No, it's not normal. This is a garden sorely neglected. It needs a little love.

That is odd - I was expecting to see equisetum, which can grow like asparagus, but it does indeed seem to be an asparagus spear. What's in front of it, in the ground? The most likely explanation is that there was once an asparagus bed in front of the cherry tree, which is either now removed or not functioning, but some of the root had spread close to the cherry and could not/cannot be removed and is still producing growth. No evidence of ferny leaf growth along with it, but that may arrive later.

You might as well remove the stem by cutting it off at the base, if only to inspect it more thoroughly by cutting into it, to confirm it is actually asparagus. Asparagus are cropped at slightly below this length anyway in a functioning asparagus bed, so if there is a root there, it will produce more (and leaves) over time.

Are there a few more of these stems in the grass on the other side of the tree?

Thanks for the replies, most appreciated. The garden has thrown up some random and good surprises-wild garlic, fox gloves in droves, roses, etc. Anyway, I realise it needs some tlc and I'm planning to help make it more useable.

To answer the questions asked there don't appear to be any other stalks or leaves from the asparagus plant/root. Underneath the cherry tree there is wild garlic, a peony, and then it's either paths or lawn. I'm doubting that's where the previous owner would have set up an asparagus bed, but you never know. I think I will cut the stem and then keep an eye on the area to see if any other stalks appear.

Thanks again