HC Deb 26 October 1977 vol 936 cc833-6W
Mr. Whitehead

asked the Minister of Agriculture, Fisheries and Food whether the Forestry Commission is conducting research into the development of elms resistant to Dutch elm disease; and what results have so far emerged from such research.

Mr. Strang:

The Forestry Commission is conducting no research of its own on the development of elms resistant to Dutch elm disease. It is instead supporting the long established elm breeding programme being undertaken at Maganingen in the Netherlands. This research is essentially long term but the results indicate that elms can be developed with resistance to the non-aggressive strain of the disease but not so far to the aggressive strain.

Research studies in North America however demonstrate that vigorous sanitation felling campaigns in selected urban areas have been successful in slowing down the progress of the disease.

Mr. Whitehead

asked the Minister of Agriculture, Fisheries and Food, what fixed in sterling. The net cost to the importer is the common levy less the accession compensatory amount and less the monetary compensatory amount.

estimate he has made of the amount of timber, which would otherwise have been used, which has been lost in consequence of the present outbreak of Dutch elm disease.

Mr. Strang:

Such an estimate is not practicable. With the advice of the Elm Marketing Group set up by the Forestry Commission and the continuing cooperation of the timber trade, a more diverse use is being made of elm from this source and at present the demand for good quality elm exceeds the supply. If there had been no epidemic, many of the elms which have had to be felled would have been left standing as their purpose was to provide amenity rather than timber.

Mr. Whitehead

asked the Minister of Agriculture, Fisheries and Food how severe are the fresh outbreaks of Dutch elm disease in 1977 in Great Britain; and which countries are now classified as lightly or heavily affected.

Mr. Strang:

The effect of fresh outbreaks this year will not be fully known until the end of November when the Forestry Commission completes its assessment. It is clear however that the disease continues to spread.

The counties which are at present classified as heavily affected are listed in the schedule to the Dutch Elm Disease (Restriction on Movement of Elms) Order 1977, S.I., 1977 No. 1075, which came into force on 2nd August 1977. In broad terms counties north of a line from the Mersey to the Humber, and in West Wales, are classified as "lightly affected". The remainder are classified as heavily infected.

Mr. Whitehead

asked the Minister of Agriculture, Fisheries and Food whether the Forestry Commission has conducted any research into the ecological impact of a substantial reduction in, or the total elimination of, the elm population in a particular area; and if he will make a statement.

Mr. Strang:

The Forestry Commission has not undertaken any research into the ecological impact of the reduction of the elm population.

Mr. Whitehead

asked the Minister of Agriculture, Fisheries and Food what was the total elm population of Derbyshire before the outbreak of the present epidemic of Dutch elm disease; how many have been infected with the disease; how many of these have been felled: and how many have been inoculated against the disease with fungicide or insecticide.

Mr. Strang:

Forestry Commission surveys have been conducted on a sample basis and detailed information in the form requested on individual areas could not be compiled except at disproportionate costs. Information on the number of trees treated with insecticides and fungicides is not available as this work is done by contractors for individual private owners.

Mr. Whitehead

asked the Minister of Agriculture, Fisheries and Food what advice his Department gives on the use of insecticides and fungicides, respectively, for the prevention of Dutch elm disease; and how many trees were so treated in 1973, 1974, 1975 and 1976, respectively.

Mr. Strang:

The Forestry Commission does not recommend the use of insecti- cides for the prevention of Dutch elm disease as it is generally unsatisfactory for biological and environmental reasons. The injection of fungicides is still to a large degree an experimental and costly process requiring the treatment to be repeated annually. It would be uneconomic to do this on a large scale but it has proved relatively effective for young and vigorous trees of particular amenity value. Information on the number of trees treated with insecticides and fungicides is not available as this work is done by contractors for individual private owners.

Mr. Whitehead

asked the Minister of Agriculture, Fisheries and Food what is his estimate of the total number of elm trees (a) infected with Dutch elm disease in 1977, (b) dead since 1976, but still unfelled, (c) dead since 1975, but still unfelled, (d) dead since 1974, but still unfelled, and (e) dead since 1973, but still unfelled, respectively.

Mr. Strang:

This information is not available in the form requested. The Forestry Commission's estimate of the current situation will be published in November after the information available during the current year has been collected and assessed.