GARDENERS are being warned four deadly diseases could be poised to devastate trees and change Lincolnshire's landscape forever.

Oaks, pines, horse chestnuts, larches, sweet chestnuts and Douglas fir are all said to be at risk – with researchers desperately trying to find a way to stop the sickness spreading.

Mike Seville, a forestry and woodland adviser for the Country Land And Business Association (CLA), said in his 35 years of working with timber he could not remember a time when trees were under so great a threat.

"At least with Dutch elm disease only one species was affected, but now we have acute oak decline in oaks, red band needle blight on Corsican pine and Scots pine and leaf miner on horse chestnuts.

"And coming from the south west is Phytophthora ramorum, the rather confusingly named sudden oak death, which is killing larch and affecting Douglas fir and sweet chestnut.

"Research has been under funded for years, so now when we are facing this potential disaster, we simply do not have the vital knowledge we need to enable us to tackle such a variety of pests and diseases.

"It is not overstating the case to say that in a very short time we could lose some of our much-loved woodlands.

"With them will go the beauty of our landscapes and a vast range of wildlife habitats."

David Bole, a development officer for the Forestry Commission in the East Midlands, said the CLA really weren't "over egging" the scale of the problem, even if some of the diseases were yet to appear in Lincolnshire.

"At the moment, the disease that is causing the most worry nationally is sudden oak death – but as far as we know it has not arrived in Lincolnshire yet.

"However, the problem is it seems to be moving very fast for a disease that affects trees and we've got to be very careful.

"With acute oak decline, as far as we know it's not here yet, but there are signs it's just to the south and I guess it's inevitably on the way.

"Red pine needle blight is on the borders of the county.

"We don't know how to control them. For sudden oak death, all we can do is cut down the affected trees and dispose of them on site, while trying to restrict the movement of people and animals in the area.

"But our officers are out and about all the time and we are keeping a very close eye on the situation."

However, Phil Porter, warden at Whisby Nature Park, said one problem for trees was already here.

He said: "There is a leaf miner moth, whose caterpillars burrow into the leaves of horse chestnuts, leaving channels beneath the surface and causing discolouration.

"Where most of a trees' leaves are affected it becomes debilitating.

"We don't have that many horse chestnuts, but most are affected and they are really being hammered."

For more information about the problems facing trees, visit www.forestry.gov.uk