Potential for pheromone-baited traps to predict seed loss caused by Contarinia oregonensis (Diptera: Cecidomyiidae)

2002 ◽  
Vol 134 (5) ◽  
pp. 689-697 ◽  
Author(s):  
P. Morewood ◽  
W.D. Morewood ◽  
R.G. Bennett ◽  
G. Gries
Keyword(s):  
United States ◽  
Pseudotsuga Menziesii ◽  
Late Summer ◽  
Early Spring ◽  
Douglas Fir ◽  
Washington State ◽  
Gall Midges ◽  
Seed Loss ◽  
Baited Traps ◽  
Positive Correlations

AbstractIn seed orchards of Douglas-fir, Pseudotsuga menziesii (Mirbel) Franco (Pinaceae), located in Washington State and Oregon, United States, we tested whether catches of male Douglas-fir cone gall midges, Contarinia oregonensis Foote, in pheromone-baited traps can be used to predict the extent of galled scales (= seed loss at harvest) caused by developing larvae. In 2000, 27 experimental blocks (4–7 ha each) were selected. In each block we recorded mean numbers of (i) male C. oregonensis captured in 20 pheromone-baited Wing traps, (ii) egg-infested scales in up to 50 conelets in early spring, and (iii) galled scales in up to 50 cones in late summer. In 2001, the experiment was repeated with 20 Delta traps in each of 26 experimental blocks. Moreover, catches of C. oregonensis and nontarget insects in Delta traps and Wing traps were compared in one additional orchard block in 2001. In both years there were positive correlations between mean numbers of egg-infested and galled scales and between mean numbers of captured male C. oregonensis and mean numbers of both egg-infested and galled scales, particularly when only experimental blocks with ≥50% of trees bearing at least 5 conelets were considered. Our results suggest that 4 or 2 captured male C. oregonensis in Wing or Delta traps, respectively, warrant insecticidal control of C. oregonensis. Delta traps, which captured fewer nontarget insects, would be more suitable than Wing traps for operational implementation of this technology.

scholarly journals Infection of Select Pinaceae and Cupressaceae Seedlings to Phytophthora pinifolia

2019 ◽  
Vol 20 (2) ◽  
pp. 106-111
Author(s):  
Timothy L. Widmer ◽  
Stephen C. Dodge
Keyword(s):  
United States ◽  
At Risk ◽  
Pseudotsuga Menziesii ◽  
Loblolly Pine ◽  
Pinus Radiata ◽  
Pinus Elliottii ◽  
The United States ◽  
Douglas Fir ◽  
Important Species ◽  
Monterey Pine

Phytophthora pinifolia caused a devastating disease on Monterey pine (Pinus radiata) in Chile. This pathogen has not been reported in the United States, but there is concern should it arrive. There is little information regarding other hosts besides Monterey pine that may be susceptible to this pathogen. In the present study, other potential hosts within the Pinaceae and Cupressaceae were inoculated with zoospores of P. pinifolia and observed for symptoms and infection after 4 weeks. Similar to Monterey pine, knobcone (Pinus attenuata), bishop (P. muricata), and ponderosa (P. ponderosa) pines were highly infectious, whereas several important species such as loblolly pine (P. taeda) and Douglas fir (Pseudotsuga menziesii) showed no infection. P. pinifolia was also not recovered from slash (Pinus elliottii) and eastern white (P. strobus) pines. This study is important because it demonstrates other economically important tree hosts are at risk by P. pinifolia, should it enter the United States.

AIR-BORNE POLLEN SURVEYS IN BRITISH COLUMBIA

1967 ◽  
Vol 47 (3) ◽  
pp. 251-261 ◽  
Author(s):  
I. J. Bassett ◽  
C. W. Crompton
Keyword(s):  
United States ◽  
British Columbia ◽  
North America ◽  
Late Summer ◽  
The United States ◽  
Early Spring ◽  
Causative Agents ◽  
Early Fall ◽  
Trees And Shrubs

Results from 17 pollen collecting stations in British Columbia indicate that air-borne pollen of ragweeds and their relatives, the principal causative agents of hay fever in North America, is practically absent throughout the province. Coniferous trees and shrubs such as pines, spruces, firs, cedars, Douglas fir, hemlocks and junipers produce the greater part of the air-borne pollen from March to early July. Pollen from alders, poplars, willows and birches is also prevalent in some areas in the early spring. The peak periods of grass pollen near the United States–Canadian border occur mainly in June and the early part of July, while further north they are about a month later. Of the four types of plantain pollen identified from the different collecting stations, English plantain was the most common, especially in the southwesterly part of the province. Pollen from the lambs’-quarters and amaranth families and wormwoods occurs mainly in the late summer and early fall and is more abundant in the dry interior than along the coast.

Three New Species of Contarinia Rond. (Diptera: Cecidomyiidae) in Douglas-Fir Needles

1961 ◽  
Vol 93 (2) ◽  
pp. 123-130 ◽  
Author(s):  
S. F. Condrashoff
Keyword(s):  
United States ◽  
New Species ◽  
Host Range ◽  
Douglas Fir ◽  
United States Bureau ◽  
Plant Quarantine ◽  
Gall Midges ◽  
Insect Identification ◽  
Three New Species ◽  
Northern Idaho

Felt (1940) mentioned a midge in Douglas-fir needles which he called Cecidomyia sp.; this reference was quoted by Barnes (1951). Denton (1954) reported that a midge, identified by the Division of Insect Identification, United States Bureau of Entomology and Plant Quarantine as Cecidomyia sp., occurred in needles of Douglas fir in northeastern Washington, northern Idaho, and northeastern Montana. In 1954 the author reared some adults which H. F. Barnes (in litt. 1957) referred to the genus Contarinia Rond. Unpublished records from 1935 to date indicate unidentified needle-inhabiting gall midges throughout most of the host range. Recently the author found indications of a species comples which were confirmed by further rearings of adults. This paper presents the description of three new species of Contarinia Rond., reared under similar conditions, from material obtained at Oyama, B.C.

RESOURCE USE AND CLONAL DIFFERENCES IN ATTACK RATE BY THE DOUGLAS-FIR SEED CHALCID, MEGASTIGMUS SPERMOTROPHUS WACHTL (HYMENOPTERA: TORYMIDAE), IN FRANCE

1991 ◽  
Vol 123 (6) ◽  
pp. 1219-1228 ◽  
Author(s):  
Nancy Rappaport ◽  
Alain Roques
Keyword(s):  
United States ◽  
Pseudotsuga Menziesii ◽  
Resource Use ◽  
Attack Rate ◽  
Management Strategies ◽  
Douglas Fir ◽  
Analysis Of Covariance ◽  
North Central ◽  
Lepidopteran Species ◽  
Potential Impact

AbstractThe within-cone distribution of Megastigmus spermotrophus Wachtl (Hymenoptera: Torymidae), the Douglas-fir seed chalcid, infesting Douglas-fir [Pseudotsuga menziesii (Mirb.) Franco] cones from north-central France was compared with that in samples from California. Results indicate that the mid-region of cones was more intensively utilized by seed chalcids in France than in California, whereas in the northwestern United States the mid-region is characteristically occupied by dipteran and lepidopteran species. This difference in distribution may explain the large discrepancy in infestation rates on the two continents. The potential impact of this finding on pest management strategies is discussed.Cones were measured and dissected or X-rayed to determine seed chalcid infestation levels. Analysis of covariance performed on data from cones that were collected in 1986 and dissected showed cone diameter at maturity to be a highly significant factor in attack rate, although slopes were different among clones. Between-tree variation was also significant, but clonal source was not. Cone diameter, clonal source, and between-tree variation constituted 87.1% of the variation in rate of attack by the seed chalcid. Although clone was not a significant factor in data from dissected cones, X-rayed cones showed significant differences in attack rates for some clones.

Salmonberry and salal annual aerial stem production: the maintenance of shrub cover in forest stands

2001 ◽  
Vol 31 (9) ◽  
pp. 1629-1638 ◽  
Author(s):  
John C Tappeiner, II ◽  
John C Zasada ◽  
David W Huffman ◽  
Lisa M Ganio
Keyword(s):  
Pseudotsuga Menziesii ◽  
Early Spring ◽  
Douglas Fir ◽  
Annual Production ◽  
Stem Density ◽  
Shrub Cover ◽  
Forest Stands ◽  
Gaultheria Shallon ◽  
Aerial Stem ◽  
Stem Production

Annual sprouting of aerial stems and ramets enables populations of salmonberry (Rubus spectabilis Pursh), salal (Gaultheria shallon Pursh), and probably other forest shrubs to maintain dense covers (>20 000 stems/ha). We studied annual stem production of salmonberry on cut (all stems cut within 15 cm of the ground) and uncut (stems were not treated) plots for 8 years and salal for 5 years in the understories of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), alder, and riparian stands, as well as clearcuts, which are all common stand types in western Oregon. Mean salmonberry stem production on uncut plots ranged from 4.7 stems·m–2·year–1 (95% CI 2.9–7.4) in alder stands and clearcuts to 1.6 stems·m–2·year–1 (95% CI 1.0–2.6) in conifer stands. Mean salal production was greater, ranging from 58 stems·m–2·year–1 (95% CI 25–135) to 8.6 stems·m–2·year–1 (95% CI 3.7–20.1) on uncut plots in clearcuts and unthinned Douglas-fir stands, respectively. Annual production of both species was somewhat greater on cut plots. Most stems produced in early spring die by December, but enough are recruited to replace mortality of older stems. Stem density was maintained for 8 years for salmonberry and 5 years for salal on both cut and uncut plots. Based on length of rhizomes and bud density we estimate that only 1–5% of the buds in the rhizomes are needed to support this annual stem production. Although these species sprout vigorously after their aerial stems are killed, disturbance is not necessary for maintaining a dense cover. It appears that, once established, salal, salmonberry, and probably other clonal forest shrubs can maintain a dense cover that can interfere with establishment of trees and other shrubs in canopy gaps or other openings.

Description and Habits of a New Species of Phytophaga (Diptera: Cecidomyiidae) from Western Red Cedar Cones

1959 ◽  
Vol 91 (11) ◽  
pp. 719-723 ◽  
Author(s):  
A. F. Hedlin
Keyword(s):  
New Species ◽  
Pseudotsuga Menziesii ◽  
Douglas Fir ◽  
Thuja Plicata ◽  
Gall Midges ◽  
Red Cedar ◽  
Western Red Cedar ◽  
A New Species

Gall midges have been reported from cones of western red cedar, Thuja plicata Donn., but none have been described. Keen (1958) reported the occurrence in Washington and Oregon of a cone midge which was credited with destroying 90 per cent of the seed. In 1940 Prebble and Graham reported a midge in cones of western red cedar at Cowichan Lake, B.C. These reports almost certainly refer to the midge described here. The only other species taken from red cedar cones was Lestodiplosis taxiconis Foote, but it occurred in verysmall numbers; previously it has been reported only from cones of Douglas fir, Pseudotsuga menziesii (Mirb.) Franco (Foote, 1956).

Bionomics of Three Closely Related Species of Contarinia Rond. (Diptera: Cecidomyiidae) from Douglas-fir Needles

1962 ◽  
Vol 94 (4) ◽  
pp. 376-394 ◽  
Author(s):  
S. F. Condrashoff
Keyword(s):  
British Columbia ◽  
Pseudotsuga Menziesii ◽  
Related Species ◽  
Douglas Fir ◽  
General Reference ◽  
Closely Related Species ◽  
Gall Midges ◽  
Christmas Trees

Incidence of damage to needles of Douglas fir, Pseudotsuga menziesii (Mirb.) Franco, by larvae of gall midges has been noted in British Columbia since 1935. In 1953 severe midge damage to Douglas fir occurred in sections of British Columbia, Washington, Idaho and Montana. Outside of brief and general reference to these gall midges in literature and in unpublished notes, almost nothing was known of their biology, and the species remained undescribed. Relatively little interest has been shown these insects until recent years, when severe infestations in southeastern British Columbia affected the sale of Douglas fir for use as Christmas trees.

Site temperatures influence seasonal changes in terpene composition in Douglas-fir vegetative buds and current-year foliage

2003 ◽  
Vol 33 (11) ◽  
pp. 2269-2273 ◽  
Author(s):  
Jason R Nault
Keyword(s):  
Pseudotsuga Menziesii ◽  
Seasonal Changes ◽  
Geographic Location ◽  
Early Spring ◽  
Douglas Fir ◽  
Bornyl Acetate ◽  
Degree Day ◽  
Vegetative Buds ◽  
Temperature Regimes

Over a 3-year period (1998–2000), variations in terpene composition was measured in vegetative buds of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) from six sites varying in elevation and geographic location with sampling from early spring to midsummer. Eleven terpenes were found in virtually all samples (tricyclene, α-pinene, camphene, sabinene, β-pinene, myrcene, Δ-3-carene, limonene, β-phellandrene, terpinolene, and bornyl acetate) and represented an average of 87% of the total terpenes. In each year, composition of the terpene mix varied significantly (P [Formula: see text] 0.05) for all sites and dates, with some significant site and date interactions. Degree-day accumulations were calculated for all sites and years. Patterns of change in terpene composition between sites, areas, and years were strongly related to the temperature regimes associated with site and year.

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