Swaine Jack-Pine Sawfly in Wisconsin

1953 ◽  
Vol 46 (4) ◽  
pp. 703-703 ◽  
Author(s):  
Daniel M. Benjamin ◽  
Norbert B. Underwood
Keyword(s):  
1958 ◽  
Vol 36 (2) ◽  
pp. 175-183 ◽  
Author(s):  
A. W. Ghent

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.


1963 ◽  
Vol 41 (2) ◽  
pp. 227-235 ◽  
Author(s):  
L. C. O'Neil

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.


1970 ◽  
Vol 46 (2) ◽  
pp. 126-133 ◽  
Author(s):  
J. M. McLeod

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.


1968 ◽  
Vol 44 (5) ◽  
pp. 14-20 ◽  
Author(s):  
J. M. McLeod

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.


1962 ◽  
Vol 94 (8) ◽  
pp. 809-818 ◽  
Author(s):  
H. A. Tripp

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).


1976 ◽  
Vol 108 (11) ◽  
pp. 1137-1144 ◽  
Author(s):  
J. N. All ◽  
D. M. Benjamin

AbstractAntifeedants for controlling larval feeding of several Neodiprion sawflies were evaluated in laboratory and field studies. Nine commercially available insect antifeedants and a hexane extract of the juvenile foliage of jack pine, Pinus banksiana Lambert, were tested on larvae of six species. In laboratory bioassays larvae exhibited varying sensitivity to antifeedants; generally species with monophagous or restricted oligophagous feeding habits were most sensitive. In the laboratory the Swaine jack pine sawfly, Neodiprion swainei Middleton, had severely restricted feeding, development, survival, and fecundity. Triphenyltin hydroxide was toxic to N. swainei and to European pine sawfly, N. sertifer (Geoffroy). In field tests certain antifeedants disrupted N. swainei feeding and development. The colonial behavior of larvae often was disrupted and solitary larvae fell from trees or wandered on twigs. Colony disruption by most antifeedants was temporary and many larvae resumed feeding.


1966 ◽  
Vol 98 (8) ◽  
pp. 789-794 ◽  
Author(s):  
J. G. Pilon

AbstractThe life -span of Swaine jack-pine sawfly adults was studied under various constant and alternating temperatures and at four different values of relative humidity. Temperature significantly influenced the life-span of both sexes according to a non-linear equation, and relative humidity according to a linear regression. The influence of temperature varied with relative humidity in the case of males but not in the case of females. The life-span of both sexes was shorter at alternating temperatures than at constant temperatures.


1966 ◽  
Vol 98 (4) ◽  
pp. 430-447 ◽  
Author(s):  
J. M. McLeod

AbstractInsight into the source of aggregation in the spatial distribution of cocoons of the Swaine jack-pine sawfly, Neodiprion swainei Middleton was gained by the use of special techniques enabling the sampling of units of forest floor in contiguous 2 × 2-inch square samples, as well as by randomized one-square-foot samples taken over a larger area. It was concluded that cocoon distribution is initially random but marked aggregation results from the subsequent transportation of cocoons into feeding stations by predacious small mammals, mostly of the genus Sorex. The feeding stations tended to be distributed near decaying stems and stumps on the forest floor, a factor which augmented the extent of aggregation. Of cocoons not preyed upon by small mammals, slightly higher counts were recorded directly under crown canopies as opposed to open areas, at a tree density of approximately 920 per acre.


1964 ◽  
Vol 96 (4) ◽  
pp. 589-599 ◽  
Author(s):  
G. C. Becker ◽  
D. M. Benjamin

AbstractThe Swaine jack-pine sawfly, Neodiprion swainei Midd., is a serious defoliator of jack pine in Canada, and has been reported widely in the Lake States. The largest populations in Wisconsin were on plantations and windbreaks. It is host specific and feeds primarily on old foliage. Damage to new foliage is sporadic, usually being heaviest late in the season. When forced to feed on red, eastern white, or Scotch pines the sawfly develops abnormally. It is not a serious threat to these species. In southern Wisconsin, adults emerge during June; eggs are present from mid-June to mid- July; larvae feed during July and August; heaviest feeding damage occurs in late July and early August; late larval populations feed throughout September. Fecundity was 116 ± 17 eggs. Eggs are placed in new needles, and "paired eggs" are characteristic. The distribution pattern of eggs within a single cluster is characterized for long and for short shoots of new growth. Female larvae require five or six feeding instars, males five. Phenological observations are correlated with sawfly development.


1952 ◽  
Vol 84 (2) ◽  
pp. 59-61
Author(s):  
A. S. West

Leconte's sawfly or the red-headed pine sawfly (Neodiprion lecontei Fitch) is a common insect attacking pines in Ontario. Plantations red pine are almost invariably attacked from the time the trees have reached two to four feet in height. Periodically epidemic populations cause significant damage. The life history and habits of the species have heen described by Middleton (2) who states that this insect attacks practically all species of pine as bell as larch. Schaffner (3) also indicates that the larvae feed on a wide variety of pine and occasionally on other conifers. Red pine (Pinus resinosa Ait.) is undoubtedly the usual host, although in Ontario jack pine (Pinus banksiana Lamb.) is sometimes attacked. In 1946 evidence was secured to show that jack pine needles may be selected for oviposition even in an area where red pine foliage is plentiful. (Figure 1).


Sign in / Sign up

Export Citation Format

Share Document