Extension Note BC Journal of Ecosystems and Management British Columbia’s Northern Interior Forests Dothistroma Stand Establishment Decision Aid

Larry McCulloch1 and Alex Woods2 Introduction

Dothistroma needle blight, also known as red band needle blight, is caused by the fungus Dothistroma septosporum. It affects over 60 species of pine in 45 countries and is considered the most destructive pine needle disease in the world. All pine species native to British Columbia are susceptible and the fungus is widely distributed wherever host species can be found. Infection is caused by rain splash and air dispersal of the spores. In the southern hemisphere, it has been a major problem for decades. In British Columbia, however, damage levels from this pathogen have historically been low. Recent widespread defoliation, mortality (including mature tree mortality), and plantation failure caused by Dothistroma in the northwest portion of the province may be a result of changing climatic conditions that allow the fungus to develop in a way that was not previously possible. The Stand Establishment Decision Aid (seda) format has been used to extend information on a variety of vegetation and forest health concerns in British Columbia. The two-page seda presented in this extension note was developed to summarize information that provincial forest managers will need to mitigate the impacts of Dothistroma needle blight. The first page provides information on susceptible stand types, disease biology, hazard ratings, and appropriate management practices. The second page outlines forest productivity considerations and risks to human health. A resource and reference list that readers can use to find more detailed information is also included. Most reference material that is not available online can be ordered through libraries or the Queen’s Printer at: www.qp.gov.bc.ca Acknowledgements The preparation and publication of this decision aid was supported by the British Columbia Ministry of Forests and Range through the Forest Investment Account–Forest Science Program. keywords: climate change, Dothistroma needle blight, Dothistroma septosporum, forest health, red band needle disease, tree species deployment.

Contact Information 1 Principal, LM Forest Resource Solutions Ltd. PO Box 880, Smithers, BC V0J 2N0. Email: [email protected] 2 Forest Pathologist, BC Ministry of Forests and Range, Northern Interior Region, Regional Service Centre, Bag 6000, 3333 Tatlow Road, Smithers, BC V0J 2N0. Email: [email protected]

article received: June 26, 2007 article accepted: October 3, 2008

JEM — Vo l u me 10, Nu m b e r 1 Published by Forrex Forum for Research and Extension in Natural Resources McCulloch, L. and A. Woods. 2009. BritishJ EMColumbia’s — Vo l u northernme 10, Ninterioru m b e r forests: 1 Dothistroma Stand Establishment 1 Decision Aid. BC Journal of Ecosystems and Management 10(1):1–3. www.forrex.org/publications/jem/ISS50/vol10_ no1_art1.pdf mcculloch and w o o d s

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esources Society and the Province of British Columbia Columbia British of Province the and Society esources (Accessed February 2009). (Accessed R ociety and of all contributing copyright owners. This publication publication This owners. copyright contributing all of and ociety S does not warrant their and accuracy or disclaims expressly any reliability, esources esources uite 702, 235 1st Avenue, Kamloops, BC Kamloops, Avenue, 702, 235 1st uite R , S 1488-4674. Articles or contributions in this publication may be reproduced in in reproduced be may publication this in contributions or Articles 1488-4674. A review. Forest Pathology 34:163–185. Pathology Forest A review. Forrex atural atural

N xtension in Natural Natural in xtension nternet without the written consent of of consent written the without nternet issn Forrex The information and opinions expressed in this publication are those of the respective authors authors respective the of those are publication this in expressed opinions and information The and thereto. relation in liability E © 2009 Copyright in this article this is© 2009 Copyright in property the of and training, educational, in recipient the to charge of free use for form print or electronic acknowledged. fully are authorship and source their that provided activities not-for-profit media, or forms other to application translation, adaptation, reproduction, However, or resale, use, commercial for part, in or whole in works, these of use other any or of consent written the requires redistribution, in in the over public the to accessible made be not may herein contributions and articles the and I (Accessed February 2009). m (Accessed Ecological Monographs 69(3):375–407. 69(3):375–407. Ecological Monographs 79:892–897. Forestry Chronicle www.for.gov.bc.ca/ 55(9):761–769. BioScience change? climate to blight related epidemic hfp/fft/scientific-articles/articles/Woods%20et%20al%202005_Dothistroma%20and%20 f Climate%20Change.pd Natural Resources Canada, Canadian Forest Service, Victoria BC. www.pfc.cfs.nrcan.gc.ca/ BC. Victoria Service, Forest Canadian Canada, Resources Natural February 2009). diseases/ctd/index_e.html (Accessed toxin: Ecology 87:2773–2786. species distribution in British Columbia. www.for.gov.bc.ca/hfd/pubs/Docs/Srs/SRseries. 6. Series Special Report No. BC. Victoria, ht Phytopathology 57:437–441. Epidemiology and control. www.na.fs.fed.us/spfo/ 143. No. and Disease Insect Leaflet Forest Nebr. Lincoln, Service, pubs/fidls/dothistroma/doth.ht in Pinus contorta: climate to

Woods, A. 2003. Species diversity and forest health in northwest British Columbia. British Columbia. health in northwest and forest Species diversity 2003. A. Woods, needle Dothistroma an unprecedented Is 2005. Hamann. A. and Coates, K.D. A., Woods, Resource and reference list and reference Resource of diseases tree Common British Columbia. 1996. Wallis. and G. Morrison, D. E., Allen, band) needle blight (red Dothistroma of dothistromin pines and the 2004. R.E. Bradshaw, and tree effects of ecosystem on change climate Potential 2006. Wang. and T. A. Hamann, BC Ministry of of British Ecosystems Columbia. Forests, 1991. Pojar. and J. D. Meidinger, pines: needle and ponderosa Dothistroma blight ofAustrian 1967. G.W. Peterson, needle Dothistroma blight US Department of Forest of 1982. Agriculture pines. ______. Genetic responses 1999. Jr. Hamilton, and D.A. Spittlehouse, D.L. Ying, C.C. G.E., Rehfeldt,

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JEM — Vo l u me 10 Nu m b e r 1 3 Test Your Knowledge . . .

British Columbia’s Northern Interior Forests: Dothistroma Stand Establishment Decision Aid

How well can you recall some of the main messages in the preceding Extension Note? Test your knowledge by answering the following questions. Answers are at the bottom of the page.

1. New infections are likely to be highest: a) In the fall, when it is cool and moist b) In the summer during cool dry periods c) During warm, humid conditions in the growing season

2. Only the current years’ pine needles are susceptible. a) True b) False

3. The best strategy for avoiding Dothistroma infections on dry sites is to: a) Avoid clearcutting b) Plant an exotic pine species c) Spray the area with copper fungicides d) Plant Douglas-fir e) Plant a mix of pine, spruce, and Douglas-fir

ANSWERS

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2 JEM — Vo l u me 10, Nu m b e r 1