Austrians demonstrate benefits of long-term forest research

In 1967, the International Union of Forest Research Organisations (IUFRO) in Munich agreed a research programme to assess the performance of Norway spruce in 14 European countries, including Ireland. A series of experiments was established in 1969 and 1970 to address aspects of thinning regimes in Norway spruce stands throughout Europe.

Norway spruce was chosen as it has a widespread distribution in Europe. It is a major commercial species from Scandinavia in the north, stretching east to Russia and south to the northern border of Greece. It is also native to central Europe and is widely planted as an introduced species in western Europe including Ireland.

This project underscores the importance of long-term research as advocated by Thomas Ledermann, research forester with the Austrian Research Centre for Forests (BFW) in conversation with members of the Society of Irish Foresters during a study tour to lower Austria last October.

The BFW holds the legal status of an institution under public law. It consists of six specialist institutions:

BFW also has two forest training centres, a library and numerous internal service centres.

Continuity

It provides research continuity and as a result, the Austrian plots (pictured below), located less than 1km east of the abandoned village of Döllersheim, are still intact. Researchers continue to collect data on their performance, unlike the Irish plots which were harvested prior to 2006,

Data collected in 2012 when the stand was 43 years old, suggested an estimated yield class (YC) of 20-22m3/ha/annum with heights (of mean basal area trees) from 25m to 31m. These yields are excellent for Norway spruce (the average YC for Ireland is 16) especially as the growing season in lower Austria is shorter than Ireland and rainfall is lower – 699mm compared with over 1,000mm in Ireland. However, the soil type – a Cambisol – is regarded as heavy but classed as agricultural land.

The Austrian experiment took on an added interest due to the presence of Dr Gerhardt Gallagher who played a key role in establishing the Irish experiment in Granard, Co Longford. He was a research forester with the research branch of the then Forestry Division in Ireland, which was transferred to Coillte in 1989 and later disbanded.

He supported Dr Peter Abetz, project coordinator, who wished to include the Eastern Bloc countries in the project. Dr Gallagher believed in wide-scale European involvement, partly due to his background – his grandmother, Margarethe Gerhardt, was a well-known painter and etcher from Warnemunde in former East Germany. It should be remembered that the project was proposed five years before Ireland joined the EU and 22 years before the collapse of communism in eastern Europe.

Interesting comparisons were drawn between the Irish experiment and similar European trials during the collection of data in 2005. The Irish stand had an 18 to 20 YC with an original stocking of 4,536/ha compared with YC 20 to 22 in Austria where the original stocking was 5,200-6,000/ha. The various trials had a number of silvicultural regimes including early, late and no thinning.

It is likely that the Austrian stand will be managed until it reaches its full YC 20-22 potential. It will reach maximum annual increment (MAI) at age 65 in 2034. Irish foresters clearfell Norway spruce crops at 70% of age of MAI or at 45 years for YC20.

Long-term research

To maximise a forest’s contribution to climate change mitigation, it has been suggested that trees should be allowed grow to age of MAI and beyond. This would require a change in forest management practice and possible long-term research to provide information on the consequences of extended forest rotations.

Extending the age of clearfells beyond current so-called financial rotations would postpone the date of lucrative clearfell revenue but would provide income from thinnings when the crop is producing maximum yield. There are of course other implications in longer rotations including windthrow vulnerability and challenges for sawmills to process larger log sizes.

Sections of the Granard stand suffered some windblow and thus may have been clearfelled to avoid further wind damage. Dr Gallagher and Ted Lynch, recently retired from Coillte, authored a number of papers on the project but the valuable information that could have been garnered if the research trial continued is now lost forever.

The Norway spruce experiment as managed in Austria, underlines the value of long-term research as emphasised by both Thomas Ledermann and Gerhardt Gallagher when they discussed the transnational Norway spruce project with other foresters during the study tour.

Long-term forestry research provides information not only on yield but also on disease vulnerability, forest soils and crop stability, as well as providing a time series to record and monitor unforeseen effects.

Despite repeated calls by the Society of Irish Foresters, Ireland does not have a forest research institute with a budget to fund long-term research.

Research institute

Instead, funding is provided by the Department of Agriculture, Food and the Marine for short-term contract based research. The Council for Forest Research and Development (COFORD) advises the Department on research and development issues including projects worthy of funding. This body is doing admirable work but the Society of Irish Foresters believes that forestry needs a permanent centre for forest research. “This would provide long-term trials, which would be retained in State ownership,” said Dr Gallagher, co-author of the SIF policy position paper on forestry research.

“Ireland’s ability to respond to environmental crises related to climate change and international disease spread or to capitalise on the material, financial and social benefits generated by forests, is compromised by the lack of a research centre,” he said.

Pat O’Sullivan, technical director, Society of Irish Foresters, stressed the need for a forest research institute. “The society calls for a long-term commitment by the state to research and development,” he said. “Despite excellent work by COFORD, organisational changes in recent years have reduced the scientific and technical support necessary to protect and further develop the forestry resource. We have seen evidence of the benefits of long-term forest research during our study tours to countries with strong forest cultures, which was reinforced during our recent visit to Austria.”