A Trap for Insects Emerging from the Soil

1957 ◽  
Vol 89 (10) ◽  
pp. 455-456 ◽  
Author(s):  
W. J. Turnock

The larch sawfly, Pristiphora erichsonii (Htg.), overwinters in a cocoon in the ground and has an adult emergence period that may last two months. Ecological studies of this insect require information on the number of adults emerging and the seasonal pattern of emergence. Several types of open-bottomed screen emergence cages without traps were tested but the insects caught in such cages were difficult to remove. Also, many of the adults were lost in the vegetation unless the cages were visited more frequently than was practicable. The trap described here, attached to a screen cage, eliminates the objections given above and could be of use to persons interested in insects which emerge from the soil.

1966 ◽  
Vol 98 (7) ◽  
pp. 768-777 ◽  
Author(s):  
W. G. H. Ives ◽  
L. D. Nairn

AbstractThe effects of fluctuating water tables on the survival of the larch sawfly, Pristiphora erichsonii (Hartig) (Hymenoptera: Tenthredinidae), were studied by burying cocoons at different depths in a tamarack bog. Most larvae in cocoons flooded during August or September died before winter. The percentage of overwintering survival of unflooded cocoons remained constant from late fall until development began in the spring. The higher the cocoons were above the maximum water table during August and September, the greater was the percentage of overwintering survival and subsequent adult emergence.


1972 ◽  
Vol 104 (8) ◽  
pp. 1307-1312 ◽  
Author(s):  
R. J. Heron

AbstractDistinct differences were observed in postdiapause development and prolonged diapause of the larch sawfly, Pristiphora erichsonii (Hartig), obtained from the vicinity of Tazin River, Northwest Territories; near Riverton, Manitoba; and near Renovo, Pennsylvania. All populations had been reared under controlled laboratory conditions (21°±0.5 °C, 50±10% relative humidity, and a 15-hr daily photophase) for two or more generations.After 280 days cold treatment at 3°±1 °C, cocoons were dissected and the number of pronymphs and eonymphs was determined. Insects from each population were then reared at 5°, 10°, and 15 °C. Times to adult emergence, duration of individual stages, and numbers remaining in prolonged diapause at each temperature were determined.The most significant differences occurred among populations reared at 5 °C. At this temperature, the times to adult emergence and the duration of individual stages of development and the proportions remaining in prolonged diapause or arrested development, increased from northern to southern latitudes. Less significant population differences were noted at 10° and 15° than at 5 °C.


Author(s):  

Abstract A new distribution map is provided for Pristiphora erichsonii (Htg.) (Hymenopt., Tenthredinoidea) (Larch Sawfly). Hosts: Larix spp. Information is given on the geographical distribution in EUROPE (excl. USSR), Austria, Britain, Czechoslovakia, Denmark, Finland, France, Germany, Ireland, Netherlands, Norway, Poland, Rumania, Sweden, ASIA (excl. USSR), Japan, USSR, NORTH AMERICA, Canada, U.S.A.


1959 ◽  
Vol 91 (8) ◽  
pp. 496-500 ◽  
Author(s):  
W. G. H. Ives ◽  
R. M. Prentice

The Forest Insect Survey at the Forest Biology Laboratory, Winnipeg, has been compiling records for a number of years on the percentage of cocoons of the larch sawfly, Pristiphora erichsonii (Htg.), parasitized by the tachinid Bessa harveyi Tnsd. Sawfly cocoons were collected each fall from the soil in infested stands, and those containing living larvae were dissected to determine the percentage of parasitism by B. harveyi. These estimates have been used to provide an index of parasitism (Lejeune and Hildahl, 1954), but are of limited value for a number of reasons: (1) estimates can be expressed only as percentage of sound cocoons parasitized; (2) total parasitism cannot be estimated because a portion of the parasites emerge from the cocoons before collection; and (3) estimates of parasitism may not be representative of the stand because there is a tendency to collect cocoons where they are easiest to find; hence all the cocoons in a collection may be from one or two small areas. If the proportion of cocoons containing B. harveyi varies within a stand such collections may give unreliable estimates of parasitism.


1959 ◽  
Vol 91 (9) ◽  
pp. 535-542 ◽  
Author(s):  
C. H. Buckner

The relationship between the fate of cocoons of the larch sawfly, Pristiphora erichsonii (Htg.), and distance from small-mammal tunnels was studied during 1958 in the Whiteshell Forest Reserve of eastern Manitoba. The objects were to determine the distance that small mammals can detect cocoons and to observe possible effects of the interactions of small-mammal predation and other natural mortality factors of the insect. Additional analyses of the data provided information on the behaviour of the predators and the ecology of the prey insect.


1977 ◽  
Vol 109 (4) ◽  
pp. 597-603 ◽  
Author(s):  
Claude Alauzet

AbstractThe maximal emergence of Pissodes notatus (F.) adults takes place during July and August. It results from the different evolution of two populations:— a first population, whose complete development (from egg to adult) takes 11 or 12 months. This population corresponds to eggs laid after the middle of July (maximum egg laying during September). Most of the larvae having reached the third instar, it shows no more evolution during the winter; the further development takes place during the next spring, and adults emerge from mid-June to mid-July.— a second population resulting from egg laying, between February and July, of hibernated adults (maximum egg laying during April and May). The whole development being very short (2 to 3 months), the adults, corresponding to these eggs, emerge from the middle of July to the end of August.The observed differences between durations of the under-bark development (from 2 to 12 months) appear free of diapause and probably result from rates of development changing with temperature and instar.In our regional field temperature conditions, all the individuals reach finally their under-bark development approximatively at the same time, so that the adult emergence period takes place in July and August.


1968 ◽  
Vol 100 (5) ◽  
pp. 470-475 ◽  
Author(s):  
R. J. Heron

AbstractLarvae of the larch sawfly, Pristiphora erichsonii (Htg.), were fed foliage of tamarack, Larix laricina (Du Roi) K. Koch, treated with solutions of the vital dyes, Nile blue sulphate, rhodamine B, and coriphosphine O, to determine their suitability as markers. Coriphosphine O was highly toxic at the concentrations administered but successful tagging was obtained with the other two dyes. Optimal dye retention and survival were obtained when larvae were fed for 3 days early in the last stadium using Nile blue sulphate and throughout the last stadium using rhodamine B.Both dyes persisted throughout development and were incorporated in the cocoons and the oviposited eggs. They could be readily seen in all stages except for the cocoons and for eggs that contained rhodamine B. The dyes could be detected in cocoons by treating them with cold KOH followed by ethanol. The presence of rhodamine B in the eggs could be ascertained by its yellow fluorescence in ultraviolet.The dyes incorporated in the cocoons are relatively stable and laboratory tests indicate they probably can withstand weathering under normal field conditions over a 1-year period.The use of these dyes for internal marking should prove useful in studying adult dispersal and flight range and as a technique for use in population studies of the larch sawfly.


Sign in / Sign up

Export Citation Format

Share Document