FIDS Report 93-6 Forest Insect and Disease Conditions Vancouver Forest Region • 1992 Rod Turnquist and Dennis Clarke Forestry Forêts lel Canada Canada Canada Table of Contents Page VANCOUVER MAINLAND AND VANCOUVER ISLAND FOREWORD 3 INTRODUCTION 4 SUMMARY 4 DOUGLAS-FIR PESTS 7 Western spruce budworm, Choristoneura occidentalis 7 Douglas-fir beetle, Dendroctonus pseudotsugae 10 Douglas-fir tussock moth, Rusty tussock moth, Orgyia pseudotsugata, 0. antiqua badia 12 Laminated root rot, Armillaria root rot, Phellinus weirii, Armillaria ostoyae 13 Abiotic damage 14 PINE PESTS 14 Mountain pine beetle, Dendroctonus ponderosae 14 Pine sawfly, Neodiprion nanalus contortae 15 European pine shoot moth, Rhyacionia buoliana 17 SPRUCE PESTS 17 Spruce beetle, Dendroctonus rufipennis 17 Spruce weevil, Pissodes strobi 17 Spruce aphid, Elatobium abietinum 18 TRUE FIR PESTS 18 Western balsam bark beetle, Dryocoetes confusus 18 Balsam woolly adelgid, Adelges piceae 18 Needle blights, Isthmiella sp., Phaeocryptopus nudus 19 CEDAR PESTS 19 Cedar leaf blight, Didymascella thujina 19 Cedar flagging 19 HEMLOCK PEST 19 Western blackheaded budworm, Acleris gloverana 19 SPECIAL SURVEYS 21 Pinewood nematode, Bursaphelenchus xylophilus 21 Acid rain plots 21 Pests of young stands 23 Seed orchards 23 DECIDUOUS TREE PESTS 26 Gypsy moth, Lymantria dispar 26 Winter moth, Operophtera brumata 26 Cottonwood sawfly, Nematus currani 27 Bigleaf maple scorch and leafspots, Xylella fastidiosa, Rhytisma punctatum, Cristulariella depradens 27 Western winter moth, Erranis tiliaria vancouverensis 28 Dogwood leaf blight, Discula destructiva 28 Birch leafminers, Fenusa pusilla, Profenusa thomsoni 29 Fall webworm, Hyphantria cunea 29 Jumping gall wasp, Neuroterus saltatorius 29 An oak leaf phylloxeran, Phylloxera sp. near glabra 30 NEW RECORDS OF OCCURRENCE AND DISTRIBUTION 30 OTHER NOTEWORTHY AND MINOR PESTS 31 QUEEN CHARLO FIE ISLANDS SUMMARY 33 HEMLOCK PESTS 33 Western blackheaded budworm, Acleris gloverana 33 Hemlock sawfly, Neodiprion tsugae 34 Hemlock dwarf mistletoe, Arceuthobium tsugense 34 SPRUCE PESTS 34 Spruce aphid, Elatobium abietinum 34 Cooley-spruce gall adelgid, Adelges cooleyi 35 Spruce needle blight, Lirula macrospora 35 Large-spored spruce-Labrador tea rust, Chrysomyxa ledicola 35 PESTS OF YOUNG STANDS 35 MINOR PESTS 37 APPENDICES 39 Foreward Forest Insect and Disease Survey (FIDS) is For the Vancouver Island district: a nation-wide network within Forestry Canada with the responsibility of: (1) producing an Forest Insect and Disease Survey overview of forest pest conditions and their Forestry Canada implications including predictions where possi- Kye Bay, R.R.#1 ble; (2) maintaining records and surveys to sup- Comox, B.C. port quarantines; (3) supporting forestry V9N-5N1 Ph. 339-4722 research with field studies, records, Herbarium and Insectary collections; (4) providing advice For the Queen Charlotte Islands: and extension on forest insect and disease con- ditions; (5) developing and testing survey tech- Forest Insect and Disease Survey niques; (6) and conducting related biological Forestry Canada and impact studies, Box #23, Terrace, B.C. During the year, correspondence and V8G-4A2 Ph. 635-7660 inquiries regarding forest pest problems, and requests for publications can be directed to For the Bella Coola/Mid-Coast area: FIDS headquarters at: Forest Insect and Disease Survey Pacific Forestry Centre Forestry Canada Forestry Canada Sidcum sub., Comp. 33, R.R. #3 506 West Burnside Road Williams Lake, B.C. Victoria, B.C. V2G-1 M3 Ph. 392-6067 V8Z-1 M5 Ph. 363-0600 During the field season, May to October, inquiries can be directed to the FIDS field sta- tions. For the Vancouver Mainland district: Forest Insect and Disease Survey Forestry Canada P.O. Box 692 Agassiz, B.C. VOM-1A0 Ph. 796-2042 The Queen Charlotte Islands section, Introduction included seperately in this report, was submitted by the Prince Rupert west FIDS Ranger, John This report outlines the status of forest pest Vallentgoed. The annual survey of the Queen conditions in the Vancouver Forest Region for Charlotte Islands was conducted from July 13 to 1992 and forecasts population trends of some 24. Insect and disease data from the Mid-coast Forest District was collected by Cariboo FIDS potentially damaging pests. Pests are listed by host in order of importance with emphasis given Ranger, Bob Erickson. FIDS insectary biologist, to those capable of sudden damaging out- Robert Duncan contributed to the sections on breaks. Most of the information was gathered the oak leaf phylloxeran and the jumping gall wasp as well as providing information on the through the monitoring of already known or recently reported insect or disease problems; winter moth situation in the Greater Victoria the detection of pest problems through travels area. The FIDS pathologist/mycologist Dr. through the region; annual aerial surveys during Brenda Callan contributed to the bigleaf maple scorch and leafspot section. The author wishes which major pest problems are mapped for area and severity; and several special surveys and to acknowledge the support of the British Columbia Ministry of Forests which assisted collections. with air transportation and Scott Paper Ltd., Special surveys carried out during the field which assisted with ground transportation and season included: inspections of provincial parks, defoliator and disease sampling. ecological reserves, seed orchards and acid rain Defoliation intensities are referred to a num- plots; pheromone trapping of spruce budworm, gypsy moth and Douglas-fir tussock moth; ber of times in the report are defined as follows: Douglas-fir tussock moth egg mass surveys; Trace - evidence of feeding barely poplar pest surveys; young stand surveys; detectable close up European pine shoot moth and pine shoot beetle Light - some branch and/or upper crown surveys at Christmas tree farms and; pinewood defoliation, barely visible from the air nematode surveys at log sort yards. Additionally, Moderate - pronounced discoloration and many enquiries from public and industry were noticeably thin foliage, severe top defoliation investigated with pest identification and, where Severe - top and many branches completely possible, control advice provided. Cooperation was also extended to a graduate student from defoliated, most trees more than 50% defoliated Simon Fraser University doing pheromone trap- ping studies on the western hemlock looper. Summary Special collections made during the field season included woodborers and woodborer infested material, pinewood nematode samples, This summary of pest conditions in the cottonwood sawfly larvae, maple leaf scorch, Vancouver Forest Region in 1992 includes a Douglas-fir tussock moth larvae, spruce weevil summary of weather conditions and lists the infested leaders, and worms. These collections most damaging pests, generally in order of contributed to current and continuing studies at importance by host affected. the Pacific Forestry Centre and other research institutes. The winter of 1991-92 and the 1992 grow- ing season were marked by noticeably warmer The forest pest survey field season extend- than normal temperatures. Mean tempera- ed from early May to late September. One hun- tures at the Vancouver, Victoria, and Port Hardy dred and sixty insect and 140 disease collec- Airports from October 1991 to March 1992 were tions were submitted to the Pacific Forestry warmer than the 30 year (1951-80) average by Centre by FIDS personnel. Figure 1 shows the 21, 21, and 19% respectively. Temperatures at locations where samples were collected and the these locations from April to September 1992, area covered by 11 hours of fixed-wing aircraft (considered to be the growing season) were surveys. warmer than the 30 year average by 8, 7, and VANCOUVER FOREST REGION 0 40 80 km FOREST INSECT AND DISEASE SURVEY Figure 1. Locations where one or more forest insect and disease samples were collected and areas covered by aerial surveys to map bark beetle and defoliator infestations in 1992. 8% respectively. These warmer temperatures Balsam bark beetle killed mature alpine fir probably contributed to the marked increase in over 625 ha, down from 1105 recorded in 1991, defoliator populations and resulting damage mostly in the Fraser TSA. New balsam woolly seen regionally this year. adelgid quarantine zone boundaries have offi- cially been adopted. Also, populations and Western spruce budworm lightly to damaged trees were found for the first time on severely defoliated mostly Douglas-fir over Lasqueti Island. Needle blights were 21 130 ha, an almost fourfold increase from the widespread on amabilis fir near Sayward on 5850 ha recorded in 1991. Defoliation increased Vancouver Island and in watersheds in greater in most previously infested stands in the Vancouver. Birkenhead River area and expanded signifi- cantly up the Lillooet River valley north of Western blackheaded budworm popula- Pemberton. New areas of defoliation were also tions remained at endemic levels following their mapped in the Nahatlatch River valley near collapse last year. Boston Bar. Top-kill of up to 3m was recorded on up to 40% of trees in areas that have suf- Cedar leaf blight infections were similar to fered repeated defoliation. Although the area of those recorded in 1991 while the incidence of Douglas-fir beetle attacks declined to 170 ha cedar flagging increased. from 240 ha recorded in 1991, the number of infestations increased to 210 from 57 in 1991. Pinewood nematode surveys concentrat- Douglas-fir