Starnge behaviour out walking

As you know where we live is on the outskirts of the city, so it is a lot of fields, woods, etc. Stables and farm and such. And this is where the dogs go for walkies, we take them round twice a day.
Now they are sort of working terriers, mostly ratters and such, but havent gone on a propers day work for about a month now, apart from the odd rat caught at my aunts stables.
Anyway Florrie, my westie cross dandie dinmont, is 5 and a half months, and when we go out on wal;sk, she very rarely goes for a 'number two', she will pee and such, but nothing else, any ideas why?

May be she just finds things too interesting to bother to go or may be she likes to do it in the safety of her own back yard, either way it saves you from having to pick up and then try to find somewhere to put the bag, would encourage the behaviour if I were your.

Until Teagan was about 7/8 months old, she wouldn't poo or pee outside the garden!!
I wouldn't worry

I prefer it if my dogs do a no.2 in my garden its easier to clean up and I can just disinfect my garden

Dogs are creatures of habit. Often they prefer to eliminate in a specific area. My own dogs are trained to pee and poo on command, but I know they find that difficult/uncomfortable when on unfamiliar territory so I never insist unless I know they really, really, must need to go.

same with tyson he will only go in the garden he wont even pee outsode the safety of out garden i bought a pee post and he goes there mostly . i always clean up straight away afters hes been poo , i wouldnt worry about it . its perfectly normal .

Loki WON'T go in the garden if he can help it - even though he was encouraged to from day one. He seems to like to keep it as far away from home as possible. Shame he doesn't feel the same way about pee though - my garden is like a desert