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Argyll Pilot Project - Conclusions Report:


Methods - accuracy & ease of use

Level 1
The accuracy of this remote survey was tested by the field survey work at Level 2 which confirmed the woodlands to be Semi-Natural in over 96% of cases.
The collection of data is straight forward provided training and equipment is provided.

Level 2
The accuracy of this new 'walkabout' field survey method was broadly assessed by examining the consistency of the results from a number of test woods each of which was surveyed by all the survey teams.

A comparison of the survey results from each team showed that there was a high level of consistency between the results recorded by each team across all the woods. At a general level this suggests that the overall accuracy of this level of survey is likely to be high.

Whilst all the survey teams found the standardised survey method straight forward to use, comments from the teams and others who have since used the Level 2 survey method, combined with analysis of the results, indicated that:

  • Standardised 1:10,000 scale maps are the best for recording supporting information and making target notes to support the survey cards

  • Minor modifications to the survey forms are required to give greater consistency between tables on the forms designed to record similar information (e.g. 'habitats within the wood' and 'surrounding land-use'). Also a more logical sequence of the tables on 'Woodland Survey Card I - general Information' is necessary to reduce the time needed to complete the card.

  • For woods where a Level 3 timber survey is planned, a complete Level 2 survey is best undertaken at the same time, rather than before.

Level 3
A detailed Level 3 timber survey was carried out on a sample of 62 woods comprising 84 compartments and 829 survey plots in order to:
  • Provide a broad validation of the Level 2 timber survey method.

  • Investigate the suitability of the Forestry Commission's conventional hardwood timber measurement method for assessing timber volume in variable semi-natural woods.

The Level 3 survey information suggested that the Level 2 timber assessment was adequate to identify the timber management opportunities at each wood and also gives a good broad indication of the potential for management of the overall hardwood resource in Argyll, which is what it was designed to do. However, the Level 3 work also suggested that the stocking and girth categories described on the Level 2 survey forms require minor modification.

The Forestry Commission method as described in FC Booklet 49 (B5) suggests that, "as a rough guide, the expected accuracy" of this method for volume determination is +/- 13.45%. In this survey, a comparison of the timber volumes for 6 hardwood species growing in semi-natural stands using the FC method and the volumes obtained by a professional hardwood timber buyer was made. The results of this comparison showed that the volumes obtained by each method across all 6 species was +/- 10%.

The limited trial of this simple method of determining hardwood timber volume in semi-natural stands showed promising preliminary results. However, further trials in other parts of the country will be necessary to validate these results.

Additionally, a separate small trial to assess a new simple method to determine the quality of standing oak timber was carried out. The results of this method when compared to those obtained by an experienced hardwood timber buyer showed promising preliminary results. Again however, further work is required to confirm this trial.

Presentation Methods

A questionnaire was sent to all owners / agents of woods surveyed, and to other likely end users of the survey information in order to identify the preferred method of presentation of the survey results. 261 questionnaires were issued and 48 (18.4%) were returned.

76% (37) replies were from woodland owners, 8% (4) from forest management companies, 10% (5) from National Government agencies and 2% (1) from each of Local Enterprise Company, representative body and woodland partner.
73% of the respondents requested the survey information to be provided on an individual wood basis whilst 17% requested the information summarised by the whole of Argyll.

When asked in which format they wished the data presented, 69% (33) of respondents preferred electronic format, although 81% (39) of respondents stated that they had access to a computer. 62% (30) of respondents wished to see the information made available on a web site on the Internet.

Only 19 respondents (40%) replied to the question "how do you feel about data being freely available to the general public?" Of these 14 were happy for the data to be freely available. Interestingly, when asked whether individual woodland ownership details should be made available, 80% (38) of respondents agreed that this information should be made available.

The conservation and forestry agencies when consulted expressed a desire for the information to be provided in electronic format suitable for use within a Geographical Information System (GIS).

Based on these responses, the information was provided in the following formats:
    1. A web site on the Internet
    2. A web site on a CD ROM
    3. A web site and a GIS project on a CD ROM

How useful are the new survey methods and results to the target end-users?

The Level 2 survey method is now in wide use by the Forestry Commission in Scotland as a standardised way of gathering base-line information on existing semi-natural woods which are under management through the Woodland Grant Scheme (WGS).

The web site has been demonstrated to key staff in the Forestry Commission and there is considerable interest in the data and also in the application of the survey methods to other areas of Scotland.

The usefulness of the Argyll survey results will be assessed by a questionnaire to SNH, the Forestry Commission and the Argyll and Bute Council in late 2001. Over the longer term, the usefulness of the survey methods will be indicated by the number of times it is used in other parts of the country over the next 10 years.

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