Oviposition Behaviour of the Jack-pine Sawfly, Neodiprion americanus banksianae Roh., as Indicated by an Analysis of Egg Clusters

1955 ◽  
Vol 87 (6) ◽  
pp. 229-238 ◽  
Author(s):  
A. W. Ghent
Keyword(s):  
Jack Pine ◽  
Egg Laying ◽  
Oviposition Behaviour ◽  
Pine Sawfly ◽  
Large Numbers ◽  
Measurement And Analysis ◽  
Full Complement ◽  
Group Feeding ◽  
Indirect Information ◽  
Larval Group

This study was undertaken as part of a broader investigation of the behaviour of the jack-pine sawfly, Neodiprion americanus banksianae Roh. The greater part of the investigation was directed towards an understanding of larval group-feeding behaviour, but in order to clarify the situation in which this insect begins larval life, large numbers of egg clusters were analysed with special attention paid to the positional relations of egg-bearing needles. Such analysis has permitted certain inferences on the oviposition behaviour of this insect and this indirect information is of value in view of the difficulties experienced in efforts to induce this species to oviposit under laboratory conditions for direct observation. Fortunately, egg clusters obtained from the field are well adapted to descriptive measurement and analysis, for in order to lay its full complement of eggs the adult female sawfly must select as many as 20 to 30 needles, thus leaving behind it a readily measured record of its egg-laying behaviour.

Oviposition of the Red-Headed Pine Sawfly, Neodiprion lecontei (Fitch)

1960 ◽  
Vol 92 (6) ◽  
pp. 430-435 ◽  
Author(s):  
K. J. Griffiths
Keyword(s):  
Pinus Banksiana ◽  
Jack Pine ◽  
Oviposition Behaviour ◽  
Pine Sawfly ◽  
Important Group ◽  
Neodiprion Lecontei ◽  
Cast Doubt ◽  
The Subject ◽  
European Pine Sawfly

The oviposition behaviour of Neodiprion sawflies has been the subject of much investigation in recent years. The impetus for this interest seems to lie in the paper by Atwood and Peck (1943), in which it was suggested that the number and spacing of eggs on needles were a useful tool for the identification of memhers of this important group of conifer defoliators. Ghent (1955) has analysed the egg clusters of N. pratti banksianae Roh., and Ghent and Wallace (1958) have investigated the behaviour responsible for the pairing of eggs on adjacent jack pine (Pinus banksiana Lamb. ) needles by N. swainei Midd. More recently, Ghent (1959) has presented a study of the factors determining the spacing of eggs by the European pine sawfly, N. sertifer (Geoff.). Of these, the 1955 and 1959 papers, in addition to making valuable contributions to our understanding of the behaviour of adults, cast doubt on the usefulness of the number and spacing of eggs as identifying characters in these species.

STUDIES OF THE FEEDING ORIENTATION OF THE JACK PINE SAWFLY, NEODIPRION PRATTI BANKSIANAE ROH.

1958 ◽  
Vol 36 (2) ◽  
pp. 175-183 ◽  
Author(s):  
A. W. Ghent
Keyword(s):  
Jack Pine ◽  
Pine Sawfly ◽  
Underlying Mechanisms

The heads of feeding larvae of the jack pine sawfly are consistently oriented towards the needle tips. This orientation is not obtained from the apically-directed needle teeth, and is found to be independent of gravity and of the flexibility of the foliage. Though light can act to disrupt the orientation, larvae adopt the orientation in darkness so that light cannot be postulated as an essential directive stimulus. The behavior is identified as a "free-end" response, and possible underlying mechanisms are discussed.

Swaine Jack-Pine Sawfly in Wisconsin

1953 ◽  
Vol 46 (4) ◽  
pp. 703-703 ◽  
Author(s):  
Daniel M. Benjamin ◽  
Norbert B. Underwood
Keyword(s):  
Jack Pine ◽  
Pine Sawfly

THE SUPPRESSION OF GROWTH RINGS IN JACK PINE IN RELATION TO DEFOLIATION BY THE SWAINE JACK-PINE SAWFLY

1963 ◽  
Vol 41 (2) ◽  
pp. 227-235 ◽  
Author(s):  
L. C. O'Neil
Keyword(s):  
Pinus Banksiana ◽  
Radial Growth ◽  
Jack Pine ◽  
Growth Rings ◽  
Cross Sectional ◽  
Pine Sawfly ◽  
Young Stand ◽  
The Dead ◽  
Dense Stand

An investigation of the radial growth of jack pine (Pinus banksiana Lamb.) defoliated by the Swaine jack-pine sawfly (Neodiprion swainei Midd.) disclosed that growth rings were discontinuous and missing in cross-sectional disks from severely damaged trees. In young and open-grown trees with dead tops, the incidence of such deficiencies in radial growth was especially high in disks from upper regions of the stems, in the vicinity of the dead tops; radial growth was suspended for 1 year and subsequently resumed in disks from the lower regions of some stems. Cambial inactivity was more generalized in trees from an old and dense stand and it was detected in disks representing major portions of some of the stems sampled; the death of some trees followed 2 to 6 years of cambial inactivity in disks cut at various heights along their entire stems. Growth deficiencies in the young stand were clearly effects of severe sawfly defoliation. Data from the old, dense stand indicated that sawfly defoliation had perhaps merely hastened the gradual deterioration of the stand in which intertree competition was intense.

The Epidemiology of the Swaine Jack-pine Sawfly, Neodiprion Swainei Midd.

1970 ◽  
Vol 46 (2) ◽  
pp. 126-133 ◽  
Author(s):  
J. M. McLeod
Keyword(s):  
Tree Mortality ◽  
Jack Pine ◽  
Pine Forests ◽  
Population Increase ◽  
First Year ◽  
Pine Sawfly ◽  
Jack Pine Forests ◽  
Commercially Important

Neodiprion swainei, a defoliating sawfly specific to jack pine, has destroyed thousands of acres of commercially important jack-pine forests in recent years. This sawfly can kill trees within 4 years of the start of a population increase. Outbreaks are usually found in foci in poorer jack-pine sites on outwash plains. Tree mortality occurs after complete defoliation of the previous years' foliage, combined with severe defoliation of the current year's foliage. Tree mortality starts in the first year after particularly severe defoliation and may be cumulative to 5 years; thus, detection of the insect in a stand should warrant increased watchfulness.Outbreaks may follow at intervals of about 8 years. Hazard areas for Quebec and Ontario are defined.

scholarly journals Results of an Aerial Spraying Operation Against the Swaine Jack Pine Sawfly, Neodiprion swainei Middleton, in Quebec utilizing the Insecticide Phosphamidon

1968 ◽  
Vol 44 (5) ◽  
pp. 14-20 ◽  
Author(s):  
J. M. McLeod
Keyword(s):  
Jack Pine ◽  
Pine Forest ◽  
Pine Sawfly ◽  
Aerial Spraying ◽  
One Year

In August 1965, 135,000 acres of jack pine forest in the St. Maurice Valley, Quebec, were sprayed with Phosphamidon for control of an outbreak of the Swaine jack pine sawfly, Neodiprion swainei Middleton. Applied by spray planes at a rate of 0.2 gallon per acre containing ¼ pounds of active insecticide material, it resulted in 99% mortality of the sawfly, and the threat of defoliation subsided. Phosphamidon applied at [Formula: see text] lb. per acre in a subsidiary test was almost as effective. One year after treatment, the sawfly population remained suppressed in the spray area, with no immediate prospect of resurgence. The treatment did not adversely affect the balance between the sawfly and its parasites, nor cause long-term instability in populations of other insects, birds and mammals living in the forest.

The distribution of the eggs of Mammalian Lice on their hosts. 2. Analysis of the Oviposition behaviour of Damalinia ovis (L)

1957 ◽  
Vol 5 (1) ◽  
pp. 19 ◽  
Author(s):  
MD Murray
Keyword(s):  
Temperature Gradient ◽  
Tactile Stimulus ◽  
Egg Laying ◽  
Oviposition Behaviour ◽  
Behaviour Pattern ◽  
Optimum Temperature ◽  
Depressant Effect ◽  
Temperature Zone ◽  
Stage 1 ◽  
Physical Features

The behaviour pattern of Damalinia ovis (L.) is adapted to the physical features of the environment in which the louse lives. In stage 1, the louse was attracted to temperatures between 35 and 40�C and this temperature zone was necessary for oviposition to proceed satisfactorily. Optimum temperature conditions were between 37 and 39�C. In stage 2, the louse orientated itself so that its head was directed towards the warm end of a temperature gradient or towards the saturated end of a humidity gradient, but when these gradients were antagonistic the orientation to temperature dominated. At the commencement of stage 3, the louse reversed its orientation to both temperature and humidity gradients but again the attraction to temperature was dominant. Before egg laying commenced, a fibre of suitable diameter had to be caught by a gonopod and held next to the abdomen. The resulting tactile stimulus was critical and its absence inhibited oviposition. Other factors which influenced oviposition were the depressant effect of high humidities, the orientation to light, and the attraction to other ovipositing lice and eggs.

Investigations on Trichogramma lutea, Gir., as a Parasite of the Cotton Bollworm, Heliothis obsoleta, Fabr.

1936 ◽  
Vol 27 (2) ◽  
pp. 219-235 ◽  
Author(s):  
F. S. Parsons ◽  
G. C. Ullyett
Keyword(s):  
Winter Season ◽  
Larval Survival ◽  
Egg Laying ◽  
Mortality Factors ◽  
Cool Season ◽  
Large Numbers ◽  
Typical Experiment ◽  
Egg Parasitism ◽  
Citrus Orchards ◽  
Low Degrees

Some of the problems involved in the estimation of parasitism in populations of Heliothis eggs are discussed:—(a) Effective parasitism of the “active fraction” of eggs as laid in situ is denned.(b) The habits of the egg-laying moth in point of the duration of oviposition on individual crops and diversion of moth activity from one host to another are discussed in relation to releases of Trichogramma lutea. Data are given on the distribution of bollworm eggs in a crop and associated factors.(c) Investigations on the dispersion of liberated parasites are described. Dispersion was found to be rapid and widespread; concerted activity by large numbers in given areas did not apply.Investigations in rain-grown crops are described and results are quoted from a typical experiment in maize, wherein the percentages of parasitism recorded in a large number of equal sections of the crop are regressed on proportionate larval survival. Although the egg parasitism ranged from 21·2 per cent, to 82·3 per cent., differences in larval populations were inappreciable. An explanation for this is offered in an analysis of the effect of various mortality factors.The parasite was relatively ineffective in cotton crops. The low degrees of parasitism found are assigned to the growth-habit of the plant, the scattered manner of egg deposition thereon and the impediment offered to the insect by the dense hair processes of the plant at many sites where eggs are commonly placed.Investigations on irrigated (cool season) market-garden crops and citrus orchards are described. These form the principal breeding sources of summer bollworm. Oviposition is extensive and sustained for three to four months on these crops, thereby affording opportunity for continuous parasite activity and the cumulative participation of progeny bred in the field. In nature Trichogramma lutea does not, however, appear until the latter end of the egg-laying by Heliothis and the authors were unable to establish laboratory-bred representatives at an earlier period.Another egg parasite, Phanurus ullyetti, is prevalent before Trichogramma appears and accomplishes much that was hoped for from the attempted earlier introduction of Trichogramma. In effect, the latter, as seen from diagrams furnished with the paper, becomes substituted for Phanurus toward the close of the winter season. It is probable that temperature is a determining factor in the biology of both parasites, although other causes for the observed relations are suggested.Further investigations are needed on the subject of exploiting T. lutea in the cool season.

The Relationship of Spathimeigenia spinigera Townsend (Diptera: Tachinidae) to its Host, Neodiprion swainei Midd. (Hymenoptera: Diprionidae)

1962 ◽  
Vol 94 (8) ◽  
pp. 809-818 ◽  
Author(s):  
H. A. Tripp
Keyword(s):  
Population Dynamics ◽  
Pinus Banksiana ◽  
Jack Pine ◽  
Immature Stages ◽  
Pine Sawfly ◽  
Factors Influencing ◽  
Form Part ◽  
Extensive Program ◽  
Relationship Of ◽  
The Relationship

Studies on the parasites of the Swaine jack pine sawfly, Neodiprion swainei Midd., form part of an extensive program designed to assess the factors influencing population dynamics of this important defoliator of jack pine, Pinus banksiana Lamb. Investigations were carried out in the Province of Quebec between 1955 and 1959 near the headwaters of the Gatineau River, Abitibi County, and continued during 1960 and 1961 near the source of the Vermillion River, County Laviolette. In both areas, one of the principal parasites associated with N. swainei was the tachinid, Spathimeigenia spinigera Townsend. Descriptions of the immature stages of this parasite, and details of its behaviour were published previously (Tripp, 1960).

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