| resin acids; the composition of the gum oleoresin acids of pinus palustris. | | 1948 | 18102920 |
| forest floor depth mediates understory vigor in xeric pinus palustris ecosystems. | longleaf pine (pinus palustris) woodlands and savannas are among the most frequently burned ecosystems in the world with fire return intervals of 1-10 years. this fire regime has maintained high levels of biodiversity in terms of both species richness and endemism. land use changes have reduced the area of this ecosystem by >95%, and inadequate fire frequencies threaten many of the remnants today. in the absence of frequent fire, rapid colonization of hardwoods and shrubs occurs, and a broad-lea ... | 2007 | 17494398 |
| adjustments in hydraulic architecture of pinus palustris maintain similar stomatal conductance in xeric and mesic habitats. | we investigated relationships between whole-tree hydraulic architecture and stomatal conductance in pinus palustris mill. (longleaf pine) across habitats that differed in soil properties and habitat structure. trees occupying a xeric habitat (characterized by sandy, well-drained soils, higher nitrogen availability and lower overstory tree density) were shorter in stature and had lower sapwood-to-leaf area ratio (a(s):a(l)) than trees in a mesic habitat. the soil-leaf water potential gradient (ps ... | 2006 | 17080605 |
| effects of elevated atmospheric carbon dioxide on biomass and carbon accumulation in a model regenerating longleaf pine community. | plant species vary in response to atmospheric co2 concentration due to differences in physiology, morphology, phenology, and symbiotic relationships. these differences make it very difficult to predict how plant communities will respond to elevated co2. such information is critical to furthering our understanding of community and ecosystem responses to global climate change. to determine how a simple plant community might respond to elevated co2, a model regenerating longleaf pine community comp ... | 2006 | 16825468 |
| light quality treatments enhance somatic seedling production in three southern pine species. | embryogenic cultures of loblolly pine (pinus taeda l.), slash pine (pinus elliottii engelm.), longleaf pine (pinus palustris mill.) and slash pine x longleaf pine hybrids were initiated from immature seeds on an initiation medium containing 13.57 microm 2,4-dichlorophenoxyacetic acid and 2.22 microm benzylaminopurine. embryogenic cultures proliferated and somatic embryos developed, matured and germinated following a modified protocol and media originally developed for radiata pine (pinus radiata ... | 2006 | 16356915 |
| extracting dna from submerged pine wood. | a dna extraction protocol for submerged pine logs was developed with the following properties: (i) high molecular weight dna, (ii) pcr amplification of chloroplast and nuclear sequences, and (iii) high sequence homology to voucher pine specimens. the dna extraction protocol was modified from a cetyltrimehtylammonium bromide (ctab) protocol by adding stringent electrophoretic purification, proteinase k, rnase, polyvinyl pyrrolidone (pvp), and gene releaser. chloroplast rbcl (ribulose-1,5-bisphosp ... | 2004 | 15499414 |
| stomatal sensitivity to vapor pressure deficit and its relationship to hydraulic conductance in pinus palustris. | we studied the response of stomatal conductance at leaf (gs) and canopy (gs) scales to increasing vapor pressure deficit (d) in mature pinus palustris mill. (longleaf pine) growing in a sandhill habitat in the coastal plain of the southeastern usa. specifically, we determined if variation in the stomatal response to d was related to variation in hydraulic conductance along the soil-to-leaf pathway (kl) over the course of a growing season. reductions in kl were associated with a severe growing se ... | 2004 | 14996660 |
| species-specific patterns of hydraulic lift in co-occurring adult trees and grasses in a sandhill community. | plants can significantly affect ecosystem water balance by hydraulic redistribution (hr) from dry to wet soil layers via roots (also called hydraulic lift, hl, when the redistribution is from deep to shallow soil). however, the information on how co-occurring species in natural habitats differ in hl ability is insufficient. in a field study, we compared hl ability of four tree species (including three congeneric oak species) and two c4 bunch grass species that co-occur in subxeric habitats of fa ... | 2004 | 14689298 |
| on the number of genes controlling the grass stage in longleaf pine. | the grass stage is an inherent and distinctive developmental trait of longleaf pine (pinus palustris), in which height growth in the first few years after germination is suppressed. in operational forestry practice the grass stage extends for two to several years and often plays a role in planting failures and decisions to plant alternative species. interspecies hybrids involving loblolly (p. taeda) and slash (p. elliottii var. elliottii) pines have been investigated as a means to produce planti ... | 2003 | 14557392 |
| controls of fine root dynamics across a gradient of gap sizes in a pine woodland. | controls of fine dynamics were investigated in a pinus palustris mill. (longleaf pine) woodland subjected to two understory vegetation treatments (control versus removed) and four overstory treatments (no gap control, and canopy gaps of three sizes with constant total gap area per stand). fine root (<2 mm diameter) dynamics were measured over 11 months using ingrowth cores (all treatments) and minirhizotrons (understory removed in no gap control and large gap treatments only). at the fine (micro ... | 2003 | 12647190 |
| mapping quantitative trait loci controlling early growth in a (longleaf pine x slash pine) x slash pine bc(1) family. | random amplified polymorphic dna (rapd) markers were employed to map the genome and quantitative trait loci controlling the early growth of a pine hybrid f(1) tree ( pinus palustris mill. x p. elliottii engl.) and a recurrent slash pine tree ( p. elliottii engl.) in a (longleaf pine x slash pine) x slash pine bc(1) family consisting of 258 progeny. of the 150 hybrid f(1) parent-specific rapd markers, 133 were mapped into 17 linkage groups covering a genetic distance of 1,338.2 cm. of the 116 sla ... | 2002 | 12582646 |
| nitrogen decreases and precipitation increases ectomycorrhizal extramatrical mycelia production in a longleaf pine forest. | the rates and controls of ectomycorrhizal fungal production were assessed in a 22-year-old longleaf pine (pinus palustris mill.) plantation using a complete factorial design that included two foliar scorching (control and 95% plus needle scorch) and two nitrogen (n) fertilization (control and 5 g n m(-2) year(-1)) treatments during an annual assessment. ectomycorrhizal fungi production comprised of extramatrical mycelia, hartig nets and mantles on fine root tips, and sporocarps was estimated to ... | 2007 | 17260146 |
| tissue chemistry and carbon allocation in seedlings of pinus palustris subjected to elevated atmospheric co(2) and water stress. | longleaf pine (pinus palustris mill.) seedlings were grown in 45-l pots and exposed to ambient or elevated (365 or 730 &mgr;mol co(2) mol(-1)) co(2) concentration in open-top chambers for 20 months. two water-stress treatments (target values of -0.5 or -1.5 mpa xylem pressure potential) were imposed 19 weeks after initiation of the study. at harvest, tissues (needles, stems, taproots, coarse roots, and fine roots) were analyzed for carbon (c), nitrogen (n), nonpolar extractives (fats, waxes, and ... | 1999 | 12651576 |
| distribution of native legumes (leguminoseae) in frequently burned longleaf pine (pinaceae)-wiregrass (poaceae) ecosystems. | legume species distribution and abundance and selected environmental variables were quantified across a complex gradient (varying in both water-holding capacity and fertility) for frequently burned longleaf pine (pinus palustris)-wiregrass (aristida stricta) ecosystems. legumes were present in all months; however, abundance peaked in june and was minimal after killing frosts in october. legume species were prominent in the flora (43 species encountered) ubiquitous (94% of 2-m subplots had at lea ... | 1999 | 10562251 |
| optical properties of intact leaves for estimating chlorophyll concentration. | changes in leaf chlorophyll content can serve as relative indicators of plant vigor and environmental quality. this study identified reflectance, transmittance, and absorptance wavebands and band ratios within the 400- to 850-nm range for intact leaves that could be used to estimate extracted leaf chlorophyll per unit leaf area (areal concentration) with minimal error. leaf optical properties along with chlorophyll a, b, and a + b concentrations were measured for the planar-leaved sweetgum (liqu ... | 2002 | 12371158 |
| cavity excavation and enlargement as mechanisms for indirect interactions in an avian community. | direct and indirect species interactions within ecological communities may play a strong role in influencing or maintaining community structure. complex community interactions pose a major challenge to predicting ecosystem responses to environmental change because predictive frameworks require identification of mechanisms by which community interactions arise. cavity-nesting communities are well suited for mechanistic studies of species interactions because cavity nesters interact through the cr ... | 2008 | 18409439 |
| dependence of needle architecture and chemical composition on canopy light availability in three north american pinus species with contrasting needle length. | morphology and chemical composition of needles of shade-intolerant southern conifers (pinus palustris mill. (mean needle length +/- sd = 29.1 +/- 4.1 cm), p. taeda l. (12.3 +/- 2.9 cm) and p. virginiana mill. (5.1 +/- 0.8 cm)) were studied to test the hypothesis that foliage acclimation potential to canopy light gradients is generally low for shade-intolerant species, and in particular, because of mechanical limitations, in species with longer needles. plasticity for each needle variable was def ... | 2002 | 12184979 |
| root dynamics in an artificially constructed regenerating longleaf pine ecosystem are affected by atmospheric co(2) enrichment. | differential responses to elevated atmospheric co(2) concentration exhibited by different plant functional types may alter competition for above- and belowground resources in a higher co(2) world. because c allocation to roots is often favored over c allocation to shoots in plants grown with co(2) enrichment, belowground function of forest ecosystems may change significantly. we established an outdoor facility to examine the effects of elevated co(2) on root dynamics in artificially constructed ... | 2001 | 11378173 |
| developmental and light-regulated expression of individual members of the light-harvesting complex b gene family in pinus palustris. | angiosperms requires light for multiple aspects of chloroplast development, including chlorophyll synthesis and induction of expression of the mrnas encoding the major polypeptides of the light-harvesting complex of photosystem ii (lhcb genes). in contrast, many conifers, including pines, firs, and spruces, can accumulate chlorophyll and the light-harvesting chlorophyll a/b-binding proteins of photosystem ii in complete darkness. to understand the factors responsible for the regulation of expres ... | 1996 | 8787030 |
| hydraulic architecture and tracheid allometry in mature pinus palustris and pinus elliottii trees. | pinus palustris mill. (longleaf pine, ll) and pinus elliottii engelm. var. elliottii (slash pine, sl) frequently co-occur in lower coastal plain flatwoods of the usa, with ll typically inhabiting slightly higher and better-drained microsites than sl. the hydraulic architecture and tracheid dimensions of roots, trunk and branches of mature ll and sl trees were compared to understand their role in species microsite occupation. root xylem had higher sapwood-specific hydraulic conductivity (k(s)) an ... | 2010 | 20103778 |
| aedes albopictus (diptera: culicidae) oviposition response to organic infusions from common flora of suburban florida. | we evaluated the oviposition response of gravid aedes albopictus (skuse) to six organic infusions. laboratory and field-placed oviposition cups baited with water oak (quercus nigra l.), longleaf pine (pinus palustris p. mill), or st. augustine grass (stenotaphrum secundatum (walt.) kuntze), as well as binary infusion mixtures of each, were used. in addition, a triple-cage, dual port olfactometer was used to measure upwind response of gravid individuals to these infusions. we found that ae. albop ... | 2010 | 21175935 |
| measuring external mycelia production of ectomycorrhizal fungi in the field: the soil matrix matters. | assessing mycorrhizal fungi production in field settings has been hindered by the inability to measure external mycelia. recently, external mycelia production was measured in the field using a novel in-growth core technique with acid-washed sand as the in-growth matrix. here, we tested the assumption that external mycelia production in acid-washed sand is representative of that in native soil. external mycelia production was estimated as the difference in fungal growth between closed (allowing o ... | 2006 | 16771993 |
| small-scale fuel variation alters fire intensity and shrub abundance in a pine savanna. | small-scale variation in fire intensity and effects may be an important source of environmental heterogeneity in frequently burned plant communities. we hypothesized that variation in fire intensity resulting from local differences in fuel loads produces heterogeneity in pine savanna ground cover by altering shrub abundance. to test this hypothesis, we experimentally manipulated prefire fuel loads to mimic naturally occurring fuel-load heterogeneity associated with branch falls, needle fall near ... | 2006 | 16761611 |
| plants as bio-monitors for cs-137, pu-238, pu-239,240 and k-40 at the savannah river site. | the savannah river site was constructed in south carolina to produce plutonium (pu) in the 1950s. discharges associated with these now-ceased operations have contaminated large areas within the site, particularly streams associated with reactor cooling basins. evaluating the exposure risk of contamination to an ecosystem requires methodologies that can assess the bioavailability of contaminants. plants, as primary producers, represent an important mode of transfer of contaminants from soils and ... | 2011 | 21412545 |
| productivity and species richness across an environmental gradient in a fire-dependent ecosystem. | the fire-dependent longleaf pine-wiregrass (pinus palustris mill.-aristida beyrichiana trin. & rupr.) savannas of the southeastern united states provide a unique opportunity to examine the relationship between productivity and species richness in a natural ecosystem because of the extremely high number of species and their range across a wide ecological amplitude (sandhills to edges of wetlands). we used a natural gradient to examine how plant species richness and plant community structure vary ... | 2001 | 21669643 |
| influence of plant-parasitic nematodes on longleaf pine seedlings. | seedlings of longleaf pine (pinus palustris) were grown in 20-cm pots for 5 to 7 months in the greenhouse following inoculation with a high or low level of one of seven species of plant-parasitic nematodes. belonolaimus longicaudatus and helicotylenchus dihystera had no effect on seedling growth. high inoculum densities of hoplolaimus galeatus and tylenchorhynchus claytoni caused a significant reduction of fresh weight of seedling roots. root and top weights of seedlings grown in soil infested w ... | 1973 | 19319287 |
| tree species fine-root demography parallels habitat specialization across a sandhill soil resource gradient. | single species can substantially alter belowground processes in ecosystems via differential root production and death. however, information on species differences in fine-root demography is virtually absent for natural communities. in this field study, we recorded species-specific fine-root (<2 mm in diameter) demography in adults of four tree species (pinus palustris, quercus laevis, q. incana, and q. margaretta) that are distributed differentially along soil resource gradients in the fall-line ... | 2009 | 19694127 |
| hydraulic design of pine needles: one-dimensional optimization for single-vein leaves. | single-vein leaves have the simplest hydraulic design possible, yet even this linear water delivery system can be modulated to improve physiological performance. we determined the optimal distribution of transport capacity that minimizes pressure drop per given investment in xylem permeability along the needle for a given length without a change in total water delivery, or maximizes needle length for a given pressure difference between petiole and needle tip. this theory was tested by comparativ ... | 2006 | 17087464 |
| influence of atmospheric co2 enrichment, soil n, and water stress on needle surface wax formation in pinus palustris (pinaceae). | interactive effects of increasing atmospheric co2 with resource limitations on production of surface wax in plants have not been studied. pinus palustris seedlings were grown for 1 yr at two levels of soil n (40 or 400 kg n_ha-1_yr-1) and water stress (-0.5 or -1.5 mpa xylem pressure potential) in open-top field chambers under two levels of co2 (365 or 720 mumol/mol). needle surface wax content was determined at 8 mo (fall) and 12 mo (spring) and epicuticular wax morphology was examined using sc ... | 1997 | 21708662 |
| fine root branch orders respond differentially to carbon source-sink manipulations in a longleaf pine forest. | fine roots are a key component of carbon (c) flow and nitrogen (n) cycling in forest ecosystems. however, the complexity and heterogeneity of the fine root branching system have hampered the assessment and prediction of c and n dynamics at ecosystem scales. we examined how root morphology, biomass, and chemistry differed with root branch orders (1-5 with root tips classified as first order roots) and how different root orders responded to increased c sink strength (via n fertilization) and reduc ... | 2004 | 15179577 |
| phytochrome in embryos of pinus palustris. | | 1969 | 16657024 |
| suitability of some southern and western pines as hosts for the pine shoot beetle, tomicus piniperda (coleoptera: scolytidae). | the pine shoot beetle, tomicus piniperda (l.), is an exotic pest that has become established in north america. discovered in ohio in 1992, it has since been found in at least 13 states and parts of canada. the beetle can cause significant growth loss in pines, and it represents a potential threat to trees in areas where it has not yet become established. to evaluate this threat to native pines, field and laboratory tests were conducted on several common and important southern and western species ... | 2004 | 15154468 |
| effects of atmospheric co(2) on longleaf pine: productivity and allocation as influenced by nitrogen and water. | longleaf pine (pinus palustris mill.) seedlings were exposed to two concentrations of atmospheric co(2) (365 or 720 micro mol mol(-1)) in combination with two n treatments (40 or 400 kg n ha(-1) year(-1)) and two irrigation treatments (target values of -0.5 or -1.5 mpa xylem pressure potential) in open-top chambers from march 1993 through november 1994. irrigation treatments were imposed after seedling establishment (i.e., 19 weeks after planting). seedlings were harvested at 4, 8, 12, and 20 mo ... | 1997 | 14759848 |