Unused land in Bristol should be snatched from the wealthy to tackle the region's allotment crisis, the Government will be told today.

The New Local Government Network (NLGN) says tax incentives should be offered to owners in return for use of part of their estate but, if a voluntary system does not work, they should be forced to give up the much-need plots.

That could be done by setting up a Large Private Estates Commission, which would have the power to temporarily transfer unused plots of private land to the local community for agricultural use. In the Can you Dig it? Meeting Community Demand for Allotments report out today, the think tank states that while the number of allotments has dramatically dropped from 1.4 million in the 1940s to 200,000 now, there has been a recent increase in demand. Across Bristol there are 1,387 plots but 1,069 people on waiting lists. Bath and North East Somerset has 1,100 places and 450 waiting, while South Gloucestershire has 296 plots and 145 gardeners waiting. No information was available for North Somerset.

Chris Leslie, director of the NLGN, said: "Our reforms would see much more unused and unfunctional brownfield land developed into a much more picturesque landscape of working allotments. Furthermore, with one per cent of landowners owning 70 per cent of land in the UK, we would like to see the Government encourage them to share a small portion of it with people in their local communities, particularly those who do not have access to their own garden."

The Royal Family owns 677,000 acres of land nationally and although some of it is already used for farming, NLGN believes more could be used for the benefit of the community.

More than 3,500 hectares of brownfield land is currently unused and could also be transformed, the group says.

And local authorities across the country should follow Bristol's lead, the report said, praising the council for its pioneering allotment schemes which included offering discounts to certain low-income groups and compost initiatives.

The report states: "Bristol City Council has combined its allotment services with waste. In the autumn, the council offers leaves to the allotments with vehicular access, for the purpose of compost rather than taking them to landfill, benefiting both the allotment tenants and the council."