Not sure what it is but if it is growing in a public place you shouldn't be taking cuttings and if in a private garden only with permission from the owner.

You must be real fun at parties...

I don't know how much fun she is at parties, but at least you can trust her not to steal your drink, pick your pocket, or slip you a mickey!
As for the tree, it looks like a form of Deodar cedar (Cedrus deodara)

Stealing is stealing Chilekate regardless of what it is you steal... I know of gardens that used to be open under the Yellow Book - not anymore as they were sick of visitors taking a bit of this and that plant. If you want a tree like that go and buy it!

I agree with Moongrower over this it is stealing plain and square. A close friend used to open her garden and several pretty shrubs were badly nipped. she caught one person who said he couldn't see what her problem was as it was just a 4" bit. But 10 or more little bits spoils a nice specimen.
She had propagated the shrub for sale and they were really cheap but he was too tight fisted to fork out a couple of quid.

Stealing? It's a massive tree on a piece of scrub land where I walk the dog. Not a garden, not a park - just a bit of waste land. I didn't think me plucking a shoot off it would cause so much of a stir.

Scrub land or not, it is still owned by someone. The right thing to do is to track down the owner, and get permission--in fact, ideally you should have permission to walk your dog there. If it turns out to be public land, you should contact the appropriate authorities. They might not worry about a few cuttings, since Deodar Cedar isn't a native plant, but it would be best to find out. As usual, the lessons I learned in kindergarten are best: "If it isn't yours, don't take it."
Note also that true Cedars are often reluctant to root from cuttings--grafting is usual to reproduce named forms.

Well I will own up and say that if I saw a huge tree on waste land with public access it would never occur to me that taking a small cutting would be stealing. Its not like digging up a whole plant and it would make no difference at all to the tree. Its a very different case from taking bits of this and that in someone's private garden.(A bit pointless in this case though if it wouldn't root anyway...)

Sorry I wouldn't Stera. collect 'some' seeds from a wild growing plant yes but removing a cutting from a tree 'no' as Tugb. says 'if it isn't yours don't take it'. We've had this discussion before on GoY and some folk will, others won't, it is just your nature I guess...

Wow. I am amazed at how quickly you cast aspersions. Do you really have to be so rude? You are right; stealing is indeed either part or not part of one's nature - as is being condescending, and over opinionated. Just saying...

Also, I am intrigued as to how your "If it's not yours, don't take it" policy doesn't apply to seeds. How do you justify taking those? Seems like double standards to me.

Sorry if you feel I am condescending and opinionated Chilekit. When we used to go on botany trips in our mountaineering days, sadly long behind us now, we would collect a small amount of seed from, for example, wild growing gentians. This did no harm to the plant as we left far more seed that we ever took. One day in Austria part way up a mountain we saw a spectacular gentian and agreed to take photos and collect a little seed on the way back down, when we got there the cows were just finishing the last of the flowers off, having eaten every last stalk! Collecting wild grown seed is an accepted practice and enables plants that have died out to be reintroduced from the wild.

Sadly, many native Arizona wildflowers, cacti, and shrubs have been collected nearly to extinction, both in seeds and in plants, by well meaning folks from other climates. It is now illegal to collect seeds here, unless you have a permit from the State government.

Collecting seed now has all sort of rules and regulations attached Tugb. including CITES and various permits that have t one obtained - all for the reasons you have mentioned.