01691nas a2200217   4500008004100000245009600041210006900137300001400206490000700220520098700227653001201214653003201226653001401258653001101272653002801283100002301311700003801334700002501372700003201397856004401429       2011                        eng d00aThe taxonomic status of the Mexican oak Quercus undata (Fagaceae, Quercus, section Quercus)0 ataxonomic status of the Mexican oak Quercus undata Fagaceae Quer  a1123-11310 v823 a<p>Quercus undata Trel. (Fagaceae, Quercus, Section Quercus) has a complex taxonomic and nomenclatural history. Intensive sampling of oaks at the type locality of Q. undata Trel. in Durango, Mexico and evaluation of herbarium specimens and plants in the field indicate that Q. undata represents variation in Quercus chihuahuensis Trel. in white oak communities where introgressive hybridization among Q. chihuahuensis, Q. grisea Liebm., and a third white oak, Q. arizonica Sarg. made species identification difficult. Endlich&rsquo;s type specimen of Q. undata, as designated by Trelease, was apparently destroyed in bombing raids on Berlin during World War II, and we propose herein as lectotype the Trelease illustration of the type. An epitype is also designated in support of the lectotype, given that some features cannot be critically observed on the illustration. The long peduncles of the specimen illustrated by Trelease indicate a close relation to Q. chihuahuensis.</p>
10aepitype10aintrogressive hybridization10alectotype10aMexico10aSierra Madre Occidental1 aBacon, Jeffrey, R.1 aDávila-Aranda, Patricia, Dolores1 aSpellenberg, Richard1 aGonzález-Elizondo, Socorro  uhttps://quercus.myspecies.info/node/17900809nas a2200109   4500008004100000245004100041210003700082490000700119520050400126100002600630856004300656       1961                        eng d00aThe Live Oaks of the Series Virentes0 aLive Oaks of the Series Virentes0 v653 aKey and descriptions of the 6 species and 1 variety are illustrated, distinctions being based upon morphological, geographic, and ecological (soil tolerance) data. New dispositions include Quercus minima Small X Q. chapmani Sarg. (r Q. rolfsii Small), Q. hemis- pherica var. maritima (= Q. phellos /3 maritima Michx. - not Q. vir- giniana var. maritima Sarg., a misidentification), Q. virginiana Mill. (= Q. oleoides var. quaterna C. H. Mull.), and Q. oleoides var. sagraeana (= Q. sagraeana Nutt.).1 aMuller, Cornelius, H.  uhttps://quercus.myspecies.info/node/9900470nas a2200121   4500008004100000245015100041210006900192260000900261300001200270490000600282100001700288856004300305       1977                        eng d00aNumerical analysis of the scarlet oak complex (Quercus subgen. Erythrobalanus) in the eastern United states: relationships above the species level0 aNumerical analysis of the scarlet oak complex Quercus subgen Ery  c1977  a122-1330 v21 aJensen, R.J.  uhttps://quercus.myspecies.info/node/9404339nas a2200493   4500008004100000245007900041210006900120260000900189300001200198490000700210520295400217653001603171653002303187653002003210653001803230653004103248653001203289653001903301653001303320653003703333653002803370653002103398653002003419653002003439653001803459653001603477653001303493653001203506653002903518653003003547653002103577653001803598653002603616653001903642653002003661653001703681653002403698653002003722653001303742100001603755700001603771700001503787856004303802       1993                        eng d00aEcology of mast-fruiting in three species of North American deciduous oaks0 aEcology of mastfruiting in three species of North American decid  c1993  a528-5410 v743 aWe conducted an 8-yr study of flower and acorn production in three species of oak in east-central Missouri (USA): white oak (Quercus alba), red oak (Q. rubra), and black oak (Q. velutina). The goal was to evaluate whether mast -fruiting, the synchronous production of large seed crops followed by small seed crops, is simply a response to weather conditions or is actually an evolved reproductivity strategy. In this paper, we address four specific questions: (1) Are annual fluctuations in acron crop size the result of synchronous production of acorns by individuals? (2) Are large acorn crops the result of large flower crops and/or high survival of those flowers to mature fruit? (3) To what extent do weather variables account for variation in acorn production among years? (4) Does acorn crop size correlate negatively with prior acorn production? Red oak and white oak showed a greater degree of mast -fruiting than did black oak. Within a species, individuals tended to produce large acorn crops in the same years, but each species differed in which years they produced large crops. The size of a given acorn crop was determined by both flower abundance and survival of flowers to fruit. Principal components and multiple-regression analyses were used to describe the relationship between weather variables and acorn production. The first principal component explained the largest amount of the variation in black oak (R-2 = 0.55) and red oak (R-2 = 0.89). In white oak, two principal components combined to explain 77% of the variation in acorn production. The weather variables that were associated with these principal components included spring temperature (positive effect) and summer drought (negative effect). Past acorn production had a major impact on the size of the current acorn crop, with each species showing a different pattern. In black oak, the current acorn crop was negatively correlated with the crop 3 yr prior but positively correlated with the crop 2 yr prior. In red oak, acorn crop size 1, 2, and 3 yr prior had negative correlations with current acorn crop, while acorn crop size 4 yr prior was positively correlated. In white oak, there were negative correlations between acorn crop size and crop size 1, 2, and 4 yr prior but a positive correlation with the acorn crop size 3 yr prior. These data are consistent with the hypothesis that mast-fruiting species must store resources during some years in order to produce a mast crop. We discuss the possibility that these three species may have inherent cycles of reproduction that are modified by the impact of weather conditions, black oak with 2-yr cycles, white oak with 3-yr cycles, and red oak with 4-yr cycles. We conclude that the patterns of acorn production for black oak, red oak, and white oak are not simply responses to weather events but are also a function of prior reproductive events. This suggests that masting is an evolved reproductive strategy.10a(Fagaceae-)10a[26070-] Fagaceae-10aACORN-CROP-SIZE10aAngiospermae-10aClimatology-: Environmental-Sciences10aDicots-10aDicotyledones-10aDROUGHT-10aEcology-: Environmental-Sciences10aFagaceae-: Angiosperms-10aFLOWER-ABUNDANCE10aMissouri-: USA-10aNearctic-region10aNorth-America10aPhysiology-10aPlantae-10aPlants-10aQuercus-alba (Fagaceae-)10aQuercus-rubra (Fagaceae-)10aQuercus-velutina10aReproduction-10aREPRODUCTIVE-STRATEGY10aSpermatophyta-10aSpermatophytes-10aTEMPERATURE-10aUSA-: North-America10aVascular-Plants10aWEATHER-1 aSork, V.-L.1 aBramble, J.1 aSexton, O.  uhttps://quercus.myspecies.info/node/7903254nas a2200493   4500008004100000245012000041210006900161260000900230300001400239490000700253520179700260653002302057653001802080653001802098653002602116653001202142653001902154653002802173653002202201653002202223653002002245653001802265653001302283653001202296653002002308653004402328653005402372653002502426653003802451653002102489653001902510653002002529653001902549653000902568653002002577100001602597700001702613700001802630700001702648700001602665700002302681700001302704856004302717       2002                        eng d00aPollen movement in declining populations of California Valley oak, Quercus lobata: Where have all the fathers gone?0 aPollen movement in declining populations of California Valley oa  c2002  a1657-16680 v113 aThe fragmented populations and reduced population densities that result from human disturbance are issues of growing importance in evolutionary and conservation biology. A key issue is whether remnant individuals become reproductively isolated. California Valley oak (Quercus lobata) is a widely distributed, endemic species in California, increasingly jeopardized by anthropogenic changes in biota and land use. We studied pollen movement in a savannah population of Valley oak at Sedgwick Reserve, Santa Barbara County, to estimate effective number of pollen donors (Nep) and average distance of effective pollen movement (delta). Using TWOGENER, our recently developed hybrid model of paternity and genetic structure treatments that analyses maternal and progeny multilocus genotypes, we found that current Nep = 3.68 individuals. Based on an average adult density of d = 1.19 stems/ha, we assumed a bivariate normal distribution to model current average pollen dispersal distance (delta) and estimated delta = 64.8 m. We then deployed our parameter estimates in spatially explicit models of the Sedgwick population to evaluate the extent to which Nep may have changed, as a consequence of progressive stand thinning between 1944 and 1999. Assuming that pollen dispersal distance has not changed, we estimate Nep was 4.57 individuals in 1944, when stand density was 1.48. Both estimates indicate fewer effective fathers than one might expect for wind-pollinated species and fewer than observed elsewhere. The results presented here provide a basis for further refinements on modelling pollen movement. If the trends continue, then ongoing demographic attrition could further reduce neighbourhood size in Valley oak resulting in increased risk of reproductive failure and genetic isolation.10a[26070-] Fagaceae-10aadult-density10aAngiospermae-10adeclining-populations10aDicots-10aDicotyledones-10aFagaceae-: Angiosperms-10agenetic-isolation10ahuman-disturbance10aNearctic-region10aNorth-America10aPlantae-10aPlants-10apollen-movement10aPopulation-Genetics: Population-Studies10aQuercus-lobata (Fagaceae-): California-Valley-oak10areproductive-failure10aSanta-Barbara-County: California-10aSedgwick-Reserve10aSpermatophyta-10aSpermatophytes-10aTWOGENER-model10aUSA-10aVascular-Plants1 aSork, V.-L.1 aDavis, F.-W.1 aSmouse, P.-E.1 aApsit, V.-J.1 aDyer, R.-J.1 aFernandez-M, J.-F.1 aKuhn, B.  uhttps://quercus.myspecies.info/node/5602293nas a2200133   4500008004100000245014100041210006900182260000900251300001200260520181300272100001602085700001502101856004302116       2002                        eng d00aGenetic differentiation of two california red oak species, Quercus parvula var. shreveii and Q. wislizeni, based on AFLP genetic markers0 aGenetic differentiation of two california red oak species Quercu  c2002  a417-4263 aOaks are renowned for posing problems in defining species boundaries. One example is the case of the interior live oak complex that is usually taken to include two varieties of Quercus wislizeni from the Coast Ranges of California and the Sierra Nevada, and Q. parvula var. shreveii from the central coast of California. The latter taxon was separated from Q. wislizeni, and was recognized in The Jepson Manual, but still is not fully accepted, since its morphological separation is ambiguous. In an attempt to test differentiation of these two taxa, molecular genetic analysis was carried out using Amplified Fragment Length Polymorphism (AFLP) markers. A total of 202 individuals from 19 populations including Q. parvula var. shreveii, Quercus wislizeni, Q. kelloggii and Q. agrifolia were analyzed. Four primer sets generated 311 polymorphic band classes. Although species-specific markers were observed between Q. kelloggii and other members of the red oak group in California, fixed genetic differences were not apparent among Q. agrifolia, Q. parvula var. shreveii and Q. wislizeni. Cluster analysis and principal coordinate analysis revealed low levels of genetic differentiation among coast live oak, interior live oak and shreve oak. Cluster analysis also suggested that Q. agrifolia populations are more similar to populations of Q. parvula var. shreveii than to coastal populations of Q. wislizeni. This may reflect the relatively short time since divergence of these species. On the other hand, repetitive hybridization and introgression may have acted as a homogenizing factor for these genetic markers. The relatively high genetic similarity between Q. agrifolia and Q. parvula var. shreveii may have implications for the management of Sudden Oak Death in the limited range of the latter taxon.1 aKashani, N.1 aDodd, R.S.  uhttps://quercus.myspecies.info/node/5001063nas a2200217   4500008004100000245015500041210006900196260000900265300001200274490000800286520036400294100002000658700001500678700001400693700001800707700001300725700001400738700001500752700001600767856006200783       2009                        eng d00aAge Structure and Genetic Diversity of Four Quercus macrocarpa (Michx.) Populations in Fragmented Oak Savanna along the Central Minnesota River Valley0 aAge Structure and Genetic Diversity of Four Quercus macrocarpa M  c2009  a301-3120 v1613 aOnly 0.02% of historic oak savanna exists today. To provide management recommendations, we characterized age-class structure, measured cover of competing tree species and estimated genetic variation within and among four Quercus macrocarpa Michx (bur oak) populations in the Minnesota River Valley. At each site, few middle-aged bur oaks existed, most were 901 aKittelson, P.M.1 aPinahs, C.1 aDwyer, J.1 aIngersoll, A.1 aMans, E.1 aRieke, J.1 aRutman, B.1 aVolenec, M.  uhttp://www.bioone.org/doi/abs/10.1674/0003-0031-161.2.301