Showing papers on "Bark published in 1981"
TL;DR: Large populations of nitrogen-fixing bacteria were found with the bark beetle, although no in situ acetylene reduction was demonstrated, which suggests a symbiotic relationship.
Abstract: Nitrogen-fixingEnterobacter agglomerans andEnterobacter spp. were consistently isolated from the bark beetleDendroctonus terebrans. Large populations of nitrogen-fixing bacteria were found with the beetle, although no in situ acetylene reduction was demonstrated. The constant occurrence of nitrogenfixing bacteria withD. terebrans suggests a symbiotic relationship. Nitrogen-fixing bacteria were also isolated from the bark beetlesDendroctonus frontalis andIps avulsus.
95 citations
TL;DR: In this article, a survey was undertaken in S.W. England to study epiphyte differentiation between free-standing oak (Quercus petraea) and ash (Fraxinus excelsior) trunks.
Abstract: A survey was undertaken in S.W. England to study epiphyte differentiation between free-standing oak (Quercus petraea) and ash (Fraxinus excelsior) trunks. Epiphyte cover was measured on 23 trees in 87 15×15 cm quadrats positioned on the north, east, south and west faces of each trunk at a height of 1.52 m. Measurements of 20 environmental factors were made at each quadrat position. Analysis of the vegetation data by reciprocal averaging showed that floristic variation is continuous and corresponds only partially to phorophyte identity. Rank correlation coefficients were calculated between the floristic axis obtained by reciprocal averaging, and individual environmental factors including a variate, obtained by principal components analysis of the environmental data, which expressed the major differences between the oak and ash environments. The most significant correlation was obtained with bark pH. Values of bark pH for oak and ash samples overlapped considerably although the mean for ash (5.1) is higher than for oak (4.7). It is concluded that the epiphytic flora is responding to variations in bark acidity or some closely related factor and not to other, closely phorophyte dependent nutritional factors. Factors influencing bark acidity in oak and ash are briefly discussed.
63 citations
38 citations
25 Dec 1981
29 citations
TL;DR: In this paper, 95% ethanol was sprayed at the rate of approximately 46 ml/m2 of bark surface on the lower 1 or 2 m of standing living spruce trees, Picea engelmannii Parry and P. glauca (Moench) Voss hybrid population, 23 of 47 and 18 of 19 treated trees in two areas received one to many spruce beetle, Dendroctonus rufipennis (Kirby), attacks, whereas only 2 of 63 and 2 of 64 untreated trees, respectively were attacked.
Abstract: When 95% ethanol was sprayed at the rate of approximately 46 ml/m2 of bark surface on the lower 1 or 2 m of standing living spruce trees, Picea engelmannii Parry – P. glauca (Moench) Voss hybrid population, 23 of 47 and 18 of 19 treated trees in two areas received one to many spruce beetle, Dendroctonus rufipennis (Kirby), attacks, whereas only 2 of 63 and 2 of 64 untreated trees, respectively, were attacked. Some of the treated trees were killed by mass attacks of the beetles, but most trees pitched out the attacks. Thus beetle attacks on essentially resistant trees were induced by the ethanol treatment. However, spruce beetles were not attracted by the ethanol treatment.
28 citations
TL;DR: Among the three South American Lauraceae with cinnamon odours, Ocotea quixos Lam.
28 citations
28 citations
TL;DR: Evidence was obtained which indicates that cytokinins are apparently both produced and utilised at low temperatures, and it would appear that their production occurs in the bark and that they are utilised within the buds.
25 citations
01 Dec 1981
TL;DR: In this article, pine bark chips were used as carbon source in mixed liquid cultures of cellulolytic and lignin degrading strains of Bacillus and Cellulomonas to achieve pine bark delignification.
Abstract: Delignification of pine bark chips was observed after about 35 days when they were the sole carbon source in mixed liquid cultures of cellulolytic and lignin degrading strains of Bacillus and Cellulomonas. No delignification was observed in pure cultures. Free tannins liberated from the chips were also degraded in most of the cultures. The necessity of combining a cellulolytic and lignin-degrading bacterial strain to obtain delignification is discussed.
25 citations
24 citations
TL;DR: Pentanortriterpenoids from Azadirachta indica A. Juss (Meliaceae) have been isolated for the first time from seed oil, leaves, and bark.
Abstract: Aus Samenol, Blattern und Rinde von Azadirachta indica A. Juss (Meliaceae) wurden erstmals Pentanortriterpenoide isoliert. Nimbinen (1a), 6-Desacetylnimbinen (1b), Nimbandiol (2a) und 6-O-Acetylnimbandiol (2b) finden sich im Samenol, 1a, b und 2a in den Blattern, 1a und b in der Rinde. Die Konstitutionen wurden NMR-spektroskopisch zugeordnet.
Pentanortriterpenoids from Azadirachta indica A. Juss (Meliaceae)
Pentanortriterpenoids have been isolated for the first time from seed oil, leaves, and bark of Azadirachta indica. Nimbinene (1a), 6-deacetylnimbinene (1b), nimbandiol (2a), and 6-O-acetylnimbandiol (2b) have been found in the seed oil, 1a, b and 2a in the leaves, 1a and b in the bark. The structure determination was carried out by NMR spectroscopy.
TL;DR: Volume and thickness of bark were studied for 32 species groups of British Columbia and the equation of Vb = a'HTbDBHcBTd is recommended for bark volume prediction.
Abstract: Volume and thickness of bark were studied for 32 species groups of British Columbia. Over 32,000 trees constituted the data base to derive bark volume equations. Because of its simplicity and good predictive power, the equation of Vb = a'HTbDBHcBTd is recommended for bark volume prediction. The possibility to develop bark taper equations and to estimate bark thickness at any given height above breast height were also investigated.
01 Jan 1981
01 Jan 1981
TL;DR: In this article, the results showed that the alcohol and water extracts contained simple polyphenols and their glycosides, tannins, mono-and disaccharides, soluble hemicelluloses and pectins.
Abstract: Successive extraction of the bark with solvents of increasing polarity yielded about 60% of soluble material. The alcohol and water extracts contained principally simple polyphenols and their glycosides, tannins, mono-and disaccharides, soluble hemicelluloses and pectins. Hot water extracts are suitable for production of adhesives by reaction with formaldehyde, but their polyphenol content is only 50%. The polyphenols and their glycosides, and glucosides of hydroxystilbenes, were investigated in detail.
TL;DR: In this article, eleven triterpenes with the lanostene-type skeleton were isolated from the benzene extract of western white pine bark and their structures were determined mainly on the basis of physical and spectral data.
Abstract: Eleven new triterpenes with the lanostene-type skeleton were isolated from the benzene extract of western white pine bark. Their structures were determined mainly on the basis of physical and spectral data.
TL;DR: Shinjudilactone, a new bitter principle with a new 13 [12→11α]abeo-picrasane skeletone, was isolated from root bark of Ailanthus altissima SWINGLE and the structure was determined.
Abstract: Shinjudilactone, a new bitter principle with a new 13 [12→11α]abeo-picrasane skeletone, was isolated from root bark of Ailanthus altissima SWINGLE and the structure was determined.
TL;DR: Fresh Pinus radiata bark will impair the growth of seedlings and struck cuttings of some species but not of Monstera pertusa, Camellia sasanqua ‘Lucinda’, Rhodondendron ‘Sir Robert Peel’ or Pilea cadierei.
TL;DR: The extractives of Calophyllum tomentosum contain friedelin, friedelan-3β-ol, betulinic acid, taraxero, and betulinicity as mentioned in this paper.
TL;DR: The history and occurrence of the so-called bacterial canker of ash (Fraxinus excelsior), caused by Pseudomonas syringae subsp.
Abstract: The history and occurrence of the so-called bacterial canker of ash (Fraxinus excelsior), caused by Pseudomonas syringae subsp. savastanoi pv. fraxini1 are outlined. Symptoms of the disease and other forms of damage, such as Nectria-canker, damage by the ash bark beetle, Leperisinus varius and twig-mining by the ash bud moth, Prays fraxnella are discussed in detail.
01 Jan 1981
TL;DR: Bark beetles use aggregative pheromones to colonize temporary habitats where they feed, mate, and reproduce and offer exciting possibilities for pest suppression because they attract both sexes and because aggregation is essential for reproduction.
Abstract: Bark beetles (Scolytidae that feed on phloem and cambium) are a major pest of coniferous forests throughout the northern hemisphere (Rudinsky, 1962). Many bark beetle species use aggregative pheromones to colonize temporary habitats where they feed, mate, and reproduce (Wood, 1972; Borden, 1974). These pheromones offer exciting possibilities for pest suppression because they attract both sexes and because aggregation is essential for reproduction (Wood, 1972; Wood and Bedard, 1977).
TL;DR: Ten species of hymenopterous parasites were reared from logs of pine and cypress, naturally infested with 5 species of bark beetles, naturallyinfested with Orthotomicus erosusWoll.
Abstract: Ten species of hymenopterous parasites were reared from logs of pine and cypress, naturally infested with 5 species of bark beetles,viz., Orthotomicus erosusWoll.,Pityogenes calcaratusEichh., andTomicus destruensWoll. — on pine;Phloeosinus armatusReitt. andP. aubeiPerris — on cypress, in Israel.
TL;DR: A seasonal study of the cytokinin levels in different parts of young plants of Salix babylonica revealed that for a better understanding of the role of these hormones in plant growth it is essential that a more comprehensive approach must be adopted.
TL;DR: Two new glycosides from the stem bark of Prosopis juliflora have been characterized in this article, i.e., kaempferol 4′-methyl ether 3-O -β-d -galactopyranoside and retusin 7- O -neohesperidoside.
TL;DR: In this paper, the initial nitrogen desirable value (DV) to give maximum dry weight and maximum growth rate for various growing periods has been estimated for the 1: 1.5 water extraction procedure by regressing dry weights and net growth rate against soil test values using a quadratic function.
Abstract: The initial nitrogen desirable value (DV) to give maximum dry weight and maximum growth rate for various growing periods has been estimated for the 1: 1.5 water extraction procedure by regressing dry weight and net growth rate against soil test values using a quadratic function. The DV for dry weight and growth rate has been estimated for chrysanthemum and verbena (2 trials each) and for dry weight for tomato (1 trial) in a number of substrates. The DV for maximum dry weight of chrysanthemum, grown for 48 days under winter conditions, were: Peat 151–211 ppm and greater, Bark 140‐168 ppm and Peat and Sawdust and Sand (PSS) 135–162 ppm. Under summer conditions and grown for 35 days, the DV were as follows: Peat 134 — 172 ppm, Peat and Pumice (PP) 142 ‐170 ppm, Bark 168–202 ppm and PSS 152–172 ppm. The DV for maximum dry weight of verbena grown for 42 days under spring conditions were as follows: Peat 57 ppm, Bark 41 ppm and PSS 48–52 ppm and greater. Under summer conditions and grown for 38 days, t...
TL;DR: Calozeylanic acid has been isolated from the bark of three calophyllum species: C.lankaensis, C.thwaitesii and C.walkeri.