Competition dynamics in pure- versus mixed-family stands of loblolly and slash pine in the southeastern United States

Few studies within the native range of loblolly ( Pinus taeda L.) and slash pine ( Pinus elliottii Engelm. var. elliottii) have compared yield and stand dynamics in pure-family block versus mixed-family block plantings under a range of silvicultural treatments. Understanding intergenotypic competitive interactions is important for predicting phenotypic performance, defining growth strategies and ideotypes, and deploying the correct mix of families that possess complementary characteristics for enhanced yield and pest resistance. In 2000, replicated experimental trials were installed in the southeastern United States, controlling for genotype (pure- and mixed-family plantings; consisting of seven full-sibling loblolly and six full-sibling slash pine families), planting density (1334 vs. 2990 trees/ha), and levels of silvicultural treatment intensity (operational vs. intensive). We measured four installations of these trials. There were numerous examples of differential family performance in mixed versus pure plots manifested as significant deployment × family interactions for diameter at breast height, height, basal area, volume, survival, disease, and damage traits. Significant and consistent interactions of several families with mixed versus pure deployment led to the identification of putative crop and competition ideotypes in both loblolly and slash pine. Tree-level crown architectural traits and an index of growth efficiency for the identified families were consistent with the hypothesized ideotypes.

Download Full-text

Preemergence Weed Control in Southeastern Forest Nurseries

Weed Science ◽

10.1017/s004317450002720x ◽

1973 ◽

Vol 21 (4) ◽

pp. 363-366 ◽

Cited By ~ 1

Author(s):

T. R. Dill ◽

M. C. Carter

Keyword(s):

United States ◽

Pinus Taeda ◽

Weed Control ◽

Loblolly Pine ◽

Southeastern United States ◽

Pinus Elliottii ◽

Slash Pine ◽

High Rate ◽

Forest Nurseries ◽

Low Rate

Weed control trials were conducted on loblolly pine (Pinus taedaL.) or slash pine (Pinus elliottiiEngelm.) seedbeds at 12 locations in the southeastern United States. Good weed control was obtained from 2,4-bis-(isopropylamino)-6-(methylthio)-s-triazine (prometryne) at 2.2 and 4.5 kg/ha;N,N-dimethyl-2,2-diphenylacetamide (diphenamid) at 4.5 and 9 kg/ha; α,α,α-trifluoro-2,6-dinitro-N,N-dipropyl-p-toluidine (trifluralin) at 1.1 and 2.2 kg/ha; and 2-ethylthio-4,6-bis-isopropylamino-s-triazine (GS-16068) at 2.2 and 4.5 kg/ha as preemergence applications immediately followed by irrigation. Diphenamid and trifluralin treatments were not injurious to either pine species at either rate. GS-16068 was only slightly injurious at the high rate at one location. Prometryne was injurious at two locations at the high rate and at one location at the low rate.

Download Full-text

Estimated realized gains for first-generation slash pine (Pinus elliottii var. elliottii) tree improvement in the southeastern United States

Canadian Journal of Forest Research ◽

10.1139/x04-136 ◽

2004 ◽

Vol 34 (12) ◽

pp. 2587-2600 ◽

Cited By ~ 25

Author(s):

Rodrigo Vergara ◽

Timothy L White ◽

Dudley A Huber ◽

Barry D Shiver ◽

Donald L Rockwood

Keyword(s):

United States ◽

Rust Resistance ◽

First Generation ◽

Southeastern United States ◽

Volume Growth ◽

Pinus Elliottii ◽

Slash Pine ◽

Individual Tree ◽

The University ◽

Stand Yield

Realized gains from selection of the first-generation breeding population of slash pine (Pinus elliottii Engelm. var. elliottii) were estimated using data from 38 field trials planted in large rectangular plots in the southeastern United States. The trials consisted of material selected for volume growth and planted by the Cooperative Forest Genetics Research Program at the University of Florida (19 trials) and by the Plantation Management Research Cooperative at the University of Georgia (19 trials). All trials contained slash pine seedlots collected from unrogued or lightly rogued first-generation seed orchards. Analyses of variance detected, on average, moderate gains in rust resistance (I50 = 43.1%) and site index (4.3%) and important gains in individual tree volume (7.7%) and stand yield (10.2%). Silvicultural treatments and age by realized gains interactions were never significant, but significant interactions between seedlots and trials showed that realized gains are not consistent at all sites. Overall results were highly consistent with predicted breeding values for rust resistance, but lower than expected for volume. On average, realized gain in stand yield for first-generation material was approximately 10%, or an extra inside-bark volume of 25 m3·ha1 (357 feet3·acre1) at 25 years.

Download Full-text

Avian Breeding Season Diversity and Community Composition in Camden White Gum and Slash Pine Plantations

Forest Science ◽

10.1093/forsci/fxaa050 ◽

2021 ◽

Author(s):

Elizabeth J Messick ◽

Christopher E Comer ◽

Michael A Blazier ◽

T Bently Wigley

Keyword(s):

United States ◽

Species Richness ◽

Community Composition ◽

Pinus Elliottii ◽

The United States ◽

Slash Pine ◽

Planted Forests ◽

Eucalyptus Plantation ◽

Short Rotation Woody Crops ◽

Eucalyptus Plantations

Abstract In the southern United States, some landowners have established plantations of eucalyptus (Eucalyptus spp.) and are managing them on short rotations (<15 years) to provide wood for fiber and other potential uses. Establishment of short-rotation woody crops dominated by nonnative species has implications for resident fauna in the United States that are largely unknown. We compared avifauna abundance, diversity, and community composition in newly established Camden white gum (Eucalyptus benthamii) plantations with slash pine (Pinus elliottii) plantations of the same age and height (one to two and six to seven years old, respectively) in southwestern Louisiana, USA. Species richness, diversity, and community composition in newly established eucalyptus plantations and six- to seven-year-old pines were similar. More birds were observed, and bird detections varied less in eucalyptus plantations. Indigo buntings (Passerina cyanea) and other shrub-associated species were detected more often in eucalyptus stands. In contrast, species that inhabit herbaceous-dominated communities, such as eastern meadowlarks (Sturnella magna), or that were associated with a dense graminoid community (e.g., Bachman’s sparrow [Peucaea aestivalis]) were detected less often in eucalyptus. Overall, breeding bird communities in eucalyptus plantations one to two years postestablishment differed little from plantations dominated by slash pine. Study Implications Compared with slash pine (Pinus elliottii Englem) plantations of similar age and height (one to two years and six to seven years old, respectively) we found one- to two-year-old eucalyptus (Eucalyptus benthamii Maiden & Cambage) plantations supported similar avian species richness and diversity to six- to seven-year-old pine stands. Furthermore, we found these eucalyptus plantations (E13) supported an avian community that was intermediate to similar aged pine (S13) and pine of similar height (S08). However, avian communities will likely change as eucalyptus plantations age (Christian et al. 1997). Continued monitoring and assessment of community composition, richness, and abundance is important for determining the magnitude of this change. Future investigations focused on nest success, fecundity, postfledging monitoring, and survivorship compared with other types of planted forests and native cover types would help us better understand eucalyptus plantation effects on avifauna demographics (Van Horne 1983, Martin 1998, Jones 2001, Wood et al. 2004, Sage et al. 2006, Riffell et al. 2011).

Download Full-text

Variation among slash pine families in chlorophyll fluorescence traits

Canadian Journal of Forest Research ◽

10.1139/x03-035 ◽

2003 ◽

Vol 33 (6) ◽

pp. 1102-1109 ◽

Cited By ~ 10

Author(s):

Anita C Koehn ◽

James H Roberds ◽

Robert L Doudrick

Keyword(s):

Photosystem Ii ◽

Growth Traits ◽

Pinus Elliottii ◽

Nonphotochemical Quenching ◽

Slash Pine ◽

Photochemical Quenching ◽

Full Sibling ◽

Pretreatment Effects ◽

Pattern Of Variation ◽

Variance Profile

Photochemical quenching, nonphotochemical quenching, and yield of photosystem II were measured on seedlings of full-sibling, open-, and self-pollinated slash pine (Pinus elliottii Engelm. var. elliottii) families. Our results reveal that genetic variation in photochemical quenching and yield of photosystem II exists within this species. The pattern of variation found in these traits is consistent with the variance profile expected to occur as a result of segregation among nuclear genes. Variation among families accounted for 17% of the total variation observed in photochemical quenching, whereas the component for trees within families made up slightly more than 25% of the total. Less variation, both among families as well as among trees within families, was found for yield of photosystem II. A strikingly different pattern was observed for nonphotochemical quenching. Other than the error term, only pretreatment effects contributed significantly to the variation observed. This suggests that nonphotochemical quenching is largely influenced by environmental factors. With regard to associations between fluorescence and growth traits, both height and diameter growth were found to be positively correlated with photochemical quenching (0.36 and 0.33, respectively) when selfed and open-pollinated families were analyzed along with control-pollinated families.

Download Full-text

Understory Vegetation Richness and Diversity of Eucalyptus benthamii and Pinus elliottii Plantations in the Midsouth US

Forest Science ◽

10.1093/forsci/fxz051 ◽

2019 ◽

Author(s):

Andrea De Stefano ◽

Michael A Blazier ◽

Christopher E Comer ◽

Thomas J Dean ◽

T Bently Wigley

Keyword(s):

United States ◽

Species Richness ◽

Soil Ph ◽

Pinus Elliottii ◽

The United States ◽

Slash Pine ◽

Understory Vegetation ◽

Understory Species ◽

Species Richness And Diversity ◽

The Impact

Abstract In the Western Gulf region of the United States cold-tolerant eucalyptus have been explored as pulpwood feedstock. However, non-native plantations may alter understory species diversity, modifying environmental conditions and soil characteristics. Few studies have compared eucalyptus plantations with native ecosystems to understand the impact on understory vegetation in the United States. In this study, we compared understory plant species richness and diversity during 2014–2016 in (1) slash pine (Pinus elliottii) established in 2008, (2) slash pine established in 2013, and (3) and Camden white gum (Eucalyptus benthamii) established in 2013. Overstory characteristics, soil pH, and soil nutrient concentrations were measured to understand factors that affected understory species richness and diversity. Results indicated a decline in understory species richness over time, with Camden white gum in an intermediate condition between same-age slash pine (highest richness) and older slash pine (lowest richness). Leaf area index, soil pH and K, and tree height were the most important factors influencing understory species richness and diversity. The adoption of fast-growing eucalyptus on these sites will probably accelerate the deterioration of natural habitats and reduce open-condition species in favor of shade-tolerant species, overturning the conservation efforts already put in place by governmental agencies and conservation groups.

Download Full-text

Association of Recent Incidence of Foliar Disease in Pine Species in the Southeastern United States with Tree and Climate Variables

Forests ◽

10.3390/f11111155 ◽

2020 ◽

Vol 11 (11) ◽

pp. 1155

Author(s):

Karun Pandit ◽

Jason Smith ◽

Tania Quesada ◽

Caterina Villari ◽

Daniel J. Johnson

Keyword(s):

United States ◽

Pinus Palustris ◽

Pinus Elliottii ◽

Dew Point ◽

Climatic Variables ◽

Pine Forests ◽

Tree Level ◽

Hazard Mapping ◽

Foliar Disease ◽

Southern Pines

Pine forests in the southern United States are a major contributor to the global economy. Through the last three decades, however, there have been concerns about the decline of pine forests attributed mostly to pests and pathogens. A combination of biotic agents and environmental factors and their interaction often influences outbreaks and the resultant damage in the forests. Southern pines experience periodic mortality from bark beetles and root rot fungi and losses from fusiform rust and pitch canker have long been important for management. In recent years, there is also growing evidence of increasing damage from foliar disease in southern pines. Early detection of diseases following changes in foliar characteristics and assessment of potential risks will help us better utilize our resources and manage these forests sustainably. In this study, we used Forest Inventory and Analysis (FIA) data to explore the intensity of foliar disease in three common pines: loblolly (Pinus taeda L.), longleaf (Pinus palustris Mill.), and slash (Pinus elliottii Engelm.) in spatial and temporal terms using tree-level and climatic variables. Results from a tree-level model suggests that crown ratio may be an important factor in pine foliar disease (p < 0.1). We applied the MaxEnt model, a presence-only species distribution model (SDM), to explore any association of foliar disease incidences with the climatic variables at a landscape level. Results indicate that mean dew point temperature, maximum vapor pressure deficit, and precipitation during cold months had more influence over disease incidences than other climatic variables. While the sample size is limited as this is an emerging disease in the region, our study provides a basis for further exploration of disease detection methods, disease etiology studies, and hazard mapping.

Download Full-text

Economics of Ethanol Production Using Feedstock from Slash Pine (Pinus elliottii) Plantations in the Southern United States

Southern Journal of Applied Forestry ◽

10.1093/sjaf/35.2.61 ◽

2011 ◽

Vol 35 (2) ◽

pp. 61-66 ◽

Cited By ~ 10

Author(s):

Tyler S. Nesbit ◽

Janaki R.R. Alavalapati ◽

Puneet Dwivedi ◽

Marian V. Marinescu

Keyword(s):

United States ◽

Ethanol Production ◽

Cost Benefit Analysis ◽

Unit Cost ◽

Pinus Elliottii ◽

Slash Pine ◽

Biofuel Production ◽

Southern United States ◽

Land Values ◽

Ethanol Conversion

Abstract A growing interest in cellulosic biofuels, coupled with the economic challenges faced by nonindustrial private forestland (NIPF) owners of the Southern United States, presents a unique opportunity to useforest biomass as a feedstock for developing bioenergy markets. This study uses a cost-benefit analysis framework to calculate the profitability for three simulated NIPF slash pine (Pinus elliottii) plantations under multiple feedstock production levels. Also, the unit cost of cellulosic ethanol production considering both the two-stage dilute sulfuric acid (2SDSA) and proposed synthesis gas ethanol catalytic conversion (SGECC) processes is calculated through a discounted cash flow methodology. The results show that the bioenergy market opportunity increases land values by $28.56–37.50/ac. The calculated unit cost of production is found to be $2.39/gallon under the 2SDSA process and $1.16/gallon for the SGECC process. The overall analysis indicates that ethanol production from Southern slash pine plantations offers a promising option for biofuel production, but that further advancements are necessary in the ethanol conversion phase.

Download Full-text

The Impact of Weeding Regime, Planting Density, and Growth Habits on Watermelon Yield in an Organic System

HortTechnology ◽

10.21273/horttech04311-19 ◽

2019 ◽

Vol 29 (5) ◽

pp. 571-577

Author(s):

Suzanne P. Stone ◽

George E. Boyhan ◽

W. Carroll Johnson

Keyword(s):

United States ◽

Weed Control ◽

Growth Habit ◽

Southeastern United States ◽

Weed Suppression ◽

Planting Density ◽

Separate Experiment ◽

Organic System ◽

Growth Habits ◽

The Impact

The southeastern United States produces 50% of U.S. conventional watermelon (Citrullus lanatus) but only 7% of U.S. organic watermelon. Weeds are a major threat to watermelon yield in the southeastern United States, and organic weed control is estimated to cost 20-times more than conventional herbicide programs. The objectives of this study were to determine the optimal weed control regime to reduce hand-weeding costs while maintaining yield and to compare the weed suppression of two watermelon types with differing growth habits in an organic system. In 2014 and 2015, watermelon plots were randomly assigned to the following treatments in a factorial arrangement: vine or compact growth habit; 1.0- or 0.5-m in-row spacing; and weekly weed control (kept weed-free by hoeing and hand-pulling weeds) for 0, 4, or 8 weeks after transplanting (WAT). At the time of the watermelon harvest, not weeding resulted in average total weed densities of 86.6 and 87.0 weeds/m2, and weeding for 4 WAT resulted in average total weed densities of 26.4 and 7.0 weeds/m2 in 2014 and 2015, respectively. Nonetheless, weeding for 4 WAT resulted in watermelon yields and fruit counts comparable to those of weeding for 8 WAT during both years. This partial-season weeding regime resulted in 67% and 63% weeding cost reductions for vine and compact plants, respectively, in 2014, and a 43% reduction for both growth habit types in 2015. In 2015, a separate experiment that evaluated weeding regimes that lasted 0, 1, 2, 3, 4, and 8 WAT found that yields resulting from weeding for 3 WAT were greater than those resulting from weeding for 2 WAT. However, the yields did not differ when weeding was performed for 4 WAT and 8 WAT.

Download Full-text

Loblolly pine outperforms slash pine in the southeastern United States – A long-term experimental comparison study

Forest Ecology and Management ◽

10.1016/j.foreco.2019.117532 ◽

2019 ◽

Vol 450 ◽

pp. 117532 ◽

Cited By ~ 5

Author(s):

Dehai Zhao ◽

Bronson P. Bullock ◽

Cristian R. Montes ◽

Mingliang Wang ◽

Dale Greene ◽

...

Keyword(s):

United States ◽

Loblolly Pine ◽

Southeastern United States ◽

Slash Pine ◽

Experimental Comparison ◽

Comparison Study

Download Full-text

Financial Returns for Biomass on Short-Rotation Loblolly Pine Plantations in the Southeastern United States

Forest Science ◽

10.1093/forsci/fxab033 ◽

2021 ◽

Author(s):

Andrew Trlica ◽

Rachel L Cook ◽

Timothy J Albaugh ◽

Rajan Parajuli ◽

David R Carter ◽

...

Keyword(s):

United States ◽

Loblolly Pine ◽

Southeastern United States ◽

Field Studies ◽

Pine Plantations ◽

Planting Density ◽

Financial Returns ◽

Short Rotation ◽

Competition Control ◽

Whole Tree

Abstract Rising demand for renewable energy has created a potential market for biomass from short-rotation pine plantations in the southeastern United States. Site preparation, competition control, fertilization, and enhanced seedling genotypes offer the landowner several variables for managing productivity, but their combined effects on financial returns are unclear. This study estimated returns from a hypothetical 10-year biomass harvest in loblolly pine plantation using field studies in the Coastal Plain of North Carolina and the Virginia Piedmont testing combinations of tree genotype, planting density, and silviculture. Although enhanced varietal genotypes could yield more biomass, open-pollinated seedlings at 1,236–1,853 trees ha−1 under operational silviculture had the greatest returns at both sites, with mean whole-tree internal rates of return of 8.3%–9.9% assuming stumpage equal to current pulpwood prices. At a 5% discount rate, break-even whole-tree stumpage at the two sites in the optimal treatments was $8.72–$9.92 Mg−1, and break-even yield was 175–177 Mg ha−1 (roughly 18 Mg ha−1 yr−1 productivity), although stumpage and yield floors were higher if only stem biomass was treated as salable. Dedicated short-rotation loblolly biomass plantations in the region are more likely to be financially attractive when site establishment and maintenance costs are minimized. Study Implications: Our study suggests that dedicated loblolly pine plantations in the US Southeast may be managed to generate positive financial yields for biomass over relatively short (10 year) rotation windows, even at lower stumpage value than at present for pulpwood in the region (<80% current). Intensive use of costly inputs like fertilizer, vigorous chemical competition control, and elite genetics in planting stock did improve biomass yields. However, the management combinations that favored the highest financial returns emphasized the least expensive open-pollinated stock, lower-input operational silviculture, and moderate-to-high planting density.

Download Full-text