Need to repair a timber cowshed. Some will be at ground level i.e. close to the muck, although shouldn't be submerged. From what I have read, larch or Douglas fir is what I should be looking for. Is this correct? I guess I'm not going to get this from the local jewsons, in 4'x5' 6m lengths, so while I'm here, are there any suggestions for good timber merchants that can supply in the south Midlands?