once had 2 pups get to ground and work at 5 months, many a pup will start at 6-7 months I've had a few accidents over the years and its far to young, , 10-12 months still to young i think but i have dug to them in easy places at that age and then held them back a few more months , when a young terrier starts and all that breeding shines throw and the pup works like a veteran people often forget there still pups , many start well at 12 months and walk off by 18 months and any terrier under 18 months is still a pup IMO the human in this partnership is supposed to be the intelligent one, and kno