Much leftover land is the result of boundaries being left indistinct. Other areas have been cut off from the main estate by road improvements. Some are plots bought to build a house by someone who may have emigrated or died without issue, leaving no record of the purchase. Many used to be parts of commons which have been enclosed and developed, leaving small portions ownerless.
Many of these plots are the result of 'champagne auctions' held in the early 1920s, when there was a rush to build homes 'fit for heroes'. Agricultural land was cheap and planning regulations almost non-existent. A new phenomenon, mass car-ownership, brought your place in the country within easy reach of the city. For land speculators it was the ideal opportunity to make a quick buck.
London wide boys would drive into the country, buy a couple of fields from a farmer, divide them up into building lots - often tiny - put up a marquee and auction them off. Never mind that the lots were not big enough to put a decent house on, or that water, electricity or drains were completely absent. Promoters made sure that the one commodity that oozed from every pore on the night of the sale was champagne, and many bought ridiculous, handkerchief-sized parcels of land. Eventually, some buyers amassed enough plots to build a house on, and the area developed piecemeal. This building chaos paved the way for planning legislation in the 1930s.
There is just such an area outside the village of Windlesham, in Surrey. It was sold in tiny lots, of about 1 1/4 sq yds, and many are now of unknown ownership. Several have been fenced in and occupied by neighbours to enlarge gardens. Some form small, unofficial parks. A couple of plots in the middle of one of these parklets came up for auction recently, almost an afterthought to the main sale of land belonging to a local farmer, known as Dudley 'Dynamite' Glanfield because of his resolute - but fruitless - opposition to plans to run the National Grid, several oil and gas pipelines and the M3 across his land. No one knew how Glanfield had acquired the plots, but to prevent them falling into the hands of developers, residents got together and bought them for pounds 5,500.
Land without an apparent owner is a strong temptation to neighbours with expansionist tendencies, and it is perfectly legal to take over abandoned land and occupy it. When Una and Peter White bought a new end-of-terrace house on the outskirts of Gosport, Hampshire, 20 years ago, it had an adjoining 10ft-wide strip of land, fenced off to one side, next to an ancient church path. The first owner had occupied it to provide somewhere to park his boat, having secured an indemnity from the developer of the house just in case the land belonged to someone after all. The Whites inherited the indemnity on buying the house.
'The solicitor showed us the area on the plan, waved the document at us and said that it didn't make any difference, so we bought it,' says Peter. Twenty years on, the Whites have absolute title to the land and have built a new garage on it.
Jennifer Rickard, of the solicitors Nabarro Nathanson, explains that the onus is on a landholder to enforce his rights to land. Abandoned land is available land, according to the law. 'Under the Limitations Act of 1980, if a landowner wants to bring an action to recover land they have 12 years to do it,' she says. The key is a concept called 'adverse possession', which means taking control of land in opposition to the rights of the owner. If the owner takes no action to prevent the invasion, ownership can pass to the invader. 'For a person to have adverse possession, the real owner has to be dispossessed in some way,' Rickard explains. 'To take adverse possession you also have to make an act of possession, such as fencing off the land or putting down crazy paving, training trees and cutting the grass.
'It has to be without the permission of the true owner - renting the place and then refusing to pay the rent is not adverse possession.'
So if you have a plot of land next door that does not appear to be wanted by anybody, how do you incorporate it into your own garden? Let's assume that enquiries at the Land Registry have failed to identify the owner and that no one seems to have any interest in the property. The best thing to do is simply to go in openly with a pile of fence-panels and fence it off, Rickard says. She also advises taking photographs of yourself nailing up fence posts holding a copy of the day's Independent as proof of the date of occupation. If an enraged owner turns up with evidence of ownership, you will have to forget your territorial ambitions. If the initial occupation is successful, over the next 12 years you can become gradually more confident, but you must continue tending the plot, as this is how you establish rights over it.
If the house is sold before the 12 years are up, the accumulated years pass to the new owners. To make sure that they can lay legal claim to the plot as soon as possible, Rickard advises getting the vendors to make a statutory declaration (a sworn statement before a Commissioner for Oaths) to the effect that the property was fenced in without the owners' permission on such-and-such a date. If, however, the true owner happens to be the Crown, you have to sit it out for 30 years before the land becomes yours.