Observations on fungi associated with spruce budworm infested balsam fir needles

1985 ◽  
Vol 15 (5) ◽  
pp. 896-901 ◽  
Author(s):  
J. David Miller ◽  
D. Strongman ◽  
N. J. Whitney
Keyword(s):  
Growth Rate ◽  
Spruce Budworm ◽  
Balsam Fir ◽  
Toxic Effects ◽  
Freeze Dried ◽  
Phylloplane Fungi ◽  
Conifer Needle

Fungi (ca. 2000 isolates) were isolated from balsam fir needles infested by the spruce budworm (Choristoneurafumiferana Clem.) as well as from uninfested needles. Most of the isolates were well-known colonizers of the conifer needle phylloplane. However, approximately 6% of the isolates obtained from the infested needles were unusual needle phylloplane fungi and some of these were toxigenic and (or) pathogenic. Some isolates (23) associated with the needles, frass, and larvae were cultured; solvent extracts of the freeze-dried material of some of these were cytotoxic to HeLa 229 cells. The isolates showing cytotoxicity were grown and the resulting hyphae were incorporated (1%, w/w) into a spruce budworm diet. Hyphae from several isolates in these diets resulted in slower growth rate and mortality. The results of this study show that the presence of the spruce budworm altered the phylloplane mycoflora and the data suggest that there are toxic effects to spruce budworm that consume phylloplane fungi.

Mechanism relating cambial electrical resistance to periodic growth rate of balsam fir

1983 ◽  
Vol 13 (3) ◽  
pp. 472-480 ◽  
Author(s):  
Robert O. Blanchard ◽  
Walter C. Shortle ◽  
Weston Davis
Keyword(s):  
Growth Rate ◽  
New Hampshire ◽  
Electrical Resistance ◽  
Spruce Budworm ◽  
Probable Mechanism ◽  
Potassium Content ◽  
Balsam Fir ◽  
Periodic Growth ◽  
Cambial Zone

Cambial electrical resistance (CER) and periodic growth rate (PGR) of canopy balsam fir (Abiesbalsamea L.) trees were determined on 26 sites in Maine, New Hampshire, and Vermont, U.S.A., varying in level of spruce budworm defoliation. Determinations of water and potassium concentrations were made of the bark, wood, and vascular cambial zone (VCZ). Low CER was associated with high PGR and vice versa. A decline in PGR on all 26 sites was detected during early 1970's to late 1970's. It was not associated with, but may have been exacerbated by, spruce budworm defoliation. The most probable mechanism relating CER to PGR in balsam fir was variation in the thickness of VCZ and its correlation with potassium content. Thicker VCZ of faster growing trees released more potassium into the solution contacting electrodes than thinner VCZ of slower growing trees.

Réduction de croissance en volume occasionnée au sapin baumier, suite à la défoliation par la tordeuse des bourgeons de l'épinette

1985 ◽  
Vol 61 (1) ◽  
pp. 10-13 ◽  
Author(s):  
Louis Archambault ◽  
Jean Beaulieu
Keyword(s):  
Growth Rate ◽  
Choristoneura Fumiferana ◽  
Volume Growth ◽  
Abies Balsamea ◽  
Spruce Budworm ◽  
Balsam Fir ◽  
Diameter Growth ◽  
Ottawa River ◽  
Epidemic Period ◽  
Growth Loss

A method was developed to determine the growth losses in volume in surviving balsam fir following a spruce budworm outbreak that occurred in the Ottawa River Valley in Quebec. Equations expressing the diameter growth rate had there been no infestation were developed. These equations were applied to balsam fir surviving the epidemic so as to determine what their diameters would have been without defoliation. Subsequently, the theoretical volumes were assessed using these diameters. The method was validated for the pre-epidemic period and precision was superior to 90%. Analyses revealed the outbreak caused a 49% volume growth loss to balsam fir for a period of approximately 10 years. Key words: Spruce budworm (Choristoneura fumiferana (Clem.)), balsam fir (Abies balsamea (L.) Mill.), growth losses.

Toxic Effects of Quinalphos on Protein Content and Growth Rate in Freshwater Teleost, Cyprinus carpio (L.)

2016 ◽  
Vol 23 (1) ◽  
pp. 89
Author(s):  
A. Padmanabha ◽  
H. R. V. Reddy ◽  
N. B. Shridhar ◽  
Muttappa Khavi ◽  
B. T. Naveen Kumar
Keyword(s):  
Growth Rate ◽  
Protein Content ◽  
Cyprinus Carpio ◽  
Toxic Effects ◽  
Freshwater Teleost

scholarly journals Predicting balsam fir mortality in boreal stands affected by spruce budworm

2021 ◽  
Vol 496 ◽  
pp. 119408
Author(s):  
Djidjoho Julien Houndode ◽  
Cornelia Krause ◽  
Hubert Morin
Keyword(s):  
Spruce Budworm ◽  
Balsam Fir

Weather and Outbreaks of the Spruce Budworm in the Province of Quebec from 1939 to 1956

1961 ◽  
Vol 93 (2) ◽  
pp. 118-123 ◽  
Author(s):  
J. G. Pilon ◽  
J. R. Blais
Keyword(s):  
Choristoneura Fumiferana ◽  
Abies Balsamea ◽  
Spruce Budworm ◽  
Balsam Fir ◽  
The Past ◽  
Forest Regions ◽  
Tree Component ◽  
Gaspe Peninsula ◽  
Gaspé Peninsula

Nearly all forest regions in the Province of Quebec where balsam fir (Abies balsamea (L.) Mill.) is an important tree component have been subjected to severe defoliation by the spruce budworm, Choristoneura fumiferana (Clem.), during the past 20 years. These outbreaks have followed an easterly direction beginning near the Ontario-Quebec border in 1939 and ending in the Gaspé Peninsula in 1958.

The influence of hardwood content on balsam fir defoliation by spruce budworm

1996 ◽  
Vol 26 (9) ◽  
pp. 1620-1628 ◽  
Author(s):  
Qiong Su ◽  
Ted D. Needham ◽  
David A. MacLean
Keyword(s):  
New Brunswick ◽  
Natural Enemies ◽  
Spruce Budworm ◽  
Balsam Fir ◽  
Generalized Model ◽  
Stand Management ◽  
Working Hypothesis ◽  
Model Combining

Changing stand composition by increasing hardwood content has been suggested as a long-term method for reducing susceptibility and vulnerability of balsam fir (Abiesbalsamea (L.) Mill.) to spruce budworm (Choristoneurafumiferana (Clem.)). Twenty-five mixed balsam fir–hardwood stands were selected in northern New Brunswick, with five stands in each 20% hardwood class (0–20, 21–40%, etc.). Defoliation each year from 1989 to 1993 was significantly (p < 0.0001) related to hardwood content, with r2 ranging from 0.57 to 0.81. As hardwood content increased, defoliation of balsam fir decreased. From 1989 to 1992, the years of moderate to severe defoliation, balsam fir stands with <40% hardwoods sustained 58–71% defoliation, on average, versus 12–15% defoliation in stands with >80% hardwood. A generalized model combining hardwood content and the estimated defoliation in pure softwood stands in a given year explained 77% of the variation in defoliation over stands and years. This study indicated that mixed balsam fir–hardwood stand management, with hardwood content >40%, could substantially reduce losses during spruce budworm outbreaks. Further research is warranted to elucidate the mechanism involved, but our working hypothesis is that greater hardwood content increased the diversity or populations of natural enemies such as birds and parasitoids.

Prescribed Burning for Stand Conversion in Budworm-killed Balsam Fir: An Ontario Case History

1986 ◽  
Vol 62 (2) ◽  
pp. 96-100 ◽  
Author(s):  
D. J. McRae
Keyword(s):  
Fuel Consumption ◽  
Prescribed Burning ◽  
Choristoneura Fumiferana ◽  
Abies Balsamea ◽  
Spruce Budworm ◽  
Fire Spread ◽  
Fire Effects ◽  
Balsam Fir ◽  
Prescribed Burn ◽  
Stand Conversion

Recent spruce budworm (Choristoneura fumiferana [Clem.]) infestations have resulted in widespread areas of balsam fir (Abies balsamea [L.] Mill.) mortality in Ontario, and there is growing interest in reestablishing these areas quickly as productive forests. One technique being used is prescribed fire after a salvage and bulldozer tramping operation. A 445-ha prescribed burn was carried out under moderate fire danger conditions in northern Ontario. The site, which was covered by balsam fir fuel that had been killed by spruce budworm, was tramped to improve fire spread. Weather, fuel consumption, and fire effects are reported. The burn effectively reduced heavy surface fuel loadings and consequently planting on the site was easier. Key words: Prescribed burning, fire, spruce budworm. Choristoneura fumiferana, balsam fir, Abies balsamea, fuel consumption, site preparation, tramping, stand conversion.

Metabolites toxic to spruce budworm from balsam fir needle endophytes

1992 ◽  
Vol 96 (4) ◽  
pp. 281-286 ◽  
Author(s):  
Larry A. Calhoun ◽  
John A. Findlay ◽  
J. David Miller ◽  
Norman J. Whitney
Keyword(s):  
Spruce Budworm ◽  
Balsam Fir

LONG TERM STUDY OF THE EFFECTIVENESS OF AERIAL APPLICATION OF BACILLUS THURINGIENSIS – ACEPHATE COMBINATIONS AGAINST THE SPRUCE BUDWORM, CHORISTONEURA FUMIFERANA (LEPIDOPTERA: TORTRICIDAE)

1977 ◽  
Vol 109 (9) ◽  
pp. 1239-1248 ◽  
Author(s):  
O. N. Morris
Keyword(s):  
Bacillus Thuringiensis ◽  
Choristoneura Fumiferana ◽  
Larval Mortality ◽  
Abies Balsamea ◽  
Spruce Budworm ◽  
White Spruce ◽  
Balsam Fir ◽  
Population Densities ◽  
Long Term Study

AbstractBacillus thuringiensis (Dipel® 36B) mixed with a sublethal concentration of acephate (Orthene®) (O, S-dimethyl acetylphosphoramidothioate), an organophosphorous insecticide, was applied at 2.35–14 l./ha to white spruce (Picea glauca) and balsam fir (Abies balsamea) trees infested with spruce budworm, Choristoneura fumiferana (Clem.). The treatment rate was 20 Billion International Units of B. thuringiensis (B.t.) activity with or without 42 g of active ingredient of acephate/ha.The ground deposit of the standard Dipel wettable powder formulation was 12% of emitted volume compared with 21–32% for the Dipel 36B flowable. The viability of B.t. spores was drastically reduced after 1 day of weathering but a high level of biological activity by the spore–crystal complex persisted for up to 20 days post-spray due probably to crystal activity.The addition of about 10% of the recommended operational rate of acephate to the B.t. suspension increased larval mortality by 34% when applied at 4.7 l./ha. Reductions in budworm populations were 97–99% in B.t. + acephate plots and 86–90% in B.t. alone plots.Plots with moderate budworm densities of up to 27 larvae/100 buds on white spruce and 36/100 on balsam fir were satisfactorily protected from excessive defoliation in the year of spray by B.t. with or without acephate. Plots with higher population densities were not satisfactorily protected based on the branch sample examination but aerial color photographs indicated good protection to the top third of the trees. Population declines were greater and defoliation and oviposition were lower in the treated plots than in the untreated checks 1 year later without further treatment. Two years later the larval population densities in all plots were low but the density was twice as high in the untreated check as in the treated plots, indicating long term suppression by the treatments. Defoliation was negligible in all plots.The treatments had no deleterious effect on spruce budworm parasitism. The data indicate that the integrated approach using Bacillus thuringiensis – chemical pesticide combinations is a viable alternative to the use of chemical pesticides alone in spruce budworm control. Large scale testing is now warranted.

Natural variation in balsam fir foliar components of dietary importance to spruce budworm

1977 ◽  
Vol 7 (1) ◽  
pp. 47-53 ◽  
Author(s):  
G. G. Shaw ◽  
C. H. A. Little
Keyword(s):  
Population Dynamics ◽  
Natural Variation ◽  
Spruce Budworm ◽  
Balsam Fir ◽  
Total Sugars ◽  
Caloric Value ◽  
Seasonal Trends ◽  
Geographical Variations ◽  
Foliar Concentrations ◽  
Foliar Concentration

Year-to-year, geographical, and local variations in foliar concentrations of crude fat, nitrogen, total sugars, and starch and in foliar caloric value were determined for maturing, current-year needles of balsam fir (Abiesbalsamea L.). All except geographical variations proved to be statistically significant. Seasonal trends of chemical concentrations in maturing needles were in agreement with previous findings.Much of the variation in foliar caloric value could be explained by changes in foliar concentration of crude fat.Year-to-year changes in foliar nutrients may influence spruce budworm population dynamics.

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