Showing papers on "Bark published in 1975"
105 citations
84 citations
Journal Article•
68 citations
TL;DR: It is concluded that NIT precedes formation of necrophylactic periderms (NP), may provide environment necessary for NP formation in tissues internally abutting NIT, and is a marker for distinguishing NP from exophylacticPeriderms.
Abstract: Impermeability to OSO4 of periderm-free zones around the feeding sites of balsam woolly aphid (BWA), Adelges piceae, in the bark of Abies, was caused by a non-suberized impervious tissue (NIT). NIT...
59 citations
TL;DR: From the root bark of Nauclea latifolia several indoloquinolizidine alkaloids were isolated, two are known compounds: angustine and angustoline and the other two are new products.
57 citations
TL;DR: In this article, four sesquiterpene lactones were obtained from L. tulipifera; two germacranolides, lipiferolide (4 ) and epitulipinolide diepoxide (5 ) from the leaves, an elemanolide, epitulo-denoide (7 ), and an eudesmanolate, γ-liriodenolide from the root bark.
52 citations
TL;DR: Using explosives, 93 grand fir trees were examined for root decay and bark beetle activity and it appears that root disease is an important factor in predisposing fir to attack by bark beetles.
Abstract: Using explosives, 93 grand fir were examined for root decay and bark beetle activity. Ninety-six per cent of the trees attacked by bark beetles also had root rot. From the data it appears that root disease is an important factor in predisposing fir to attack by bark beetles. Significant relationships were found between the presence of root decay and both the incidence of beetle attack and the number of attacks. No such relationship could be found concerning the success of beetle attacks. The question of bark beetles as vectors of root disease was not considered.
47 citations
TL;DR: Nitrogen reserves were found mainly to be in the protein fraction of both wood and bark, and it appears that arginine and the supplementary amino acids and amides may also make up a nitrogen reserve, especially in wood.
Abstract: SummaryNitrogen levels were measured in 1-year-old shoot wood and bark of 2-year-old Golden Delicious apple trees from January to April. Nitrogen reserves were found mainly to be in the protein fraction of both wood and bark. These reserves were hydrolysed in mid-late March resulting in a rapid increase in the soluble nitrogen levels for use in growth. Prior to hydrolysis of protein there appeared to be a significant amount of soluble nitrogen present especially in wood. Arginine composed 8-17 % of the total free amino fraction in bark and 20-30 % in wood. It appears that arginine and the supplementary amino acids and amides may also make up a nitrogen reserve, especially in wood.
45 citations
TL;DR: About 90% of the gypsy moth, Porthetria dispar (L.) pupae found in a series of sparse stable populations studied between 1965 and 1968 were either beneath bark flaps or in the litter, where female pupae had a reasonable survival probability.
Abstract: About 90% of the gypsy moth, Porthetria dispar (L.) pupae found in a series of sparse stable populations studied between 1965 and 1968 were either beneath bark flaps or in the litter. Male larvae were more likely to pupate in bark flaps than females. Pupal survival was usually higher among pupae beneath bark flaps than among those in the litter, and bark flaps provided virtually the only pupation locations in the whole environment, within the highest density stratum studied, where female pupae had a reasonable survival probability. Adult gypsy moth production in these populations could be accurately estimated from knowledge of pupal density and sex ratio, and the number of bark flaps per 0.01-acre. Bark flap removal is suggested as a potentially useful technique for preventing outbreaks.
40 citations
TL;DR: In this article, the pyrolysis of native jack pine bark has been studied from 200 to 340°C by thermogravimetric (TG), and isothermal weight-loss methods.
Abstract: The pyrolysis of native jack pine bark has been studied from 200 to 340°C by thermogravimetric (TG), and isothermal weight-loss methods. The effects of particle size, solvent extraction and additions of zinc (II) and iron (III) chlorides on the pyrolysis behaviour have also been examined. The bark was characterized by infrared spectroscopy and low-temperature gas adsorption. Residues were analysed for CHN contents and structural changes which occurred on heating were examined by optical and scanning electron microscopy. The TG characteristics were not affected by solvent extraction or particle size variation while the metal chloride additions inhibited the loss of volatile materials from the bark probably by stabilizing chemical bonding in the bark components. Isothermal decomposition data were found to fit established kinetic expressions associated with inorganic decompositions. The physical mechanics of pyrolysis have been interpreted on the assumption that pyrolysis is initiated through the formation of planes of lateral strain which are sites for decomposition and which decrease in number inversely with time. It is suggested that these sites are produced by an oxidation mechanism which may be rate-controlling in the pyrolysis. This hypothesis is supported by the observation that the data fit a reaction rate compensation curve, often associated with oxidation processes but more generally with heterogeneous catalytic reactions. The compensation curve also relates the kinetic parameters found by other workers for a large variety of wood-derived materials.
34 citations
01 Nov 1975
TL;DR: Ethereal extracts prepared from the larvae, pupae, or eggs of 10 species of insects and from various parts of 343 species of higher plants were screened for juvenilizing effects against Tenebrio molitor and Oncopeltus fasciatus.
Abstract: Ethereal extracts prepared from the larvae, pupae, or eggs of 10 species of insects and from various parts of 343 species of higher plants were screened for juvenilizing effects against Tenebrio molitor and Oncopeltus fasciatus. Activity in both species was shown by an extract of the larvae of the stable fly, Stomoxys calcitrans, whereas an extract of the pupae was active in O. fasiatus only. Extracts of two plant species (Echinacea angustifolia roots and Chamaecyparis lawsoniana seeds) showed high juvenilizing activity in T. MOLITOR, AND EXtracts of five plant species (Clethra alnifolia stems, leaves, and fruits, Sassafras albidum roots and root bark, Eucalyptus camaldulensis stems and bark, Pinus rigida twigs and leaves, and Iris douglasiana roots, stems, and fruits) were highly active in O. fasciatus an extract of Tsuga canadensis leaves showed lower activity in this insect. Extracts of 16 species of plants showed high insecticidal activity (mortality) in O. fasciatus but lacked juvenilizing properties in both species of test insects.
TL;DR: In this article, the constituents of the bark, timber and seeds of Mesua thwaitesii were examined by column chromatography and GC-MS, and several 4-phenylcoumarins including mammeigin, mesuagin and mesuol were identified in the seed extract.
TL;DR: In this paper, a 10% urea spray was used on Golden Delicious apple trees in both January and February to increase the total nitrogen in the leaves of the trees, due mainly to an increase in protein nitrogen.
Abstract: SummaryFollowing the application of urea sprays in October on Golden Delicious apple trees, increased amounts of nitrogen were translocated from the leaves into storage tissues. Trees receiving 10% urea spray had significantly higher levels of total nitrogen in bark in both January and February than either those receiving soil application or control treatments. However, there was also a significant increase in total nitrogen in bark from January to February in the sprayed trees, due mainly to an increase in protein nitrogen in January. In February the soluble nitrogen increased while the protein remained constant. There were no significant differences between treatments in wood total nitrogen levels in January. In February the trees receiving the 10% urea spray had significantly higher total nitrogen levels than those receiving either the soil application or control treatments. In the sprayed trees there was an increase in wood total nitrogen from January to February due to an increase in soluble nitrogen...
TL;DR: Sitosterol and the following terpenic compounds have been isolated from the bark of Podocarpus lambertius: 3β-hydroxytotarol, 4β-carboxynortol, and macrophyllic and lambertic acids as mentioned in this paper.
01 Jan 1975
TL;DR: From the bark of Calophyllum cordato-oblongum thw. as discussed by the authors the new resin acid, cordatooblongic acid (Ia) was isolated and identified as 3-(6,7-dihydro-5-hydroxy-2,2,trans-7,8-tetramethyl-6-oxo-2H,8H-benzo[1,2-b:5,4-b′]-dipyran-10-yl)butyric acid.
Abstract: From the bark of Calophyllum cordato-oblongum Thw. the new resin acid, cordato-oblongic acid (Ia) was isolated and identified as 3-(6,7-dihydro-5-hydroxy-2,2,trans-7,8-tetramethyl-6-oxo-2H,8H-benzo[1,2-b:5,4-b′]-dipyran-10-yl)butyric acid. The timber extract contained the known xanthones 2-hydroxyxanthone (VIII), scriblitifolic acid (X), 1,5,6-trihydroxyxanthone (VIIb), 1,6-dihydroxy-5-methoxyxanthone (VIIa), and jacareubin (XV), and the two new xanthones 3-hydroxy-4-methoxyxanthone (IXa) and cordato-oblonguxanthone (XIII){identified as 1,2-dihydro-6-hydroxy-3,3-dimethylpyrano[2,3-a]xanthen-12(3H)-one}. Friedelin and β-sitosterol were isolated from both extracts.
Journal Article•
Journal Article•
TL;DR: From the bark extract of Kayea stylosa Thw., taraxerol (Ia), simiaren-3β-ol (IIa), betulinic acid (III), β-sitosterol, and the new xanthones 10-O-methylmacluraxanthone {12-(1, 1-dimethylprop-2-enyl)-5, 9-dihydroxy-10-methoxy-2, 2-dimmethyl-2H-pyrano[2, 3-d]xanthen-
Abstract: From the bark extract of Kayea stylosa Thw., taraxerol (Ia), simiaren-3β-ol (IIa), betulinic acid (III), β-sitosterol, and the new xanthones 10-O-methylmacluraxanthone {12-(1,1-dimethylprop-2-enyl)-5,9-dihydroxy-10-methoxy-2,2-dimethyl-2H-pyrano[3,2-b]xanthen-6-one}(IVa) and kayeaxanthone {11-(1,1-dimethylprop-2-enyl)-9-hydroxy-8,10-dimethoxy-2,2-dimethyl-2H-pyrano[2,3-d]xanthen-7-one}(VIIIa) have been isolated and their structures established. The timber extract contained only 1,3,5-trihydroxy-2-methoxyxanthone (VIa) and β-sitosterol.
TL;DR: The bark anatomy of Pinus radiata D. Don, P. nigra Arnold, and Pseudotsuga menziesii is described andStructural variability and the presence of dark-coloured polyphenols ar...
Abstract: The bark anatomy of Pinus radiata D. Don, P. nigra Arnold, and Pseudotsuga menziesii (Mirb.) Franco is described. Inner bark is composed of sieve cells, axial parenchyma, and rays. In P. menziesii it also contains fibres. In all species axial parenchyma is abundant. Some axial parenchyma cells have crystals which are more numerous in P. radiata and P. menziesii than in P. nigra. Horizontal resin canals are present but axial canals are absent. Outer bark or rhytidome is composed of alternating bands of periderm and dead phloem. Phelloderm is better developed in P. radiata and P. nigra than in P. menziesii. The boundary between phelloderm and the preceding phloem is poorly defined. Three types of phellem cell occur in P. nigra. Phellem in P. menziesii displays “growth zones”. Crystals are present in some phellem cells in P. nigra and P. menziesii. Dead phloem consists of cells which are distorted and crushed to varying degrees. Structural variability and the presence of dark-coloured polyphenols ar...
TL;DR: A screening program using suspensions of ground bark in mineral salts media, or extracts prepared from ground bark by treating with hot water, sulfuric acid, ammonium hydroxides, or sodium hydroxide, yielded more than 200 pure cultures of fungi, yeasts, and bacteria, most of which were filamentous fungi.
Abstract: A screening program using suspensions of ground bark in mineral salts media, or extracts prepared from ground bark by treating with hot water, sulfuric acid, ammonium hydroxide, or sodium hydroxide, yielded more than 200 pure cultures of fungi, yeasts, and bacteria. Only 38 of these gave good growth on liquid bark media. All were filamentous fungi, although many bacteria and yeasts were among the cultures that failed to give appreciable growth. Species of Penicillium, Scopulariopsis, Aspergillus, Trichoderma, Cladosporium, and Fusarium were among the most actively growing cultures. Cell biomass yields, as measured by cell nitrogen determinations, were too low for economic production of single cell protein.
TL;DR: In this article, a triterpenoid of the oleanoic acid type was shown to be 3β-hydroxy 6α-acetoxy oleaneic acid from the bark of Betula utilis.
TL;DR: The stereostructure of michelanugine (6a-H as β and 7-OH as α) has been elaborated with the help of PMR and rotational data.
TL;DR: From the extractive of the bark of Libocedrus formosana Florin, sugiol (I), lignoceric acid, 6α-hydroxy-7-oxo-ferruginol (II), ferruginOL (III), xanthoperol (IV), β-sitosterol, a mixture of hydrocarbons, a long chain ester and three unidentified products, A, B and C, were isolated as discussed by the authors.
Abstract: From the acetone extractive of the bark of Libocedrus formosana Florin, sugiol (I), lignoceric acid, 6α–hydroxy–7–oxo–ferruginol (II), ferruginol (III), xanthoperol (IV), β–sitosterol, a mixture of hydrocarbons, a long chain ester and three unidentified products, A, B and C, were isolated.
TL;DR: The bark of Nauclea parva contains several alkaloids, the most abundant of which, parvine, is of the corynanthe-type as mentioned in this paper, and its synthesis from harmalan and nicotinoyl chloride is described.
01 Jan 1975
TL;DR: In the Sangre de Cristo mountain range of New Mexico, chlorophyll concentrations are inversely correlated (p =.001) with altitude as mentioned in this paper, indicating that higher elevations have higher cortical chlorophyl concentrations.
Abstract: A bstract. Although quaking aspen (Populus tremuloides Michx.) bark appears greener at higher elevations in the Sangre de Cristo mountain range of New Mexico, chlorophyll concentrations are inversely correlated (p = .001) with altitude. The higher concentration of chlorophyll at lower elevations is effectively masked by a white bloom of dead periderm cells which is also characteristic of exposed site trees. At higher elevations the bloom is yellowbrown and more translucent, thus allowing the chlorophyll layers beneath to show through. Therefore, trees at higher elevations appear greener even though they have lower cortical chlorophyll concentrations. The altitudinal gradient in bark reflectance characteristics may be of adaptive value. If cortical photosynthesis is more important at higher elevations, the translucent bloom would be advantageous in making more light available for photosynthesis. Increased light absorbtion might also be important in raising bark temperatures for physiological activity during the winter months. At lower elevations where air temperatures are higher, the highly reflective bloom may protect the trees from high bark temperatures and sunscald.
TL;DR: Hortia badinii (Rutaceae) contains rutecarpine and hortiacine in the bark, as well as coumurrayin, methyl 3-[2-methoxy-6′, 6′-dimethylpyrano(2′,3′:3,4)phenyl]-propionate, 3]-2,6-dimethoxy 6′,6′]-propionic acid in the wood, and methyl 3 [2,4-dimethyltimethylphenyl] 2.