Request for information – FOI14545
Thank you for your email 29 April 2015 requesting the following information:
If possible I'd like to know the last date the "tree line" or woodland area was surveyed (or better still a history of changes) – from www.ordnancesurvey.co.uk/business-and-government/help-and-support/products/tile-selector.html. I can see the Date of Last Change was xxxxxx but it only indicates the number of cumulative changes, not what's actually changed.
Also, to what accuracy is woodland mapped at 1:1250? Is it the trunks that are mapped on the ground or the tree crowns from aerial photography? I appreciate it's an impossible task to map every tree accurately at this scale but what are the guidelines you work to (or worked to in xxxxx)?
I can confirm that Ordnance Survey does not hold the information requested. However, under our duty to provide advice and assistance as stipulated in Section 16 of the FOIA, we can provide the following explanation which may assist you in this matter.
Tree lines or edges/limits of woodland are not exactly defined. They are sketched graphically following the approximate line of the trunks. This is done both on the ground and from aerial photography.
Please find attached two screen shots from our old LandLine data, one from xxxx and one from xxxx. The xxxx map shows that the edge of the trees is in the same position as it is now. The xxxx extract shows the houses first appearing in our mapping (less the fences). These are the major changes between xxxx and the current mapping. I can’t say when this edge or limit line was first surveyed as we do not have that information; xxxx is as far back as we can go.
I hope the above is useful to you.
Your enquiry has been processed according to the Freedom of Information Act (FOIA) 2000. If you are unhappy with our response, you may request an internal review with our Internal review Officer, by contacting them using the following details:
FOI Internal Review Officer
Customer Service Centre
Please include the reference number above in any correspondence. You may request an internal review where you believe Ordnance Survey has:
- Failed to respond to your request within the stipulated time limit (normally 20 working days)
- Failed to inform you whether or not we hold the information requested
- Failed to provide the information requested
- Failed to explain the reasons for refusing a request
- Failed to correctly apply an exemption or exception
The FOI internal Review Officer will not have been involved in the original decision. They will conduct an independent internal review and will normally inform you of the outcome of the review within 20 working days. In exceptional circumstances, this may be extended to 40 working days, in line with the guidance from the Information Commissioner.
The FOI Internal Review Officer will either: uphold the original decision, provide an additional explanation of the exemption/s applied or will release further information, if it is considered appropriate to do so.
Appeal to the Information Commissioner’s Office (ICO)
If, following the outcome of the internal review, you remain unhappy with Ordnance Survey’s response, you may raise an appeal with the Information Commissioner’s Office at:
The Case Reception unit
Customer Service Team
The Information Commissioner’s Office
Telephone Helpline: 0303 123 1113 or 01625 545745 for advice, Monday to Friday.