If you are buying an older property then it will more than likely have lath and plaster ceilings and walls. If the property is Listed, then this will almost certainly dictate the type of laths you use for any repair.
Grade II Listing is usually straight forward and wooden laths that have been machine cut can be used- made from Baltic Pine, these are known as Restoration laths.
Grade II* and/or Grade I Listings will more often than not need to be repaired with hand riven laths- which are exactly that- laths cut by hand and these can be made from oak, pine or chestnut.
Does it matter which you use? In a nutshell, yes. Where there is a Listed Building there is a duty to repair it in the correct manner so that it complies with the listing requirements. The Listings Officer will insist on inspecting the work to ensure that the correct laths are used.
Get it wrong and it's no laughing matter.....
Hefty fines await those who digress- and the owner of the property will suddenly find themselves in deep water. It's no laughing matter when you get fined thousands of pounds for getting it wrong, plus then having to have the contractor come back and put it all right. Best not to go there- get yourself a contractor who knows the rules and how to restore buildings in the correct manner.
P.S. A useful tip- when repairing laths, don't throw out the old ones- many can be salvaged by screwing them back into situ. Avoid the use of nails as hammering can shake the existing mortar out from the laths and cause more damage.