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Oregon swiss needle cast workshop

Scion is the leading provider of forest-related knowledge in New Zealand
Formerly known as the Forest Research Institute, Scion has been a leader in research relating to forest health for over 50 years. The Rotorua-based Crown Research Institute continues to provide science that will protect all forests from damage caused by insect pests, pathogens and weeds. The information presented below arises from these research activities.

From Forest Health News 147, December 2004.

A one day workshop was held in Eugene, Oregon, on 16 November entitled “Growing Douglas-fir in the Swiss needle cast zone”. This disease, caused by the needle fungus Phaeocryptopus gaeumannii , has a significant impact on the growth of Douglas fir in New Zealand (FHNews 114: 1–2), and is also the cause of serious concern to managers of Douglas fir plantations along the coastal 30-km-wide strip of western Oregon. The workshop was organised by Doug Mainwaring (Oregon State University) and others from the Oregon Swiss Needle Cast Cooperative (a collective of university, company, and US Forest Service representatives), and was introduced and chaired by a former director of the Cooperative, Greg Filip (US Forest Service). In a series of presentations, various researchers described their latest findings on the cause, impact (on both growth and wood properties), distribution, biology, and epidemiology of the disease, and on various influencing constraints, including climatic and nutritional factors. There were also papers on studies to mitigate and manage the effects of the disease, including thinning, fungicide application, fertilisation, vegetation control, and tree breeding.

The keynote paper was given by Ian Hood (Forest Research, Rotorua), who was invited and funded to attend by the SNC Cooperative in order to outline the New Zealand experience with this disease. Indeed it became clear during the course of the workshop that there is much in common between the two regions in both the disease itself, and the way it has been and is being researched and managed. In one paper Everett Hansen (Oregon State University) addressed the question as to why the indigenous P. gaeumannii should have become a problem to Douglas fir in its native range. The answer is not fully clear, but it appears to have much to do with the establishment of Douglas fir monocultures of indeterminate seed origin in a zone of high precipitation, where the host naturally occurs only in mixed stands with other native conifer species. However, Jeff Stone (Oregon State University) revealed that a proportion of P. gaeumannii in the affected zone comprises a genetic lineage not present in other parts of the natural host range, although he did note that there is no evidence of a “new strain” being responsible for the problem. The workshop concluded with a review presentation by Will Littke (Weyerhaeuser Co.) that summed up the day’s proceedings. The workshop was followed by a 1-day field trip held within the affected Douglas fir zone near Tillamook, which provided opportunity for some intense and fruitful discussion on the problem. The meeting proved mutually beneficial, and suggested some new lines of research advantageous to New Zealand Douglas fir growers. For instance, there is clear need for a model to explain the incidence of the disease and its causative agent in this country along the lines developed in the US, to help growers assess the potential impact in their region. It is hoped that discussions held with the Oregon researchers during the course of the workshop may lead to some productive collaboration that will help fill this gap.

(Ian Hood, Forest Research)

This information is intended for general interest only. It is not intended to be a substitute for specific specialist advice on any matter and should not be relied on for that purpose. Scion will not be liable for any direct, indirect, incidental, special, consequential or exemplary damages, loss of profits, or any other intangible losses that result from using the information provided on this site.
(Scion is the trading name of the New Zealand Forest Research Institute Limited.)

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