Forest Health Conditions in Nova Scotia 2011 Annual Report
Compiled by: Gina Penny With data from Forest Health Staff
Forest Protection Division Renewable Resources Branch Nova Scotia Department of Natural Resources PO Box 130 23 Creighton Road Shubenacadie, NS B0N 2H0
Telephone: (902)-758-7226 Fax: (902)-758-3210 http://www.gov.ns.ca/natr/forest/foresthealth/default.asp
Publication Number: Report FOR 2013-002
Forest Health Staff
Tanya Borgal Matthew O’Connor Matthew Campbell Jeff Ogden Jacqui Gordon Jim Rudderham Mike LeBlanc Andrew Young
Editing and Administrative Support
Wanda Dahr John Ross Walter Fanning Suzette Thibodeau
Regional Services Pest detection Officers Eastern Region Central Region Western Region Derek Hart Allan Bland Jamie Brown Michael Hill Mike Kew Brian Comeau Greg Keizer Eric Leighton Bill DesChamp Dolores MacDonald Scott MacEwan William Grover Greg Murphy Matthew McFetridge Kim Huskins Tom Murray Matthew O’Connor Ross Pentz John Ongo Adrian Samson Kevin Totten
Figure 1: Administrative regions of the Nova Scotia Department of Natural Resources.
1 TABLE OF CONTENTS
Acknowledgements…………………………………………………………………………….4
List of Abbreviations and Acronyms Used in This Report…....…………………………….4
Executive Summary………………………………………………………………………….....5
List of Tables………………………………………………………………………………….....8
List of Figures……………………………………………………………………………………9
Introduction……………………………………………………………………………………..11
Status of Forest Pests…………………………………………………………………………11
Insect Pests of Softwoods ...... 11
Eastern Spruce Budworm - Choristoneura fumiferana (Clem.) ...... 11
Pheromone Trap Survey ...... 12
Overwintering Larva (L2) Survey ...... 13
Jack Pine Budworm - Choristoneura pinus pinus (Free.) ...... 14
Pheromone Trap Survey ...... 14
Overwintering Larva (L2) Survey ...... 15
Hemlock Looper - Lambdina fiscellaria fiscellaria (Gn.) ...... 16
Pheromone Trap Survey ...... 16
Overwintering Egg Survey ...... 17
Spruce Beetle - Dendroctonus rufipennis (Kirby) ...... 18
Permanent Monitoring Plots ...... 19
Whitemarked Tussock Moth - Orgyia leucostigma (J.E. Smith) ...... 20
Overwintering Egg Mass Survey ...... 20
Eastern Blackheaded Budworm - Acleris variana (Fernald) ...... 22
Overwintering Egg Survey ...... 22
Balsam Fir Sawfly - Neodiprion abietis (Harr.) ...... 23
2 Overwintering Egg Survey ...... 23
Risk and Predicted Defoliation Maps ...... 24
Balsam Woolly Adelgid - Adelges picea (Ratz.) ...... 26
Overwintering Nymph and Damage Surveys…………………………………………….26
Permanent Monitoring Plots ...... 28
Balsam Twig Aphid – Mindarus abietinus (Koch) ...... 31
Balsam Gall Midge – Paradiplosis tumifex (Gagné) ...... 32
Insect Pests of Hardwoods…………………………………………………………...………33
Gypsy Moth - Lymantria dispar (L.) ...... 33
Pheromone Trap Survey ...... 34
Invasive Pests……………………………………..…………………………………………...38
Brown Spruce Longhorn Beetle - Tetropium fuscum (Fabr.) ...... 38
Pheromone Trap Survey ...... 39
Arthropods of Importance to Human Health……………..…………………………………41
West Nile Virus ...... 41
Tick Survey ...... 41
Pest Identification Service………………………………………………………………. …...42
Communications…………………………………………………………………………. …...42
Newsletter: Insectary Notes ...... 42
Website ...... 43
Extension and Outreach ...... 43
Appendix I – Glossary…………………………………………………………………………44
3
Acknowledgements
To assemble, analyze, and present the support of the PDO’s and their Area information contained within this report Supervisors. requires a great deal of effort from many individuals. Without their efforts to Appreciation is extended to the staff of gather information and data, this report the Canadian Forest Service (CFS) for would not be possible. their cooperation. Their research in Nova Scotia as well as the information Thanks to the Nova Scotia Department and expertise they share relating to of Natural Resources (NSDNR) regional forest pests and forest conditions staff, especially the Pest Detection continues to be a valuable resource. Officers (PDO’s), who are the backbone of many provincial surveys. These Thanks are also given to the Canadian surveys would be impossible without the Food Inspection Agency (CFIA) for their assistance and information exchange during the invasive insect surveys.
List of Abbreviations and Acronyms Used in This Report
CFIA Canadian Food Inspection Agency CFS Canadian Forest Service ha Hectares NSDNR Nova Scotia Department of Natural Resources PDO Pest Detection Officer
4
Executive Summary
This annual report contains information on forest insects and diseases monitored by Forest Health staff and PDO’s for the period up to and including 2011. As well as information concerning our combined efforts to assist in research conducted by the CFS and monitor invasive pests with the CFIA.
Eastern Spruce Budworm (Choristoneura fumiferana): In 2011, 35% of pheromone traps were positive, down from 57% recorded in 2010 which was the highest percentage we’ve seen since 1994. During our 2011 branch survey, 52 points were examined and no overwintering larvae (L2’s) were detected.
Jack Pine Budworm (Choristoneura pinus pinus): Forest Health began using pheromone traps to monitor Jack pine budworm populations in 2006. Since that time the percentage of positive traps has remained above 75% until 2010 when it dropped by almost half to 36%. In 2011, the percentage of positive traps rose to 48%. No overwintering larvae were detected during our branch surveys.
Hemlock Looper (Lambdina fiscellaria fiscellaria): In 1993, a pheromone monitoring system was initiated to detect hemlock looper moths. Percent positive traps increased slightly from 93.9% in 2010 to 94.9% in 2011 while the mean trap catch increased from 19.8 to 70.6. Follow up egg surveys are conducted around pheromone traps with the highest moth catches. In 2011, branch samples were taken from three trees at 46 sites in the Eastern Region. Eggs were detected at 28.3% of sites sampled, up from 10% in 2010 and 0% in 2009.
Spruce Beetle (Dendroctonus rufipennis): Widespread spruce beetle mortality of mature and over-mature white spruce is occurring throughout the province. In 2004, eighteen fixed radius plots were established in red and white spruce stands in central Nova Scotia. When plots were surveyed in 2011, 12.86% of white spruce and 6.38% of red spruce were either infested with or had been killed by spruce beetle. This is down from 2010 when the percent of infested and beetle killed trees were 44.80% and 9.85% for white and red spruce respectively. The percentage of beetle killed white and red spruce trees has also dropped significantly. This can be attributed to the fact that many of the trees previously marked as dead were this year recorded as either missing or not found due to factors such as blow down.
Whitemarked Tussock Moth (Orgyia leucostigma): In 2011, an overwintering egg mass survey was conducted with 343 sites sampled province wide. The percentage of sites where egg masses were detected has risen slightly from 7.7% in 2010 to 10.8% in 2011.
Eastern Blackheaded Budworm (Acleris variana): In 2011, branch samples were taken from three balsam fir trees at 62 sites in the Eastern Region. Eggs were detected at 83.9% of the sites surveyed. This is a slight increase from 74.1% in 2010. Egg
5 numbers still remain low but have increased three fold from the maximum of five found in 2010 to 15.3 in 2011.
Balsam Fir Sawfly (Neodiprion abietis): Our overwintering egg survey for 2011 include 123 sites, 59% of which were positive, up from 51% in 2010 and the highest percentage we’ve seen since 1998.
Balsam Woolly Adelgid (Adelges picea): Since 2000, Forest Health staff has monitored balsam woolly adelgid populations in a general way. This survey is not a predictive survey; it simply quantifies the damage that occurred the previous summer. In 2011, the percentage of sites with overwintering nymphs declined to 5.7%. This is down from 8.7% in 2010. For both 2010 and 2011, gouted branches were found at 1.6% of the sites. In the fall of 2009, 14 permanent monitoring plots were established to measure adelgid damage and overall population changes. In 2011 overwintering was monitored at 11 of the 14 plots. Populations had increased at 1 plot, decreased at 3 and no change was found at the remaining 7 plots. Mortality of overwintering nymphs occurs below -20oC. So the recorded decreases weren’t unexpected due to the cold winter temperatures measured at the plots during 2010-2011.
Balsam Twig Aphid (Mindarus abietinus) and Balsam Gall Midge (Paradiplosis tumifex): Forest Health monitors twig aphid and balsam gall midge populations in a general way by assessing their presence on balsam fir branch samples collected for our balsam fir sawfly survey. This is not a predictive survey; it simply quantifies the damage that occurred the previous summer. In 2011, of the 123 sites surveyed, there were no sites with balsam twig aphid affected shoots and only one site that had balsam gall midge affected shoots.
Gypsy Moth (Lymantria dispar): Pheromone monitoring of the gypsy moth occurs in two parts. Individual multipher traps are deployed at designated sites province wide and delta traps are placed in various towns outside the CFIA regulated zone. In 2011, 68% were positive up from 58% the year before with a total of 3188 moths caught up from 3093 recorded in 2010. This survey provides a snapshot of the population across the province; based on our 2011 survey results trap catches remained fairly stable with changes detected in two counties within the CFIA regulated zone: an increase in Digby County and a decrease in Annapolis County. Based on our delta trap survey the only town that continues to show a population increase is New Glasgow in Pictou County. However, since 2009 the average moth catch per trap has been on the decline. In 2011, this trend has held true with an average moth catch of 9 down from 14 moths per trap in 2010.
Brown Spruce Longhorn Beetle (Tetropium fuscum): The 2011 trapping survey resulted in 20 positive sites outside the beetle containment area. Of these positive sites, five are new for Nova Scotia in the counties of Halifax, Hants, and Luneburg. There was also a positive location in New Brunswick located near a campground in Kouchibouguac National Park. This is the first time the beetle has been detected outside of Nova Scotia. These six new finds brings the total number of positive sites outside of the beetle containment area to 65. Additional pheromone traps were also deployed
6 throughout Atlantic Canada in Prince Edward Island, New Brunswick and Newfoundland and Labradour. All, with the exception of the one positive in New Brunswick, were negative for brown spruce longhorn beetle
West Nile Virus: There have been no human cases of West Nile virus acquired in Nova Scotia. Mosquito surveillance has been suspended due to lack of West Nile virus activity, but will be re-introduced if the virus is again detected within wild bird populations. As of 2010, dead birds in Nova Scotia are no longer tested for West Nile virus. No birds have tested positive since 2003.
Tick Survey: Forest Health has been conducting tick surveys since 2002 with the lead agencies being the Nova Scotia Department of Health and Wellness and the Public Health Agency of Canada. In 2011, 1500 ticks were submitted to Forest Health for identification, the majority, 850 were black legged ticks (Ixodes scapularis). Currently, there are five established populations of Blacklegged ticks in Nova Scotia: Pictou County - areas around Melmerby Beach, Egerton, Kings Head, and Pine Tree; Lunenburg County - (Blue Rocks, Garden Lots, Heckmans Island, First Peninsula as well as the areas immediately surrounding them; Halifax County - Admirals Cove in Bedford; Shelburne Count - Gunning Cove and; Yarmouth County: Gavelton area.
Pest Identification Service: Since 1995, Forest Health staff has coordinated the identification of pests affecting Nova Scotia’s forests. In 2011, 101 inquiries were answered. Of these inquiries, 25 (24.8%) dealt directly with our forest resource i.e. plantations and woodlots; the remaining 76 (75.3%) were general homeowner inquiries.
7 List of Tables
Table 1: Summary of eastern spruce budworm (Choristoneura fumiferana) pheromone trap surveys conducted by Forest Health in Nova Scotia from 1990 to 2011.
Table 2: Summary of jack pine budworm (Choristoneura pinus pinus) pheromone trap surveys conducted by Forest Health in Nova Scotia from 2006 to 2011.
Table 3: Summary of jack pine budworm (Choristoneura pinus pinus) overwintering larva (L2) surveys conducted by Forest Health in Nova Scotia from 2006 to 2011.
Table 4: Summary of hemlock looper (Lambdina fiscellaria fiscellaria) pheromone trap surveys conducted by Forest Health in Nova Scotia from 1993 to 2011.
Table 5: Summary of hemlock looper (Lambdina fiscellaria fiscellaria) overwintering egg surveys conducted by Forest Health in Nova Scotia from 1992 to 2011.
Table 6: Summary of spruce beetle (Dendroctonus rufipennis) permanent plot surveys conducted by Forest Health in Nova Scotia from 2004 to 2011.
Table 7: Summary of whitemarked tussock moth (Orgyia leucostigma) overwintering egg surveys conducted by Forest Health in Nova Scotia from 1999 to 2011.
Table 8: Summary of eastern blackheaded budworm (Acleris variana) overwintering egg surveys conducted by Forest Health in Nova Scotia from 2004 to 2011.
Table 9: Summary of balsam fir sawfly (Neodiprion abietis) overwintering egg surveys conducted by Forest Health in Nova Scotia from 1998 to 2011.
Table 10: Summary of balsam woolly adelgid (Adelges picea) overwintering nymph surveys conducted by Forest Health in Nova Scotia from 2000 to 2011.
Table 11: Summary of balsam woolly adelgid (Adelges picea) damage surveys conducted by Forest Health in Nova Scotia from 2000 to 2011.
Table 12: Summary of balsam woolly adelgid (Adelges picea) permanent monitoring plot surveys conducted by Forest Health from 2010 to 2011.
Table 13: Summary of balsam twig aphid (Mindarus abietinus) surveys conducted by Forest Health in Nova Scotia from 2003 to 2011.
Table 14: Summary of balsam gall midge (Paradiplosis tumifex) damage surveys conducted by Forest Health in Nova Scotia from 2003 to 2011.
Table 15: Summary of gypsy moth (Lymantria dispar) permanent, multipher pheromone trap surveys conducted by Forest Health in Nova Scotia 1998 to 2011.
8 Table 16: Summary of gypsy moth (Lymantria dispar) delta pheromone trap surveys conducted by Forest Health in Nova Scotia 2000 to 2011.
Table 17: Number of tick identification inquiries from 2002 to 2011.
Table 18: Summary of pest identification inquiries to Forest Health from 2001 to 2011.
List of Figures
Map Disclaimer: The information on these maps may have come from a variety of government and non-government sources. The Department of Natural Resources accepts no liability for any errors, deficiencies or faults on these maps. These maps should not be used for legal purposes.
Figure 1: Administrative regions of the Nova Scotia Department of Natural Resources.
Figure 2: Results of the 2011 eastern spruce budworm (Choristoneura fumiferana) pheromone trap survey.
Figure 3: Results of the 2011 eastern spruce budworm (Choristoneura fumiferana) overwintering larva (L2) survey.
Figure 4: Results of the 2011 Jack pine budworm (Choristoneura pinus pinus) pheromone traps survey.
Figure 5: Results of the 2011Jack pine budworm (Choristoneura pinus pinus) overwintering larva (L2) survey.
Figure 6: Results of the 2011 hemlock looper (Lambdina fiscellaria fiscellaria) pheromone trap survey.
Figure 7: Results of the 2011 hemlock looper (Lambdina fiscellaria fiscellaria) overwintering egg survey.
Figure 8: Location of permanent spruce beetle (Dendroctonus rufipennis) research plots in Nova Scotia.
Figure 9: Results of the 2011 whitemarked tussock moth (Orgyia leucostigma) overwintering egg mass survey.
Figure 10: Results of the 2011 eastern blackheaded budworm (Acleris variana) overwintering egg survey.
Figure 11: Results of the 2011 balsam fir sawfly (Neodiprion abietis) overwintering egg survey.
9 Figure 12: Results of the 2011 balsam fir sawfly (Neodiprion abietis) overwintering egg survey - Eastern Region.
Figure 13: Forest stands at risk for balsam fir sawfly (Neodiprion abietis) 2012 season.
Figure 14: Gross area within which defoliation by balsam fir sawfly (Neodiprion abietis) is forecast to occur in Eastern Nova Scotia in 2012 based on interpolated values from the 2011 fall egg survey.
Figure 15: Results of the 2011balsam woolly adelgid (Adelges picea) overwintering nymph survey.
Figure 16: Results of the 2011 balsam woolly adelgid (Adelges picea) damage survey.
Figure 17: Locations of Forest Health balsam woolly adelgid (Adelges picea) permanent monitoring plots.
Figure 18: Results of 2011 population monitoring at balsam woolly adelgid (Adelges picea) permanent monitoring plots.
Figure 19: Minimum temperatures (oC) recorded at balsam woolly adelgid (Adelges picea) permanent monitoring plots from November 2010 to April 2011.
Figure 20: Results of the 2011 balsam twig aphid (Mindarus abietinus) damage survey.
Figure 21: Results of the 2011 balsam gall midge (Paradiplosis tumifex) damage survey.
Figure 22: Results of the 2011 gypsy moth (Lymantria dispar) permanent trap survey.
Figure 23: Results of the 2011 gypsy moth (Lymantria dispar) delta trap town survey.
Figure 24: Brown spruce longhorn beetle (Tetropium fuscum) containment area 2011.
Figure 25: Positive sites (20) detected outside of the brown spruce longhorn beetle (Tetropium fuscum) containment area in 2011.
Figure 26: New (circled) brown spruce longhorn beetle (Tetropium fuscum) positive sites detected outside of the containment area in 2011.
Figure 27: Brown spruce longhorn beetle (Tetropium fuscum) trap locations for eastern Canada in 2011.
10 Introduction
Forest Health is part of the Forest surveys, Forest Health staff, with the Protection Division in the NSDNR. Our assistance of PDO’s, record forest mission is to provide accurate health occurrences province-wide. information on the health of Nova Scotia's forests and provide information Forest Health staff survey and monitor and management options to forest numerous insect pests that affect Nova stakeholders. Scotia’s forests and impact Christmas tree health. The protection of these The main responsibilities of the Forest valuable resources depends on early Health group are to: detection and assessment of problems • Monitor forest pests and develop so that action can be taken quickly and better detection methods. effectively. • Analyze forest health conditions using field and survey data. Forest Health also assists the Canadian • Provide accurate information and Food Inspection Agency and the education to forest stakeholders in a Canadian Forest Service to detect the timely manner. presence of invasive alien insects. We • Develop and maintain management also provide technical assistance to the options and systems. Nova Scotia Department of Health and Public Health Agency of Canada to Through a systematic monitoring monitor the populations of arthropods of program including ground and aerial importance to human health.
Status of Forest Pests
Insect Pests of Softwoods
Eastern Spruce Budworm - Choristoneura fumiferana (Clem.) The native spruce budworm is widely collapsing in 1987. Since that time distributed throughout Canada. It has population levels have decreased caused more damage to Nova Scotian dramatically. softwood forests than any other insect. Over-mature balsam fir is the preferred Forest Health staff monitor eastern host but white, red, and black spruce spruce budworm populations using a may also be attacked. The last major combination of pheromone traps to eastern spruce budworm outbreak in capture adult male moths and branch Atlantic Canada occurred in the 1970’s, samples to collect overwintering second peaking in Nova Scotia in the early 80’s, instar (L2) larvae.
11
Pheromone Trap Survey In 2011 Forest Health staff monitored with the exception of 2010, the average 150 pheromone traps province wide of number of moths caught has which 35% were positive (Figure 2). consistently remained below one moth This is down from 57% recorded in 2010 per trap. This year the average moth which was the highest percentage we’ve catch rose to one moth per trap. seen since 1994 (Table 1). Since 1997,
Figure 2: Results of the 2011 eastern spruce budworm (Choristoneura fumiferana) pheromone trap survey.
Table 1: Summary of eastern spruce budworm (Choristoneura fumiferana) pheromone trap surveys conducted by Forest Health in Nova Scotia from 1990 to 2011.
Number Number (%) Number of Moths/Trap Trap Mean Year of of Positive Low Moderate High Catch Trap Zero Traps Traps 1-50 51-100 >101 Range Catch 1990 13 13 (100) 0 12 1 0 11 – 76 33.3 1991 17 15 (88.2) 2 13 2 0 0 – 59 28.2 1992 25 24 (96.0) 1 19 3 2 0 – 132 34.4 1993 18 17 (94.4) 1 13 0 4 0 – 300 55.6 1994 21 15 (71.4) 6 15 0 0 0 – 31 6.6
12 Number Number (%) Number of Moths/Trap Trap Mean Year of of Positive Low Moderate High Catch Trap Zero Traps Traps 1-50 51-100 >101 Range Catch 1995 60 0 (0) 60 0 0 0 0 0 1996 128 0 (0) 128 0 0 0 0 0 1997 119 10 (8.4) 109 10 0 0 0 – 23 0.4 1998 129 6 (4.7) 123 6 0 0 0 – 10 0.2 1999 135 1 (0.7) 134 1 0 0 0 – 1 0.01 2000 64 2 (3.1) 62 2 0 0 0 – 3 0.06 2002 145 5 (3.4) 140 5 0 0 0 – 23 0.2 2003 144 18 (12.5) 126 18 0 0 0 – 4 0.2 2004 150 11 (7.3) 139 11 0 0 0 – 38 0.4 2005 151 33 (21.9) 118 33 0 0 0 – 21 0.6 2006 150 26 (17.3) 124 26 0 0 0 – 5 0.3 2007 150 59 (39.3) 91 59 0 0 0 – 11 0.8 2008 150 14 (9.3) 136 14 0 0 0 – 8 0.2 2009 141 40 (28.4) 101 40 0 0 0 – 12 0.6 2010 148 85 (57.4) 63 85 0 0 0 – 33 2.6 2011 150 53 (35.3) 97 53 0 0 0 – 16 1.0
Overwintering Larva (L2) Survey During our 2011 branch survey, 52 (Figure 3). No L2’s have been found points were examined and no since 1994. overwintering larvae were detected
Figure 3: Results of the 2011 eastern spruce budworm (Choristoneura fumiferana) overwintering larva (L2) survey.
13 Jack Pine Budworm - Choristoneura pinus pinus (Free.) Jack pine budworm, a native needle mature white pines while red pines, feeding caterpillar, is a close relative of located in outbreak areas, remain the spruce budworm. It was not until relatively untouched. Defoliation of 1953 that it was recognized as a mature white pine by Jack pine separate species. It is found throughout budworm was first detected in the the range of its principal host jack pine. Western Region in 2005. Forest Health Other conifers such as eastern white, staff monitor jack pine budworm red and Scots pines can be attacked populations using pheromone traps and particularly when growing in association overwintering second instar (L2) larval with jack pine. In Nova Scotia, jack pine surveys. budworm defoliation is occurring in
Pheromone Trap Survey Forest Health began using pheromone percentage of positive traps rose to traps to monitor this emerging 48%. The average number of moths per population in 2006 (Figure 4). Since trap has increased almost three fold that time the percentage of positive from 2010 but at 1.3 moths per trap it‘s traps has remained above 75% until still well below the high of eight recorded 2010 when it dropped by almost half to in 2006. 36% (Table 2). This year, the
Figure 4: Results of the 2011 Jack pine budworm (Choristoneura pinus pinus)
pheromone traps survey.
14 Table 2: Summary of jack pine budworm (Choristoneura pinus pinus) pheromone trap surveys conducted by Forest Health in Nova Scotia from 2006 to 2011.
Number Number of Traps Number of Moths/Trap Trap Mean (%) of Year Catch Trap Positive Placed Returned 0 1-10 11-20 21-40 >40 Range Catch Traps 2006 49 45 40 (88.9) 5 29 7 3 1 0 - 48 7.9 2007 70 55 42 (76.4) 13 26 16 0 0 0 - 18 6.9 2008 102 83 66 (79.5) 17 60 3 3 0 0 - 33 4.2 2009 58 58 46 (79.3) 12 45 1 0 0 0 - 14 2.8 2010 50 44 16 (36.4) 28 16 0 0 0 0 - 5 0.5 2011 30 25 12 (48.0) 13 11 1 0 0 0 - 11 1.3
Overwintering Larva (L2) Survey Currently, the majority of published jack In 2006, Forest Health staff began pine budworm biological and survey surveying for overwintering second information pertains to jack pine with instar larvae (L2), reported as L2/m2 of little similar information available for bark (Table 3). At each survey site a white pine. For this reason, we have single mid-crown branch is sampled been working towards developing a from each of three representative predictive survey methodology to mature white pines. No overwintering determine the potential impact of jack larvae were detected during our branch pine budworm on Nova Scotia’s forests. surveys.
Figure 5: Results of the 2011 Jack pine budworm (Choristoneura pinus pinus) overwintering larva (L2) survey.
15 Table 3: Summary of Jack pine budworm (Choristoneura pinus pinus) overwintering larva (L2) surveys conducted by Forest Health in Nova Scotia from 2006 to 2011.
Number 2 Number of L2/m of Bark Range Mean Number (%) of 2 2 Year L2/m L2/m of Sites Positive 0 1-50 51-200 201-500 >500 of Bark of Bark Sites 2006 38 17 (44.7) 21 16 1 0 0 0 - 166 9.9 2007 72 29 (40.3) 43 24 1 4 0 0 - 343 20.4 2008 125 40 (32.0) 85 34 3 1 2 0 - 3256 46.6 2009 85 19 (22.4) 66 19 0 0 0 0 - 44.2 3.0 2010 15 0 (0) 15 0 0 0 0 0 0 2011 5 0 (0) 5 0 0 0 0 0 0
Hemlock Looper - Lambdina fiscellaria fiscellaria (Gn.) Hemlock looper is a native insect whose with the spruce budworm. Since 1961 larvae feed on the needles of various this looper has defoliated approximately tree species including hemlock, spruces, 135,000 hectares. Control programs pine and hardwoods. In Nova Scotia its were conducted in portions of Victoria favorite host is mature to over-mature and Inverness counties 1996 and 1997. balsam fir. To monitor hemlock looper populations, Forest Health staff use pheromone traps Hemlock looper has appeared in Nova and an overwintering egg survey. Scotia in the past usually associated
Pheromone Trap Survey In 1993, a pheromone monitoring remained low. Percent positive traps system was initiated to detect hemlock increased slightly from 93.9% in 2010 to looper moths with PDO’s and Forest 94.9% in 2011 while the mean trap Health staff deploying pheromone traps catch increased from 19.8 to 70.6 at numerous sites province wide. Since (Figure 6, Table 4). 1997, hemlock looper numbers have
16 Figure 6: Results of the 2011 hemlock looper (Lambdina fiscellaria fiscellaria) pheromone trap survey.
Table 4: Summary of hemlock looper (Lambdina fiscellaria fiscellaria) pheromone trap surveys conducted by Forest Health in Nova Scotia from 1993 to 2011.
Number Number of Moths/Trap Trap Mean Number (%) of Year Catch Trap of Traps Positive Low Moderate High Zero Range Catch Traps 1 – 199 200 - 499 >500 1993 18 18 (100) 0 15 3 0 12 - 477 113.9 1994 31 31 (100) 0 15 7 9 1 - 2200 453.3 1995 87 87 (100) 0 42 11 34 8 - 4253 999.3 1996 151 148 (98.0) 3 108 21 19 0 - 3893 235.9 1997 147 145 (98.6) 2 115 25 5 0 - 995 148.0 1998 137 132 (96.4) 5 132 0 0 0 - 165 26.4 1999 144 94 (65.3) 50 94 0 0 0 - 95 4.8 2001 96 76 (79.2) 20 76 0 0 0 - 108 14.7 2002 139 116 (84.5) 23 116 0 0 0 - 107 13.9 2003 136 124 (91.2) 12 116 5 3 0 - 865 53.5 2005 85 80 (94.1) 5 74 5 1 0 - 503 54.8 2006 136 116 (85.3) 20 116 0 0 0 - 100 14.6 2007 143 138 (96.5) 5 138 0 0 0 - 111 24.8 2008 150 140 (93.3) 10 138 2 0 0- 395 26.0 2009 146 123 (84.2) 23 123 0 0 0 - 168 20.2 2010 148 139 (93.9) 9 138 1 0 0 - 286 19.8 2011 136 129 (94.9) 7 115 13 1 0 - 682 70.6 * No traps were deployed in 2000 and 2004. Overwintering Egg Survey Follow up egg surveys are conducted long, were taken from three trees per around pheromone traps with the site. Eggs were detected at 28.3% of highest moth catches. At 46 sites in the sites sampled, up from 10% in 2010 and Eastern Region, branch samples, 45 cm 0% in 2009 (Figure 7, Table 5).
Figure 7: Results of the 2011 hemlock looper (Lambdina fiscellaria fiscellaria) overwintering egg survey. 17 Table 5: Summary of hemlock looper (Lambdina fiscellaria fiscellaria) overwintering egg surveys conducted by Forest Health in Nova Scotia from 1992 to 2011.
Number Fertile Eggs/Branch Mean Eggs/Branch Number (%) of Year Low Moderate High Non of Sites Positive Zero Fertile Parasitized Sites 1 - 9 10 - 19 >20 Fertile 1992 43 13 (30.2) 30 13 0 0 0.14 0 0.02 1993 21 9 (42.9) 12 9 0 0 0.15 0 0 1994 266 194 (72.9) 72 180 14 0 1.97 0.03 0.01 1995 218 192 (88.1) 26 138 21 33 7.93 0.24 0.02 1996 399 299 (74.9) 100 275 17 7 2.26 0.07 0.08 1997 315 172 (54.6) 143 170 1 1 0.64 0.04 0.02 1998 302 39 (12.9) 263 39 0 0 0.06 0 0 1999 25 7 (28.0) 18 7 0 0 0.36 0.01 0.02 2001 91 18 (19.8) 73 18 0 0 0.08 0.03 0.08 2002 142 29 (20.4) 113 29 0 0 0.15 NA NA 2003 38 7 (18.4) 31 7 0 0 0.06 0 0 2004 125 62 (49.6) 54 62 0 0 2.13 0.03 0.01 2005 137 95 (69.3) 42 94 1 0 0.87 0.08 0.59 2006 172 31 (18.0) 141 30 1 0 0.22 0.06 0.37 2007 36 2 (5.6) 34 2 0 0 0.02 0 0 2008 41 4 (9.8) 37 4 0 0 0.03 0 0.01 2009 41 0 (0) 41 0 0 0 0 0 0.1 2010 40 4 (10.0) 36 4 0 0 0.04 0 0.44 2011 46 13 (28.3) 33 13 0 0 0.1 0.04 0.1
Spruce Beetle - Dendroctonus rufipennis (Kirby) The native spruce beetle is the most tremendous build up in spruce beetle significant mortality agent of mature populations due to two main factors the spruce in Nova Scotia. Its preferred host presence of large amounts of is mature to over-mature white spruce susceptible host material and recent but all spruce species can be attacked. mild winters enhancing the survival of Small populations of beetles are always beetle offspring. present in spruce forests, surviving in severely stressed or recently killed trees Forest Health is studying spruce beetle and slash. populations and tree mortality throughout the Central Region using In Nova Scotia, spruce beetle activity permanent research plots. has been both chronic and widespread. We’re seeing mortality of mature and over-mature white spruce throughout the province. There has been a
18 Permanent Research Plots In 2004, eighteen fixed radius plots activity, attack levels and mortality, ( 15m) were established in red and throughout the Central Region. white spruce stands in central Nova Scotia (Figure 8). This project was When plots were surveyed in 2011, conducted in cooperation between the 12.86% of white spruce and 6.38% of NSDNR and the CFS and was partially red spruce were either infested with or funded by the Nova Forest Alliance. had been killed by spruce beetle (Table 6). This is down from 2010 when the These plots were originally established percent of infested and beetle killed to examine the impact of spruce blow- trees were 44.80% and 9.85% for white down, due to hurricane Juan, on the and red spruce respectively. The development of the spruce beetle percentage of beetle killed white and red population and damage levels. After spruce trees has also dropped four years of assessment, spruce beetle significantly. This can be attributed to mortality appeared to be unrelated to the fact that many of the trees hurricane blow-down and was previously marked as dead were this determined to be the result of other year recorded as either missing or not factors. However, plot data is providing found due to factors such as blow down. a useful indication of spruce beetle These plots are reaching the end of their lives and usefulness.
Figure 8: Location of permanent spruce beetle (Dendroctonus rufipennis) research plots in Nova Scotia.
19 Table 6: Summary of spruce beetle (Dendroctonus rufipennis) permanent plot surveys conducted by Forest Health in Nova Scotia from 2004 to 2011. Number (%) of Number of Number (%) of Number (%) of Number (%) of Number (%) of Trees Dead Trees Spruce Beetle Spruce Beetle Trees Not Year Healthy Trees Due to Other Assessed Infested Trees Killed Trees Found Causes Sr Sw Sr Sw Sr Sw Sr Sw Sr Sw Sr Sw 416 347 0 4 0 0 6 2 1 1 2004 423 354 (98.35) (98.02) (0) (1.13) (0) (0) (1.42) (0.56) (0.24) (0.28) 389 295 0 28 0 6 13 10 0 0 2005 402 339 (96.77) (87.02) (0) (8.26) (0) (1.77) (3.23) (2.95) (0) (0) 369 251 6 47 1 20 28 19 1 0 2006 405 337 (91.11) (74.48) (1.48) (13.95) (0.25) (5.93) (6.91) (5.64) (0.25) (0) 342 218 9 42 7 50 33 24 13 3 2007 404 337 (84.65) (64.69) (2.23) (12.46) (1.73) (14.84) (8.17) (7.12) (3.22) (0.89) 327 133 6 36 11 60 29 15 30 21 2008 403 265 (81.14) (50.19) (1.49) (13.58) (2.73) (22.64) (7.20) (5.66) (7.44) (7.92) 323 184 2 23 13 81 39 25 31 24 2009 408 337 (79.17) (54.60) (0.49) (6.82) (3.19) (24.04) (9.56) (7.42) (7.60) (7.12) 282 105 22 31 18 81 49 18 35 15 2010 406 250 (69.46) (42.00) (5.42) (12.40) (4.43) (32.40) (12.07) (7.20) (8.62) (6.00) 266 50 16 8 7 1 39 7 32 4 2011 360 70 (73.89) (71.43) (4.44) (11.43) (1.94) (1.43) (10.83) (10.0) (8.84) (5.71) Sr Sw = red spruce = white spruce
Whitemarked Tussock Moth - Orgyia leucostigma (J.E. Smith) The whitemarked tussock moth occurs balsam fir, may result from the feeding naturally throughout North America. The of high larval populations. With good first recorded outbreak in the Maritimes weather and mild winters, a small occurred in 1937. Since then, localized population can reach high levels within outbreaks have been recorded almost one to two years. Forest Health every year. monitors whitemarked tussock moth populations using an overwintering egg Larvae feed on most hardwood and mass survey. many softwood species. Tree deformation and mortality, especially in
Overwintering Egg Mass Survey An overwintering egg mass survey was 7). The percentage of sites where egg conducted in 2011 with 343 sites masses were detected has risen slightly sampled province wide (Figure 9, Table from 7.8% in 2010 to 10.8% in 2011.
20
Figure 9: Results of the 2011 whitemarked tussock moth (Orgyia leucostigma) overwintering egg mass survey.
Table 7: Summary of whitemarked tussock moth (Orgyia leucostigma) overwintering egg surveys conducted by Forest Health in Nova Scotia from 1999 to 2011.
Number (%) Egg Masses per Three Branch Sample Number Egg of Sites Year of Sites Low Moderate High Mass with Egg Sampled Zero Range Masses 0.01-0.7 0.71-1.99 >2 1999 907 89 (9.8) 818 78 8 3 0 - 5.8 2000 631 90 (14.3) 541 77 6 7 0 - 20.5 2002 633 24 (3.8) 609 20 2 2 0 - 2.3 2003 660 8 (1.2) 652 5 0 3 0 - 4.3 2004 679 33 (4.9) 646 27 3 3 0 - 4.0 2005 662 91 (13.8) 571 89 2 0 0 - 0.8 2006 683 150 (22.0) 533 130 18 2 0 - 5.0 2007 286 44 (15.4) 242 44 0 0 0 - 0.6 2008 290 40 (13.8) 250 40 0 0 0 - 0.4 2009 344 26 (7.6) 318 26 0 0 0 - 0.4 2010 296 23 (7.8) 273 23 0 0 0 - 0.3 2011 343 37 (10.8) 306 37 0 0 0 - 0.5
21 Eastern Blackheaded Budworm - Acleris variana (Fernald) Eastern blackheaded budworm is a 1929. From 1945 to 1950, a series of small, native moth that looks very similar outbreaks swept through the Maritimes. to the spruce budworm. It is found Since then, there have been localized across Canada and feeds on 20 outbreaks in Nova Scotia occurring different conifer tree species. every 10 to 15 years, usually in maturing stands, with a high balsam fir content. Before the late 1920’s, outbreaks in the Maritimes were thought to have been Forest Health monitors eastern caused by the spruce budworm. The blackheaded budworm populations first outbreak that was positively using an overwintering egg mass attributed to the eastern blackheaded survey. budworm in Nova Scotia occurred in
Overwintering Egg Survey In 2011, a single branch was sampled increase from 74.1% in 2010. Egg from three balsam fir trees at each of 62 numbers still remain low but have sites in the Eastern Region (Figure 10, increased three fold from the maximum Table 8). Eggs were detected at 83.9% of five found in 2010 to 15.3 in 2011 of the sites surveyed. This is a slight (Table 8).
Figure 10: Results of the 2011 eastern blackheaded budworm (Acleris variana) overwintering egg survey.
22 Table 8: Summary of eastern blackheaded budworm (Acleris variana) overwintering egg surveys conducted by Forest Health in Nova Scotia from 2004 to 2011.
Number Number of Eggs per 45cm Branch Number (%) of Eggs/Branch Year Low Moderate High of Sites Positive Zero Range Sites 1 - 26 27 - 59 >60 2004 125 125 (100) 0 85 18 22 0.3 - 510.0 2005 202 158 (78.2) 44 156 2 0 0 – 51.3 2006 184 60 (32.6) 124 60 0 0 0 - 8.7 2007 64 10 (15.6) 54 10 0 0 0 - 1.0 2008 64 8 (12.5) 56 8 0 0 0 - 1.7 2009 55 3 (5.5) 52 3 0 0 0 - 5.0 2010 58 43 (74.1) 15 43 0 0 0 - 5.0 2011 62 52 (83.9) 10 52 0 0 0 - 15.3
Balsam Fir Sawfly - Neodiprion abietis (Harr.) The balsam fir sawfly is a native insect The principal host is balsam fir but it can that is found throughout Nova Scotia. It also be found on white, black, and red was first recorded in North America in spruce. Damage is caused by the larvae 1910 and recorded outbreaks in Nova feeding on mature needles. Forest Scotia date back to 1942. Outbreaks Health monitors balsam fir sawfly tend to last three to four years with a populations using overwintering egg varying number of years in between. surveys.
Overwintering Egg Survey Our overwintering egg survey for 2011 highest percentage we’ve seen since include 123 sites, 59% of which were 1998 (Figures 11 and 12, Table 9). positive, up from 51% in 2010 and the
23 Figure 11: Results of the 2011 balsam fir sawfly (Neodiprion abietis) overwintering egg survey.
Figure 12: Neodiprion abietis Results of the 2011 balsam fir sawfly ( )
overwintering egg survey - Eastern Region.
Table 9: Summary of balsam fir sawfly (Neodiprion abietis) overwintering egg surveys conducted by Forest Health in Nova Scotia from 1998 to 2011.
Number Egg Niches/Branch Egg Number (%) of Year Niches of Sites Positive Low Moderate High Zero Range Sites 1 – 12.6 12.7 - 24.6 >24.7 1998 308 245 (79.5) 20 125 47 116 0 - 610.0 1999 902 476 (52.8) 426 373 46 57 0 - 385.2 2000 624 242 (38.8) 382 200 27 15 0 - 134.9 2001 699 279 (39.9) 420 269 7 3 0 - 56.5 2002 633 269 (42.5) 364 251 12 6 0 - 52.2 2003 659 209 (31.7) 450 207 1 1 0 - 164 2004 669 127 (19.0) 543 123 3 1 0 - 59 2005 411 130 (31.6) 281 128 1 1 0 - 121 2006 430 8 (1.9) 422 7 1 0 0 - 19 2007 35 6 (17.1) 29 6 0 0 0 - 3 2008 42 8 (25) 26 7 0 1 0 - 55 2009 46 3 (6.5) 43 0 1 2 0 - 192 2010 127 65 (51.2) 62 33 5 27 0 - 1049 2011 123 72 (58.5) 51 32 11 29 0 - 315.5
Risk and Predicted Defoliation Maps Our 2011 egg surveys detected high resource and to identify monitoring numbers of overwintering balsam fir priorities, the Risk Services Unit sawfly eggs. To quantify the potential conducted an analysis to identify those impact of this pest to the local forest forested stands capable of supporting
24 serious balsam fir sawfly infestations survey data was also analyzed and and ranked these stands relative to their interpolated to forecast the possible proximity to known balsam fir sawfly egg extent of balsam fir sawfly defoliation for survey points (Figure 13). Our fall egg the 2012 season (Figure 14).
Figure 13: Forest stands at risk for balsam fir sawfly (Neodiprion abietis) 2012 season.
25 Figure 14: Gross area within which defoliation by balsam fir sawfly (Neodiprion abietis) is forecast to occur in Eastern Nova Scotia in 2012 based on interpolated values from the 2011 fall egg survey. Balsam Woolly Adelgid - Adelges picea (Ratz.) The balsam woolly adelgid is native to As they feed, the adelgids inject saliva Central Europe and was accidentally into the tree causing swellings, also introduced to Nova Scotia in 1910. called gout, on branches and twigs. Feeding exclusively on true firs, genus: Their feeding also causes stunted Abies, it is considered a serious pest of terminal growth, top kill, and the forest, Christmas, landscape, and seed formation of compression wood. This trees. red compression wood can not carry water or nutrients so eventually the tree will loose its needles and die.
Overwintering Nymph and Damage Surveys Since 2000, Forest Health staff has simply quantifies the damage that monitored balsam woolly adelgid occurred the previous summer. In 2011, populations in a general way. All branch the percentage of sites with samples from our balsam fir sawfly overwintering nymphs declined to 5.7%. survey are visually inspected for balsam This is down from 8.7% in 2010. The woolly adelgid damage (a.k.a. gouting) percentage of sites with gouted (Table 11, Figure 16) as well as dormant branches also declined from 1.6% in nymphs in buds (Figure 15, Table 10). 2010 to 0.81% in 2011. This survey is not a predictive survey; it
Table 10: Summary of balsam woolly adelgid (Adelges picea) overwintering nymph surveys conducted by Forest Health in Nova Scotia from 2000 to 2011.
Number of Sites with Number Number Overwintering Nymphs (%) of Year of Sites (3 buds/branch/site) Positive Sampled Low Moderate High Sites Zero 1 - 3 4 - 7 >8 2000 624 353 (32.0) 271 341 10 2 2001 699 356 (50.9) 343 345 10 1 2002 633 321 (50.7) 312 288 26 7 2003 659 255 (38.6) 404 246 7 2 2008 42 3 (7.1) 39 1 2 0 2010 127 11 (8.7) 116 10 1 0 2011 123 7 (5.7) 116 7 0 0 * No surveys were conducted from 2004 - 2007 and 2009.
26
Figure 15: Results of the 2011 balsam woolly adelgid (Adelges picea) overwintering nymph survey.
Table 11: Summary of balsam woolly adelgid (Adelges picea) damage surveys conducted by Forest Health in Nova Scotia from 2000 to 2011.
Number Number of Sites with Gouted Number (%) of Branches Year of Sites Positive Light Moderate High Sampled Zero Sites 1-33% 34-66% >67% 2000 624 346 (55.4) 278 261 57 28 2001 699 264 (37.8) 435 184 61 19 2002 633 249 (39.3) 384 160 72 17 2003 659 236 (35.8) 423 170 47 19 2004 669 171 (25.6) 498 134 32 5 2005 411 102 (24.8) 309 87 15 0 2006 427 71 (16.6) 356 54 15 2 2008 42 5 (11.9) 37 4 1 0 2009 46 10 (21.7) 36 10 0 0 2010 127 2 (1.6) 125 2 0 0 2011 123 1 (0.81) 122 1 0 0
27
Figure 16: Results of the 2011 balsam woolly adelgid (Adelges picea) damage survey.
Permanent Monitoring Plots In the fall of 2009 Forest Health In 2011, overwintering was monitored at established 14 permanent monitoring 11 of the 14 plots. Very few balsam plots to measure balsam woolly adelgid woolly adelgid adults were found per damage and overall population plot (Table 12). However, the population changes. These plots are located within had increased at one plot, decreased at the nine Provincial ecoregions and three and no change was found at the whenever possible paired with existing remaining seven plots (Figure 18). Forest Inventory research permanent sample plots in order to compare the One of the most important natural impact of the adelgid on the growth, factors limiting adelgid populations is volume, and yield of balsam fir (Figure temperature. Mortality of overwintering 17). nymphs increase as temperatures dip below -20ºC and temperatures of -30ºC Each spring, adult adelgid populations or lower are fatal. Late spring frosts will are measured and overall tree condition also kill exposed feeding nymphs. So is rated and placed into one of four the recorded decreases weren’t damage classes (Nil, Light, Moderate unexpected due to the cold winter and Severe). Tree height and diameter temperatures measured at the plots are measured every other year. A data during 2010-2011(Figure 19). logger was also placed in each plot to measure annual temperatures.
28
Figure 17: Locations of Forest Health balsam woolly adelgid (Adelges picea) permanent monitoring plots.
Figure 18: Results of 2011 population monitoring at balsam woolly adelgid (Adelges picea) permanent monitoring plots.
29 Table 12: Summary balsam woolly adelgid (Adelges picea) permanent monitoring plot surveys conducted by Forest Health in Nova Scotia from 2010 - 2011.
Total Living Plot Plot Location County Adults Number 2010 2011 1 Liscomb Guysborough NA NA 2 Canoe Lake Yarmouth 1 0 3 Economy Cumberland 0 0 4 Fielding Road Inverness 0 0 5 Keppoch, Mayfield Road Antigonish NA 0 6 McRae Road Victoria 0 0 7 Mount Merrit Road Queens 15 0 8 Park Spur Road Inverness 0 NA 9 Pleasant Valley Road Halifax 0 0 10 Riversdale Colchester 0 0 11 Sand River Cumberland 0 0 12 Spry Bay Halifax 0 0 13 St. Josephs Richmond 2 0 14 Truro Watershed Colchester 0 5
Varying levels of overwintering nymph mortality between -20 to -30oC
Figure 19: Minimum temperatures (oC) recorded at balsam woolly adelgid (Adelges picea) permanent monitoring plots from November 2010 to April 2011.
30 Balsam Twig Aphid – Mindarus abietinus (Koch) The balsam twig aphid is a small, pale honeydew. This honeydew gives the green aphid that feeds primarily on needles a shiny appearance, but is balsam fir but may also attack Fraser fir, usually washed off by rain. However, it white fir and spruces. It is a major pest also provides a growth medium for sooty of firs grown for Christmas trees but is mold, which turns the needles and twigs considered a secondary forest pest as it black. does not cause tree mortality. It is widely distributed throughout Europe Forest Health monitors twig aphid and North America. Outbreaks are populations in a general way by generally short in duration as assessing their presence on balsam fir populations tend to quickly build and fall. branch samples collected for our balsam fir sawfly survey. This survey is not a Aphid feeding results in curled and predictive survey; it simply quantifies the distorted needles which reduces the damage that occurred the previous marketability and value of Christmas summer. Each branch is visually trees. Feeding can also cause inspected for balsam twig aphid damage roughened bark on the twigs. Extensive (Table 13). In 2011, of the 123 sites feeding can cause a general decline and surveyed, there were no sites with reduced tree vigor, yet in many cases it balsam twig aphid affected shoots is simply cosmetic. The aphids also (Figure 20). produce a sticky material known as
Table 13: Summary of balsam twig aphid (Mindarus abietinus) damage surveys conducted by Forest Health in Nova Scotia from 2003 to 2011.
Number Number of Sites with Balsam Twig Number (%) of Aphid Affected Shoots Year of Sites Positive Low Moderate High Sampled Zero Sites 1-33% 34-66% >67% 2003 659 105 (15.9) 554 98 7 0 2004 669 32 (4.8) 637 29 3 0 2005 411 45 (10.9) 366 42 3 0 2006 427 69 (16.2) 358 62 7 0 2008 42 1 (2.4) 41 1 0 0 2009 46 2 (4.3) 44 2 0 0 2010 127 4 (3.1) 123 4 0 0 2011 123 0 (0) 123 0 0 0
31
Figure 20: Results of the 2011 balsam twig aphid (Mindarus abietinus) damage survey.
Balsam Gall Midge – Paradiplosis tumifex (Gagné) Balsam gall midge is native to North dry, dropping off prematurely in the fall. America. It is not considered a Repeated severe infestations can cause significant forest pest but is one of the tree growth loss but does not result in most serious pests of balsam fir in mortality. If infested Christmas trees are Christmas tree stands. These tiny, 4 mm not to be harvested for another three to long, orange flies occur throughout the four years, they may outgrow the range of balsam and Fraser fir. They damage. were first recorded in eastern Canada in 1938 and since then, they have been Forest Health monitors balsam gall reported regularly. Infestations are midge populations in a general way by generally of short duration, lasting assessing their presence on balsam fir approximately three years. branch samples collected for our balsam fir sawfly survey. This survey is not a Damage appears on current-year predictive survey; it simply quantifies the needles. Larvae initiate the formation of damage that occurred the previous galls, which appear as swellings at the summer. Results show that there has base of the needles. Each gall contains been minimal damage in the Eastern a larva feeding on the needle’s internal and Central Regions of the province tissue. Galled needles turn yellow and (Table 14, Figure 21).
32 Table 14: Summary of balsam gall midge (Paradiplosis tumifex) damage surveys conducted by Forest Health in Nova Scotia from 2003 to 2011.
Number Number of Sites with Balsam Gall Number (%) of Midge Affected Shoots Year of Sites Positive Low Moderate High Sampled Zero Sites 1-33% 34-66% >67% 2003 659 9 (1.4) 650 9 0 0 2004 669 1 (0.1) 668 1 0 0 2005 411 14 (3.4) 397 14 0 0 2006 427 32 (7.5) 395 31 1 0 2008 42 2 (4.8) 40 2 0 0 2009 46 12 (26.1) 34 10 2 0 2010 127 16 (12.6) 111 16 0 0 2011 123 1 (0.8) 122 1 0 0
Figure 21: Results of the 2011 balsam gall midge (Paradiplosis tumifex) damage survey.
Insect Pests of Hardwoods
Gypsy Moth - Lymantria dispar (L.) The gypsy moth was introduced to North foliage of hundreds of plant species America from Europe in 1869 in causing defoliation and stress. Massachusetts. It is a serious pest of Defoliation may result in tree mortality, deciduous species. Larvae feed on the
33 growth reduction, and higher presence of gypsy moth has always vulnerability to secondary pests. been constant in areas where they are established. The first gypsy moth egg mass in Nova Scotia was detected in Yarmouth in As it is a quarantine pest, the gypsy 1981. Currently, Nova Scotia has an moth is under surveillance by the CFIA. established population of gypsy moth in Forest Health monitors gypsy moth the Western Region. Population levels populations throughout the province have fluctuated over time however, the using pheromone traps.
Pheromone Trap Survey In 1998, a pheromone monitoring survey results trap catches remained system was initiated to detect gypsy fairly stable with changes detected in moth adults. Since that time PDO’s and two counties within the CFIA regulated Forest Health staff have deployed zone: an increase in Digby County and individual multipher traps at designated a decrease in Annapolis County. sites province wide (Figure 22, Table Based on our delta trap survey the only 15) and delta traps in various towns town that continues to show a outside the CFIA regulated zone (Figure population increase is New Glasgow in 23, Table 16). Pictou County. However, since 2009 the average moth catch per trap has been In 2011 we placed 19 traps. 68% were on the decline. In 2011, this trend has positive up from 58% the year before held true with an average moth catch of with a total of 3188 moths caught up nine down from 14 moths per trap in from 3093 recorded in 2010. The 2010. permanent multipher trap survey provides a snapshot of the population across the province; based on our 2011
34 Table 15: Summary of gypsy moth (Lymantria dispar) permanent, multipher pheromone trap surveys conducted by Forest Health in Nova Scotia 1998 to 2011.
Number of Traps Number Number of Moths/Trap Mean (%) Total Year Low Moderate High Trap Placed Returned Positive Zero Moths 1 - 100 101 - 300 >300 Catch Traps 1998 23 22 3 (13.6) 19 1 1 1 717 32.6 1999 22 22 6 (27.3) 16 4 0 2 971 44.1 2000 21 21 9 (42.9) 12 6 0 3 2136 101.7 2001 21 21 11 (52.4) 10 8 1 2 2080 99.1 2002 22 22 15 (68.2) 7 11 1 3 3581 162.8 2003 24 24 16 (66.7) 8 12 1 3 2804 116.8 2004 23 21 14 (66.7) 7 10 1 3 1873 89.2 2005 21 14 8 (57.1) 6 5 1 2 1559 111.4 2006 22 21 12 (57.1) 9 7 3 2 2029 96.6 2007 21 18 12 (66.7) 6 7 2 3 2702 150.1 2008 19 19 11 (57.9) 8 8 0 3 3739 196.8 2009 21 19 12 (63.2) 7 6 4 2 2546 134.0 2010 20 19 11 (57.9) 8 5 1 5 3093 162.8 2011 20 19 13 (68.4) 6 7 2 4 3188 167.8
Figure 22: Results of the 2011gypsy moth (Lymantria dispar) permanent trap survey.
35
Figure 23: Results of the 2011 gypsy moth (Lymantria dispar) delta trap town survey.
Table 16: Summary of gypsy moth (Lymantria dispar) delta pheromone trap surveys conducted by Forest Health in Nova Scotia 2000 to 2011.
2000 2001 2002 2003 Moths Moths Moths Moths Town Traps Traps Traps Traps per per per per Returned Returned Returned Returned Trap Trap Trap Trap Advocate 10 1.8 10 2.1 10 0.7 10 9.1 Amherst 8 2.3 7 3.6 9 7.6 8 5.5 Antigonish 10 0.4 10 0.6 10 0.4 10 0.7 Baddeck 9 0 10 0 9 0.6 10 0.1 Big Pond 10 0 10 0 10 0 10 0 Cheticamp 9 0 10 0 10 8.9 9 0.1 Five Islands 9 1.8 10 2.5 10 1.1 10 9.7 Guysborough 10 0.1 9 0 10 0 10 0.3 Inverness 8 0.1 10 0 8 0.3 10 0 Mulgrave 8 0.1 9 0.2 10 0 9 0 New Glasgow 10 0.2 10 0.8 10 0.6 10 1.9 Parrsboro 10 12.2 10 8.9 9 15.1 10 13.8 Pictou 8 0.3 9 0.2 10 0.1 10 0.3 Sheet Harbour 9 0.1 10 0 10 0.2 Na Sherbrooke 10 0.1 10 0.2 10 0.2 10 0 Shubenacadie 9 0.3 10 0.4 10 0.9 9 2.3 Stewiacke 8 0.4 8 0.3 9 0.8 8 1.8 St. Peters 6 0 9 0 9 0 9 0.2 Tatamagouche 9 0.2 10 0.1 9 1.2 7 1.0
36 2000 2001 2002 2003 Moths Moths Moths Moths Town Traps Traps Traps Traps per per per per Returned Returned Returned Returned Trap Trap Trap Trap * Truro 10 1.7 10 1.6 9 6.8 25 5.6 2004 2005 2006 2007 Moths Moths Moths Moths Town Traps Traps Traps Traps per per per per Returned Returned Returned Returned Trap Trap Trap Trap ** Advocate 10 4.8 10 4.2 10 3.7 9 0.9 Amherst*** 13 4.4 15 3.8 To Antigonish 5 1.6 10 0.8 10 0.7 10 0.4 Baddeck 10 0 10 0.1 10 0 9 0 Big Pond 10 0.1 10 0 10 0 10 0 Cheticamp 10 0.1 10 1.2 10 0.1 10 0 Five Islands 9 11.8 10 5.2 10 11.6 10 9.7 Guysborough 10 0 10 0 10 0 10 0 Inverness 10 0.1 10 0.3 10 0.2 10 0 Mulgrave 8 0 10 0 10 0.1 10 0 New Glasgow 10 3.4 10 4.8 10 6.1 10 9.6 Parrsboro 9 14.8 10 17.8 To Pictou 10 0.4 10 0.5 10 0.4 10 0.5 Sheet Harbour 8 0.9 10 0.4 10 0.1 10 0.2 Sherbrooke 10 0.3 10 0.1 10 0 10 0 **** Shubenacadie 5 3.0 5 0 10 9.2 **** 12 8.4 Stewiacke 5 2.8 5 0 10 4.8 St. Peters Na 10 0 8 Na 10 0 Tatamagouche 10 2.6 8 2.6 8 3.8 10 1.9 * Truro 24 8.5 20 8.5 To 2008 2009 2010 2011 Moths Moths Moths Moths Town Traps Traps Traps Traps per per per per Returned Returned Returned Returned Trap Trap Trap Trap Advocate Ds Antigonish 10 0.7 10 1.3 10 0.7 10 0.7 Baddeck 10 0.2 9 0 10 0 10 0 Big Pond 10 0 10 0 9 0 10 0 Cheticamp 9 0.1 9 0 10 0 8 0 Five Islands Ds Guysborough 10 0.1 10 0.1 8 0 10 0 Inverness 10 0 7 0 10 0 8 0 Mulgrave 10 0.1 Na 9 0 9 0 New Glasgow 10 15.5 10 19.5 10 13.9 9 9.1 Pictou 10 1.8 10 0.4 10 0.4 10 0.5 Sheet Harbour 10 0.2 10 1.9 Ds Sherbrooke 10 0.3 10 0.4 10 0.2 10 0.5 Shubenacadie Ds Stewiacke Ds St. Peters 10 0 9 0 9 0.1 10 0 Tatamagouche 10 2.1 1 12 Ds * 30 traps were deployed at this site in 2003, 2004 and 2005. ** 20 traps were deployed instead of 10 at this site in 2004 and 2005. *** 20 traps were deployed instead of 10 at this site in 2005. 37 **** 5 traps were deployed instead of 10 at these sites in 2005 and 2007. Na = traps not deployed or information not available Ds = deleted from survey
Invasive Pests
Brown Spruce Longhorn Beetle - Tetropium fuscum (Fabr.) The brown spruce longhorn beetle is 2000. This order has been revised twice native to northern and central Europe since it was issued so that the present and was positively identified in Nova containment area now includes central Scotia in 1999. This is the only known Halifax County and very small adjacent occurrence of this beetle in North portions of Colchester and Hants America. It has been confirmed in red, Counties (Figure 24). The order Norway, white and black spruce. As part regulates the movement of high risk of a joint effort NSDNR works with the articles including spruce round logs, CFIA and CFS to monitor the beetle’s unprocessed wood chips (> 4cm), and spread within Nova Scotia through bark out of the containment area. pheromone trapping surveys. In 2008, the order was revised again mandating that a one kilometer To help prevent the spread of the beetle movement restriction be placed around a Ministerial Order, The Brown Spruce all positive locations outside of the Longhorn Beetle Infested Places Order, containment area. was issued by the CFIA in October
Figure 24: Brown spruce longhorn beetle (Tetropium fuscum) containment area 2011.
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Pheromone Trap Survey The 2011 detection survey for the brown been detected outside the province of spruce longhorn beetle continued to Nova Scotia. These six new finds brings include extensive trapping throughout the total number of positive sites outside Atlantic Canada. This year’s survey of the beetle containment area to 65. resulted in 20 positive sites outside the beetle containment area (Figure 25). Of Additional pheromone traps were also these positive sites, five are new for deployed throughout Atlantic Canada in Nova Scotia in the counties of Halifax, Prince Edward Island, New Brunswick Hants, and Luneburg (Figure 26). There and Newfoundland and Labradour. All, was also a positive location in New with the exception of the one positive in Brunswick located near a campground New Brunswick, were negative for in Kouchibouguac National Park (Figure brown spruce longhorn beetle (Figure 26). This is the first time the beetle has 27).
Figure 25: Positive sites (20) detected outside of the brown spruce longhorn beetle (Tetropium fuscum) containment area in 2011.
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Figure 26: New (circled) brown spruce longhorn beetle (Tetropium fuscum)
positive sites detected outside the containment area in 2011.
.
Figure 27: Brown spruce longhorn beetle (Tetropium fuscum) trap locations for Eastern Canada 2011. 40
Arthropods of Importance to Human Health
West Nile Virus West Nile virus is a viral infection Mosquito surveillance has been transmitted by mosquitoes. Mosquitoes suspended due to lack of West Nile pick up the virus from feeding on birds virus activity, but will be re-introduced if and then can transmit the illness to the virus is again detected within wild humans. There have been no human bird populations. As of 2010, dead birds cases of West Nile virus acquired in in Nova Scotia are no longer tested for Nova Scotia. West Nile virus. No birds have tested positive since 2003. Tick Survey Until September of 2011, province-wide passive surveillance was being Currently, there are five established conducted by the Nova Scotia populations of Blacklegged ticks in Nova Department of Health and Wellness. Scotia: Specimens were welcome to be Pictou County - areas around submitted by the public, veterinarians Melmerby Beach, Egerton, Kings and physicians to Forest Health or the Head, and Pine Tree; Museum of Natural History for Lunenburg County - (Blue Rocks, identification. The focus has now shifted Garden Lots, Heckmans Island, solely to active field work to identify First Peninsula as well as the areas where tick populations are areas immediately surrounding expanding. Forest Health staff now visit them; sites from which multiple ticks have Halifax County - Admirals Cove in been submitted and check squirrels, Bedford; mice, chipmunks and other small Shelburne County - Gunning mammals for ticks. The Department of Cove and; Health and Wellness no longer needs to Yarmouth County - Gavelton receive ticks for testing or surveillance area. purposes. A population is considered established In 2011, 1500 ticks were submitted to when more than one life stage of the Forest Health for identification, the blacklegged tick has been found in an majority, 850 being black legged ticks area. (formerly called deer ticks - Ixodes scapularis) (Table 17).
41 Table 17: Number of tick identification inquiries from 2002 to 2011.
Number of Tick Identification Inquiries 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011* 45 170 186 190 569 635 1191 1350 1384 1500 *Passive surveillance was discontinued by the Department of Health and Wellness on September 30, 2011 in favour of increased active surveillance and other more valuable data collection methods.
Pest Identification Service
Since 1995, Forest Health staff have and control strategies, selecting control coordinated the identification of pests options, and determining overall risk. In affecting Nova Scotia’s forests. 2011, 100 inquiries were answered. Of Specimens were submitted for these inquiries, 25 (24.8 %) dealt identification by private landowners, directly with our forest resource i.e. forestry companies, and district PDO’s. plantations and woodlots; the remaining 76 (75.3 %) were general homeowner Correct and timely pest identification is inquiries (Table 18). essential for the planning of monitoring
Table 18: Summary of pest identification inquiries to Forest Health from 2001 to 2011
Number of Pest Identification Inquiries Inquiry Related to 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 General Identification 120 170 154 141 131 166 132 211 125 86 76 Forest and Urban Trees 152 159 118 91 68 77 69 0 32 44 25 Forest Health Surveys NR NR 269 270 225 296 NR NR 2 5 0 Fungal/Abiotic* 36 42 45 21 23 10 0 Total Inquiries Received 272 329 541 502 460 581 246 232 182 145 101 *From 2001 - 2004 fungal/abiotic identifications were incorporated as part of forest and urban tree. NR = not recorded
Communications
Newsletter: Insectary Notes Forest Health publishes Insectary offices in all levels of government, in Notes, a bi-monthly newsletter. It every province of Canada and some originated as a publication chiefly for States. The objective of this publication NSDNR employees, those interested in is to communicate current information in forestry and forest pests and a timely manner using a recognized and entomologists. Through nineteen years easy to understand format. in publication, it has grown to reach
42 Website The NSDNR Forest Health section Future plans for the website include website, increasing the number of fact sheets http://www.gov.ns.ca/natr/forestprotectio and including links to other sites within n/foresthealth/default.asp, was launched the government site that would be of in March of 2003. It presently contains use to clients. fact sheets for various forest pests.
Extension and Outreach Forest Health delivers programs for Woodlot Owner of the Year Awards elementary school aged students. The each fall; various spring field days and student education program, along with National Forest Week in September; as programs for adults and stakeholders, well as yearly information sessions as has grown into a significant part of the part of the Woodland Owner overall Forest Health work pan. Conferences and Christmas Tree Producer Associations technical Forest Health participates in the Kids in sessions and field days. the Forest program, held as part of the
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APPENDIX I – GLOSSARY
Abiotic - non-living chemical and physical factors in the environment.
Aerial Survey - visual assessments, made from the air, of forest disturbances caused by biotic and abiotic agents. These surveys are used to record the location, extent and severity of damage, possible damaging agent and the host tree species affected by the damaging agent.
Arthropod –an animal that lacks a backbone, has a segmented body, and hollow jointed legs i.e. insects, spiders, and crustaceans.
Biotic - of or relating to living organisms.
Conifer – cone-bearing trees having needles or scale-like leaves, usually evergreen, and producing wood known commercially as 'softwoods'.
Containment Area - application of phytosanitary measures in and around an infested area to prevent spread of a pest.
Deciduous – referring to a plant that annually sheds its leaves.
Defoliation – loss of leaves, as occurs in natural shedding or from the feeding activities of insects and other plant feeders.
Delta Trap – a trap type used to monitor gypsy moth and many other key insect pests consisting of a wax-covered cardboard housing, a pheromone lure, and an adhesive. The lure is saturated with female sex pheromone which is attractive to male moths. Once inside the trap, males are immobilized by the adhesive coating.
Detection Survey - survey conducted in an area to determine if pests are present.
Dormant - to become inactive during winter or periods of cold weather.
Ecoregions –provincial climatic regions that support distinctive vegetation communities and physiographic patterns.
Ecosystem - a term used to describe a natural unit that consists of living and non-living parts which interact to form a stable system.
Ectoparasite - an organism that lives part or all of its life on a different organism, the host, and from which it derives part or all of its sustenance.
Egg Mass - a group of eggs deposited by the female insect which are adjacent to each other or overlapping as opposed to eggs laid singly.
44 Endoparasite - an organism that lives part or all of its life in a different organism, the host, and from which it derives part or all of its sustenance. Fixed Radius Plot - a controlled cruise method where small plots of a fixed size are used to sample a portion of a forest area to obtain information (such as tree volume) that can be used to describe the whole area.
Gall - an abnormal swelling of plant tissue caused by insects, microorganisms, or external injury.
Genus (plural: genera) - a group of closely related species e.g. spruce are grouped in the genus Picea.
Gouting - excessive swelling of a branch or shoot; often accompanied by misshapen needles and buds; frequently caused by the balsam woolly adelgid on true firs.
Ground Survey - the objectives of the ground surveys are: to identify the pest organism; determine the host species and locate additional trees affected by the pest in the immediate vicinity before visible crown symptoms appear. It is possible, after obtaining these data, to correct the gross aerial survey data to more accurately reflect the pest conditions within the survey area.
Hardwood - trees which are generally deciduous, broad leafed species such as oak, birch, alder or maple.
Host - any organism upon or within which another organism lives.
Infestation - the presence of a large number of pest organisms in an area.
Instar - the stage of an insect's life between consecutive moults e.g. the first instar is between hatching from the egg and the first moult.
Introduced Species - a species that does not naturally occur in a given area, but has instead been brought in by other means.
Invasive Alien Species– are plants, animals and micro-organisms that, when introduced outside of their natural past or present distribution spread and cause serious and often irreversible damage to Canada's native ecosystems, economy and society.
L2 – abbreviation for second instar larvae; the larva after the first moult. Spruce budworm and jack pine budworm overwinter in this life stage.
Larva (plural: larvae) - the immature form of insects that develop through the process of complete metamorphosis including egg, several larval stages, pupa, and adult. In mites, the first-stage immature is also called a larva.
Metamorphosis - the change in form that takes place as insects grow from immatures to adults.
45 Ministerial Order - declares a specific area to be infested with a quarantine pest e.g. brown spruce longhorn beetle (BSLB), identifies the area and materials to be regulated, and restricts the movement of regulated articles that could transport the BSLB.
Moult - in insects and other arthropods, the shedding of skin before entering another stage of growth.
Monitoring - carefully watching and recording information on the activities, growth, development, and abundance of organisms or other factors on a regular basis over a period of time, often utilizing very specific procedures.
Mortality Agent - any biotic or abiotic agent that causes damage to a tree, or other plant of concern.
Multipher Trap - a non-sticky, reusable trap in which moths are attracted to the pheromone lure and killed with an insecticide strip.
Native Species - of local origin, not intentionally or accidentally introduced.
Nymph - the immature stage of insects such as aphids and adelgids that hatch from eggs and gradually acquire adult form through a series of moults without passing through a pupal stage.
Outbreak - a sudden, large increase in an insect’s population.
Over-mature - those trees or stands past the mature stage.
Overwinter – a period of rest or hibernation by which insects survive the winter.
Parasite - an organism that lives part or all of its life in (endoparasite) or on (ectoparasite) a different organism, the host, and from which it derives part or all of its sustenance.
Parasitize - to live on or in a host as a parasite.
Pest - an organism that reduces the availability, quality, or value of some human resource.
Pheromone - a substance released by an organism to affect the behavior or development of other members of the same species; sex pheromones that attract the opposite sex for mating are used in monitoring certain insects.
Pheromone Trap - a trap which utilizes either a natural or, more typically, a synthetic insect sex attractant pheromone; these traps are usually species specific.
Phytosanitary Measures - any legislation, regulation or official procedure having the purpose to prevent the introduction and/or spread of pests.
Plantation - a group of cultivated trees.
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Population - A group of organisms of one species that interbreed and live in the same place at the same time.
Predictive Survey - estimate expected defoliation in the coming year. These surveys can be used to forecast stand level defoliation, and will help determine when and where to prescribe stand treatments.
Pupa - the non-feeding, inactive stage between larva and adult in insects with complete metamorphosis.
Quarantine Pest - a pest of potential economic importance to the area endangered thereby and not yet present there, or present but not widely distributed and being officially controlled.
Regulated Area (Zone) - an area, created by the CFIA, into which, within which and/or from which plants, plant products and other regulated articles are subjected to phytosanitary regulations or procedures in order to prevent the introduction and/or spread of quarantine pests or to limit the economic impact of regulated non-quarantine pests.
Regulated Article - any plant, plant product, storage place, packaging, conveyance, container, soil and any other organism, object or material capable of harboring or spreading pests, deemed to require phytosanitary measures, particularly where international transportation is involved.
Sample - the portion of a population collected in a prescribed manner upon which a judgment is made about the entire population.
Secondary Pest – an injurious insect capable of damaging only dying trees or those of low vigour.
Significant Forest Pest – forest pests capable of killing or severely damaging trees over large areas.
Softwood - cone-bearing trees with needle or scale-like leaves such as balsam fir, eastern white cedar and Jack pine.
Species - a group of individuals that have their major characteristics in common and (usually) can only breed with each other.
Survey - an official procedure conducted over a defined period of time to determine the characteristics of a pest population or to determine which species occur in an area.
Terminal - the growing tip of a stem, especially the main stem.
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