ◽  
pp. 169 ◽  
Author(s):  
DD Wade
Keyword(s):  
Ambient Temperature ◽  
Pinus Taeda ◽  
Loblolly Pine ◽  
Southeastern United States ◽  
Wide Range ◽  
Loblolly Pines ◽  
Pine Stands ◽  
Pinus Taeda L ◽  
The Relationship ◽  
Stem Girdling

The relationship between fire-caused stem girdling and groundline diameter (GLD) in loblolly pine (Pinus taeda L.) was determined. Results of 10 experimental prescribed bums conducted across a wide range of ambient temperature conditions during both the dormant and growing season demonstrate that low-intensity backing fires (< 346 KW/m) are an effective tool to eliminate loblolly pines less than 3.8 cm (1.5 in.) GLD. Wide differences in ambient temperature at time of burning did not affect stem kill of unscorched trees in this study. Virtually all fire-caused mortality took place within four months postburn. A predictive model that explained 92% of the variation in mortality was developed to facilitate the use of fire to thin young, overcrowded loblolly pine stands in the southeastern United States. Use of this model in conjunction with a preburn stand survey allows estimation of the number and distribution of survivors prior to ignition.

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