Introduction to Priority pests and diseases year 3

Transcription

1 Introduction to Priority pests and diseases year 3 Suzanne Sancisi Frey Forest Research NE and NW England

2 Pest and disease training Introduction On-line presentations with voice overs Webinars + Q&A On-line forum for questions and discussion about pests and diseases

3 Year 3 priority pests and diseases: N. East and N. West England: Bronze birch borer Chestnut blight Pine processionary moth Oak processionary moth Oriental chestnut gall wasp

4 David Cappaert, Michigan State University, Bugwood.org 6-12 mm long Bronze Birch Borer Agrilus anxius Not here yet Native to ( North America - most serious threat to Birch Opportunistic - attack stressed trees Red-Necked Longhorn Beetle European birch has no resistance Predict devastating effects to our birch

5 Photo:USDA FIDL leaflet 111 G. Heaton Photo:USDA FIDL leaflet 111

6 Impact Spread of the invasive population may be rapid and unmanageable, resulting in large scale outbreaks The adult beetles are strong fliers Plenty of hosts It can tolerate a wide climatic range, such as that found throughout Britain and much of Europe Eradication or containment would be difficult due to the cryptic nature of its life cycle, If it did get here we would expect widespread mortality of birch in forests, nurseries and cities

7 Oriental chestnut gall wasp (Dryocosmus kuriphilus) mm long Photo - Forest Research Institute/Bugwood.org D. kuriphilus is an important insect pest worldwide on sweet chestnut Possibly native to China In USA and in Europe since 2002 and was found Kent and Herts just last year Attacks vegetative buds and forms galls, disrupts twig growth, reduces fruiting and disrupts coppicing in sweet chestnut Severe infestations may result in the decline and death of chestnut trees.

8 Galls and leaf Photograph courtesy of Forestry Commission / Matteo Maspero distortion

9 Inside the gall

10 Oak Processionary Moth ( Photo Ralph Parks and FR Native to Central and Southern Europe Present in the UK since 2006 Form long lines, or processions, in oak trees

11 W. + S.W. London + Surrey 2006 E. London 2014 S. London 2012

12 Oak Processionary Moth (Thaumetopoea processionea) Threat Threat OPM caterpillars reduce the health of oak trees by feeding on the leaves Large OPM populations can strip entire trees bare of leaves Vulnerable to attack by other pests and diseases Less able to withstand adverse environmental events such as drought and flood

13 Oak Processionary Moth (Thaumetopoea processionea) Public Health Risk 0.1 mm The caterpillars are covered with irritating hairs (thaumetopoein), Can cause itching skin rashes, sore throats, breathing difficulties and eye problems. Detach and be blown around by the wind. The hairs can be shed as a defence mechanism. Do not touch or approach inhabited or abandoned nests or caterpillars Do not try removing nests or caterpillars yourself

14 Oak Processionary Moth Signs and Symptoms and ID June to mid July Photo Ralph Parks and FR Silken trails semi-spherical or teardrop-like in shape Photo Ralph Parks and FR Distinctive white, silken webbing nests anywhere on trunks / branches of oak trees Leave white silken trails on trunks and branches in early summer The nests and trails become discoloured and are more difficult to see Spend the days in nests and emerge at dawn and dusk to feed

15 Pine processionary moth Thaumetopoea pityocampa John H. Ghent Copyright: USDA Forest Service, Bugwood.org D.D. Cadahia : Subdireccion General de Sanidad Vegetal, Bugwood.org Brown moth which is difficult to tell apart from many other native moths The caterpillar is hairy and coloured orange-brown with blue bands. They form nose to tail processions and bear irritating hairs Feed on the needles of pine trees and other conifer tree species. Large numbers defoliate trees, weakening them and making them more susceptible to other pests or diseases

16 Current distribution Native to Mediterranean regions, N. Africa, Middle East and S. Europe Not here yet But possibly heading our way One population in a UK nursery in 1995 on imported Scots pine One adult moth trapped in Berkshire in 1996

17 Signs and symptoms Fresh nests Anna Perez, Forest Research

18 Chestnut blight (Cryphonectria parasitica) Asian origin Confirmed in Warwickshire, UK in 2011 on sweet chestnut (Castanea sativa) trees planted for nut production More sites later confirmed - all on trees from the same source Not present now

19 Chestnut blight (Cryphonectria parasitica) Fungal wound pathogen Stems or branches are girdled The dead bark becomes visible as a sunken canker Above the canker, leaves wilt and turn brown, but remain attached Epicormic growth below the canker

20 Sweet Chestnut blight (Cryphonectria parasitica) Symptoms Masses of yellow-orange to reddishbrown pustules, the size of a pin-head, develop on infected bark. These fruit bodies erupt through lenticels and exude long, orange-yellow tendrils of spores in moist weather. Plant Health England

21 Year 3 priority pests and diseases: N. East and N. West England: Bronze birch borer Chestnut blight Pine processionary moth Oak processionary moth Oriental chestnut gall wasp

22 Pest and Disease symptoms calendar Signs and symptoms calendar for Observatree priority P&DS (visibility/appearance of signs and symptoms are dependent on weather; for P&Ds not here yet behaviour and timings are not fully determined) January February March April May June July August September October November December Dothistroma needle blight Needle symptoms/banding most obvious now Look for the caterpillars especially at dawn/dusk and signs of feeding damage Check traps as adult moths now flying Oak processionary Moth Look for old nests and egg plaques while leaves are absent Survey for nests/trails while they are still white Survey for nests in pine trees Pine processionary moth Adults flying - check traps Caterpillars are active - mainly at night but look for feeding damage on needles Caterpillars are active - mainly at night but look for feeding damage on pine needles Chestnut gall wasp Look for brown woody galls and retained leaves with "scrunched up" appearance Current years galls (green and/pink/red) visible for the season - look for leaf distortion too Look for brown, woody galls and retained leaves with "scrunched up" appearance Leaf infections visible Chalara leaf infections most visible now Look for bark lesions while leaves are absent Chalara Ash dieback Look for bark lesions while leaves are absent Look for the fruiting bodies on rachis in the litter Asian Longhorn beetle Look for adult beetles, signs of feeding damage on leaves and fresh exit holes in upper trunk and branches Larvae active all year round - look for frass and exit holes when leaves are absent Citrus longhorn beetle Look for adult beetles, signs of feeding damage on leaves and fresh exit holes in lower trunk and exposed roots Larvae active all year round - look for frass and exit holes when leaves are absent Redneck longhorn beetle Larvae active all year round - look for frass and exit holes when leaves are absent Look for adult beetles, signs of feeding damage on leaves and fresh exit holes Horse chestnut leaf miner pale and brown leaf mines visible on leaves Phytophthora lateralis Symptoms (bark lesions and foliage death) can be visible all year round Phytophthora austrocedri Symptoms (bark lesions and foliage death) can be visible all year round Look for wilting and discoloured (yellow) leaves and abnormal leaf fall Plane wilt Bark lesions visible all year round Look for rows of eggs along leaf veins, foliar feeding damage, small black specks of frass on leaf undersides, wingless nymphs and nymphal skins Plane lace bug Adults overwintering Ist and 2nd generation adults emerge to produce further generations and then overwinter to start cycle again in the spring Look for rows of eggs along leaf veins, foliar feeding damage, small black specks of frass on leaf undersides, wingless nymphs and nymphal skins Oak lace bug Adults overwintering in leaf litter Ist and 2nd generation adults emerge to produce further generations and then overwinter to start cycle again in the spring Larva/larval galleries below bark+other bark signs/symptoms e.g. D shaped exit holes present all year round Adults emerge and are present in canopy Larvae/larval galleries below bark+other bark signs/symptoms e.g. D shaped exit holes present all year round Bronze Birch Borer When trees are in leaf look for thinning, yellowing and stunted leaves in upper crown and also twig and branch dieback and epicormic growth Larva/larval galleries below bark+other bark signs/symptoms e.g. D shaped exit holes present all year round Adults emerge and are present in canopy look for feeding damage on leaves Larvae/larval galleries below bark+other bark signs/symptoms e.g. D shaped exit holes present all year round Emerald ash borer When trees are in leaf look for thinning, yellowing and stunted leaves in upper crown and also twig and branch dieback and epicormic growth Great spruce bark beetle Any stage of the life cycle may be seen throughout the year (adults externally and larvae/pupae within galleries under bark). Adults only active at temperatures above 12 degrees C. Look for resin tubes and resin bleeds on bark. Browning and death of foliage over some/all of the crown Bark lesions more visible in the winter Look for leaf collapse and patches of retained dead foliage and also epicormic growth Bark lesions more visible in the winter Chestnut blight Look for small orange fruiting bodies on the bark lesions from spring through to autumn (you may need hand lens). Yellow tendrils may also be present in wet conditions European mountain ringspot virus Look for foliar symptoms while the tree is in leaf; yellow mottling/speckling, yellow ringspots, oakleaf discolouraton pattern and any signs of general decline in the tree Old bleed stains may be visible Fresh bleeds Old bleed stains may be visible Fresh bleeds Old bleed stains may be visible Acute oak decline Other signs and symptoms such as D shaped exit holes, larval galleries beneath bark, callus growth over galleries and signs of general tree decline may be visible all year round

23 Thank you!! Suzanne Sancisi-Frey (Forest Research)