22 .T . Ii:STO II 01.. Sill". BI:lT. C II I.I" .III :I.\ 7 1 (1~ j" - I ) , 0, T. J. 1974

OCClHHE:\CE OF LEAF ROLLERS (LEPIDOPTER .-\: ) A:\D THEIR I·-\R.\SITES L:\ THE Oh.A:\ ·\GA:\ '"ALLEY, BRITISH COLl\lBL\ D. F. M A YERl A 'J D B . P. BElHN E P est ology Cent re o D epa rtment o f Biological Sciences. Simon Fraser l ·ni\"e r, it y . Burnab\" 2. B rit i,;h C olumh ia

A KSTR ACT Se"en specie,; of leaf rol le rs feed on a pp le in t he Okanagan \ ·all ey. Fi"e o f t hem. including two of t he three most common species. were not pre­ viousl\" recorded as feeding on apple there. Six of t he species have a lt e rna t i"e host pla nts of which rm,e is t he most important. A short key t o fi na l inst a r la r\"ae of six of t he species is included . Thirt y-seven species of parasit es were reared . of wh ich eight may ha " e some sign ificance in control.

Introduction (a ) A rch i ps a1'gyrospilu s (Walk.) , Apple-feeding species of leaf rol­ th e fruit-tree leaf roller, has been the lers in the Okan agan Valley were in­ dominan t leaf roller on apple in th e vestigated in 1972. The speC ies, th eir Okanagan Valley since th e early food pla n ts, and their na tural enemies 1920 's. It was still dominan t in 1972 , are listed h ere; aspects of th eir ecol­ comprising from 19 to 99% of the ogy ar e discussed elsewhere (Mayer apple leaf rollers in differen t locali­ and Beirne, in press) . ties, alth ough it was exceeded in num­ The Leaf Rollers bers by A . 1' osanus and by Pan­ Seven species wer e found feeding cl em is limit ata in loca tions n ear Sum ­ on apple in th e Okanagan Valley, merla nd. Apple, followed by rose and between Kelowna and Okanagan antelope bush (Pu1'shia t r identata Falls. An earlier survey by Venables (Pursh) ) , are the primary host (1924) revealed four species of which plan ts. Oth er food plants are two were not found in the 1972 sur­ (Betula sp.) , squaw current (Ribes vey. All seven are univoltine. Archips ce1' eum Doug!.) , Oregon grape (Ma­ a1'gY1'ospilus and A . 1'osanus overwin­ honia n e1'vosa (Pursh)), Russian ter as eggs which hatch when apple olive (Elean gus angustijolia Pall.) , is in the one-half-inch green bud walnut (Juglans r egia L.), and stage of development. The newly­ (Salix sp.) . Feeding tests showed that hatch ed larvae disperse, often wind­ the larvae will feed on leaves of borne. The five other species overwin­ almost a ny avail able shrub or tree ter as larva e. All seven .species reduce rather than starve. This species is potential fruit set by feeding on the closely r ela ted to A. rosanus but re­ developing buds and leaves. Blossom peated la bora tory attempts to inter­ feeding is common. On a pple the larva breed them resulted in a single rolls a single leaf, often a ttach ed to ma ting but no eggs. Twenty species a fruit. On pla n ts with smaller leaves of paraSites were reared. such as privet two to five leaves may (b) A. 1'O sanus (L .) , the European co mpromise the n est. The seven leaf roller, was common ( 25 to 80 % ) species in approximate order of eco­ on apple in the Summerland district nomic significance to apple are as in 1972 but was not previously r ecord­ follows. ed on that plant in the Okanagan Valley. The usual primary host plant l'rt·. ... l ' lll ;Hld n ',...< J )l'P:lrllllt'1l1 III FI\II HIHd,,~\. \\ ,1... hill )! 14, 11 SL lTt, l niq·r ... it \', htllll1~lIl. \ \ ;l ... hill).!II'II. is privet (Ligustmm vulgare L.) . J. IC 'TI >lI O I.. S II ... HI: I I·. C"II ' \ I I :I \ 71 (1~171) , O"T. 1. 1974 23

Other primary hos t plants are rose the fall dead-leaf roller, was fo und and red -osier dogwood (Cornus sto­ only on apple (2% ) . It overwinters as lonifera Michx.) . It was also found a final-insta l' la rva, whereas the other feeding on (Alnus sp.), choke­ species that do not overwinter as cherry ( virginian a L.), h aw­ eggs do so as par tly-grown larvae. thorn (Crataegus doug lasi i Lind!.) , The majority of th e larvae were found (Acer sp.) , Russian olive, wal­ in living rolled leaves wh ereas in New nut, and willow. It was not fou nd York (Chapman and Lienk 1971) most feeding on currant though this is a of the larvae construct nes ts from host plant in Eas tern North America dead leaves or cause a living leaf to (Whitehead 1926) . Twenty - eight die by pa rtly severing the petiole. species of parasites were reared. (f) Choriston eura r osaceana (c) limitata ROb ., th e (Ha rr.), th e obli que - banded leaf three-lined leaf roller, was common roller, was th e dominant species on (2 to 42% ) on apple in the Summer­ apple in th e Okanagan Valley up to land district in 1972 though not re­ the 1920's (Venables 1924) but it is corded previously as feeding on it in now ra re. It was found in 1972 in a the OkanJ.gan Valley. Other primary single location near Okanagan Falls hos t plants are ruse and dogwood . It and only in t race amounts, feeding on was also found feeding on birch , apple. maple, and willow. Though univol­ (g) A l'gyrotaenia dorsa lana (Dyar), tine in the Okanagan Valley it is b:­ was fo und, infrequen tly ( 1% ), on voltine about 300 miles south in apple and rose. The recorded host Washington State. The feeding habits plants are Pinaceae (Powe ll 1964) differ from those described for East­ and (Freeman 195 8 ). ern North America. In the Oka nagan Parasites Valley the larva first feeds OE th e undersurface of a leaf under webbing The following pa rasites were rear­ and later does not roll leaves; u,'Oually ed from leaf-rollers in the Okanagan it is found on leaves not fed upon by Valley. The host species, when iden­ other species of leaf rollers. In the tifiable, are indicatecl by the letters in East (Hall 1929, Gilliatt 1932 ) the parenthesis, which are from the list early instal' larva establish es feedin g­ above. Only eight of th e 38 species si tes in leaves rolled and partly fed (ma rked with a sterisks below) were upon by oth er speCies of leaf rollers. rearcd more tha n five times a nd are Nine species of parasites were reared. th erefore of possible control signifi­ In one locality larvae were found to cance. be infected with a granulosis virus Ich enumoniclae: "'[toplectis quad­ th at killed th em in the final ins tar. licinglllata (Prov.) (a,b,c); H ercus pleuralis (Prov.) (b); Scambus tec­ (d ) Platynota idaeusalis (Walk.), umse h (Harr.) (b); Ex ochus nigripal­ the tufted apple bud , was not pis tectulum Townes (a ) ; Phytodietus common (3% ). Apple and rose are sp. ( b) ; C lypa sp. (c); Acropimpla primary hos t plants and it was also albol'tica (Cress. ) (b) ; Diadegma sp. founcl feeding on willow. I n New York 1 (b,c,cl); Diadegma sp. 2 (a) ; C elis the larva over winters as two different sp. (a ); Pimplinae (b). si zes (Ch apman and Lienk 1971) but Braconiclae : .". Microgaster epago­ only as one in t h e Okanagan Valley. ges Gah an (a,b,c); "' Apanteles cacoe­ One parasite species was reared. ciae (Riley) (a,b,c,g); * Habrobracon (e) ajjlictana (Walk.), xanthonotus (Ashm.) (a) ; Onco- 24 J . F:"["O:lIOI.. Soc ·. BlnT. e Il1.1 · \ II:I.\ 71 (1~74 ) , O("T. 1, 1974

plumes americanlls (Weed) (b); Species of other than Agathis annlllipes (Cress.) (a,b); leaf rollers that were found feeding Agathis sp. (b); Apanteles sp. No. 49 on fOliage of apple were: Epinotia (b). rectiplicana Walsm., Epinotia sp., Trichogrammatidae: Trichogram- Heclia ochroleucana Hbn., and Exart­ 1I2a minlltllm Riley (a,b,). ema pIlnctanum Walsm. (Olethreu­ Chalcididae: Spilochalcis albijrons tinae); Filalima clemissae Kief. and (Walsh) (b); Brachymeria ovata Trachoma walsinghamiella Bu s c k ovata (Say) (b,c) . (Gelechiidae) ; and Lithophane georgii Eulophidae: Euloph us anomocerus Grt. (Noctuidae). (Crawf.) (a); Sympiesis marylanden­ Key To Leaf Rollers sis Gira ul t (b) ; Elachertus aeneoniger Key to final-instal' larvae of six (Girault) (b); Elachertus cacoeciae leaf rollers on apple in the Okanagan (Howard) (b) ; Elachertus poss. n . sp. Valley, B.C. (a ); Diclaclocerus westwoodii W est­ 1. Hody- li ght green. head darker green 2 wood (a); Pediobius s p. near lonch­ Roch· dark green or brownish green. head red­ ({eae Burks (a) . d is h brown. da rk brown. or black :3 Elasmidae: Elasmus atratus How­ :2. Full-g rown at a bout end of apple bloom: relati\·eh· sluggish: usuallv ,carce. ard (a,b). Argyrotaenia dorsalana pteromalidae: Dibrachys caVIlS Full-grown two or th ree weeks after end of (Walk.) (a); Dibrachys poss. n. sp. apple hloom: ,·en · act iq': often freq uent. (b) ; H abrocytus phycidis Ash . (a,b,c) ; Pandemis limitata Catolaccus aeneoviricl is (G ira u I t) :1. H ead brown to bl ack. hod\· dark green: usual­ Ca,b) . h· common ~ Head reddi"h brown to brown. bock brown­ Tachinidae: " N emorilla pyste i;; h to hr(J\\"Ili sh green: usuallv scarce· :) (Wa lk.) (a,b) ; Compsilura concin­ 4. First thoracic leg;; hrown. remainder green: nata (Mg.) (b) ; "H emistm1l2ia tor­ never on pri,·et Archips argyrospilus t ricis (Coq.) (a,b,c); Ewnea caesar All thoracic legs greeni sh: often common on (Ald.) (a,b); 'P seucloperi chaeta erec­ pri ,· et Archip5 rosanus ta (Coq.) (a,b,c). G. Hod,v hr()\vnish. s0111etinles wit h t\V O dark brown "tripe;; : full grown late in summer or Associated Lepidoptera earh· in fall Syndemis afflictana The apple leaf r ollers recorded Rod·\, browni'h-green. n~t with stripes: full­ from the Okanagan Valley by Ven­ grown late in spring or earl\ in summer. Platy nota idaeusalis ables (1924) but not found in the 1972 s ur v e y were Acleris maximana Acknowledgements (Barnes & Busck) and Aphelia allen­ The aut hors thank the following: Dr. H. Mad­ ,en. Ca nada Department of Agriculture Hesearch icma (Fern.) . Stat ion. SUlllmerland. for much ad,·ice and assist­ In the 1972 s urvey three s peCIes of ance throughout this im·estigation: Drs. E. R ock­ leaf rollers were found on primary burne and C. Lewis. for identifyi ng the Lepidop­ tera. and Drs ..J. Barron. M. Ivonochko. \Y . host plants of apple-feeding s pecies Mason. D. \Y ood. and C. Yoshimoto. all of the but not themselves on apple: Acleris Entomology Research Institute. Canada Depart­ jorbesana (McD.) and Acleris .s p . near ment of Agriculture. Ottawa, for identifying bowmana (McD.), on dogwood, and t he parasit e;;. 'rhe work was fin anced bv an operating research grant fr om the :\ationai He­ Croesia albicomana (Clem.), on rose. sea rch Counci l of Canada to R. P . Reirne.

References Chapma n. P ..J. a nd S. E . Lienk. 1971. Tortricid fauna of apple in New '{ork t Lepidoptera: T ort ri cidae). New York Agr. Exp. 8ta .. Gene,·a. Spec. Pub. 1:22 pp. Freeman. T . :\. W,jl"l. The Archipinae of N orrh America (Lepidoptera: Tortricidaei. Can. Entomol. Suppl. 7. 89 pp. J . EYII)\IOL. S' ll" . DIUT. CO L OI"!.\ 7] ( 1074 ) . OCT. 1, 1074 25

(;illiatl. F . C'. 19:1:2. Life hi stor\' a nd ha bi ts of the three-lined lea f roll er. Pande mis limitata Rob .. in :"J()\'a Scotia . Sci. Agr. 12(9): 506-;):21. Hall.·J. A. 19:29. Leaf roll ers a ttack ing the apple in Norfolk County . Ontario. Rep. Entomol. Soc. Ont a rio 60: 1:1,·141. \'l aver. D. F. and H. P. Beirne. 19':1. Aspec ts of the ecologv of a pple leaf rollers (Lep.: T ortric.) in the Okanagan Vallev. Hritish Columbia. Can. Entomol. l 06::3-19 -:3.~:2. Powell. .J. A. 1964. Biological and taxonomic studies on T ortricine , with reference to the species in California. Lni\·. California Pub. Entomol. 32. 317 pp. Vena bles. E. P. 19:24. Leaf-roll ers a ttacking orcha rd trees in the Okanaga n Valley. Proc. Entomol. Soc. Hrit. Columbia 21: :22·26. v\'hitehead. W . E. 19:26. Notes on the curra nt leaf roller (Cacoecia rosana Linn.) in :\ova Scotia. Proc. Acadian Entomol. Soc. 10: 76-79.

INFLUENCE OF STREAM SEDIMENTS ON DISTRIBUTION OF MACROBENTHOSI M. A. BRV3VE).' A).'O K. V. PRATHEH' Depa rtment of Entomol og~ ' l i ni ve r s it~ · of Idaho Moscow. Idaho

ABSTRACT Studi es were conduct ed in the lab o r a t o r ~' and fi eld to determine the subsi rate relationships of five species of st ream represent ing the orders Epherneroptera. Pl ecoptera. Trichoptera and Diptera. Va rious combina tions of pebble and sand were tested in the presence or absence of cobbles. Substrates with cobble were ge nerall y preferred over substra tes without cobble. The pre­ ference for co bble generall y increased as the sediments a round the cobble de­ creased in size. Substrates with unembedded cobble were sli ghtly preferred O\'e r half-e mbedded cobble: completelv embedded cobble in fine sand proved unacceptable to mOS T species. Three t~'pe s of substrate-distribution patterns are recognized: stream insects which inha bit subst rat e surfaces: interstices: and both substra te surfaces and interstices.

Introduction cerned with substrate relationships Sediment pollution is of increasing of insects, but we r ecognize that other concern to stream ecologists. Exces­ trophic le\:,els are also affected by sive accumulations of sediment in sediments . Influence upon anyone mountain streams as a result of agri­ trophic level may cause profound side cultural practices, logging, road con­ effects on other components in the struction, dredge mll1ll1 g, etc. can ecosystem. h a ve serious detrimental effects on This paper attempts to clarify the the stream biota. The role of sedi­ substrate relationships and ecology ments in the distribution and abund­ of five stream insects studied in the ance of stream benthos has been re­ la boratory and field and suggests rea­ portee! by Pervical and Whitehead sons for specific affinities for certain (1929), Cummins (1964, 1966), Scott substrate conditions. (1966) and others . This paper is con-

H l' ~l" , ln h "'lI pp! In (.e! ill p,m lIy t ht' l ·.:--. . I h 'p,l rt 11\1..' 111 "I [ht­ Materials and Methods i Jllt'riof ;1'" ,Hlthnri/l,d lIndt-" tilt· \\ - at l~ r !\t.·'.dl!tl'l ·l·.... - \{'t !I I 1!lIi l. -substrate rela tionships were I'uhlll' I. ~ !\\ ,...... : .:; -;- q. f!lIhl i ... hdl w l lh rill' :I JlprI1\:tl Iii lilt' [) i n','1 111" ( d til(' i (bh'l . \ grinllll1rt· j':"jlt'fltlH:rlt .....:..'at ilOll ; 1" 1-<1· ... ('; 11"1'11 P ;I )1(·f studied in the laboratory in artificial :,\ ", -;-·Hil. streams similar to one described by i 'IT:-l 'll l :Hld rT ...... Third \ ,:--., .-\rrm \ll,dil ', ll 1.:lhllf.t1 l lr\ 1:1 . \kJ!ht'r ... "rl. (; ('"r;:i:1. I :--' .. \ Brusven (1973). Temperature was