This can be found at
http://www.communities.gov.uk/publications/planningandbuilding/hedgehe ight
The full report (BRE client report 203703) can be downloaded free at http://www.communities.gov.uk/documents/planningandbuilding/pdf/highhe dgesdaylight.pdf
BRE does NOT have any copies to send out and cannot offer advice on individual problem trees or hedges.
BRE’s 2004 review of the regulations is at:
http://www.communities.gov.uk/documents/planningandbuilding/pdf/review guidancehedge.pdf
DCLG has a guidance leaflet for householders called Over the Garden Hedge, see
http://www.communities.gov.uk/documents/planningandbuilding/pdf/overga rdenhedge.pdf
If you have trouble finding the above pdf documents, see http://www.communities.gov.uk/ and search for hedges.