what is this a weed or asparagus

We are very new to this .We have lots of shoots coming up which are about a centimetre in diameter. Every 5 centimetres or so it appears to burst up similar to a telescope. The head is like a cone almost the same size up to the tip there are small seeds (2 millimetres wide).almost like a corn on the cob. I have not dug down to see what the roots are like. Any suggestions do we eat it or exterminate it. Thanks

Is it possible to take a pic, or maybe on your next trip to the supermarket have a look at asparagus.

Or failing that google asparagus pics that should be fairly conclusive 

I,d be tempted to go with marestail/horsetail too. I thought the exact
same thing when i got my plot not so long ago.
Its about the right time for it to be popping up too, I know this cos its all over my plot at the mo.
Dig out what you can then forget about it because you will never beat it, just learn to live with it
and deal with it as and when it pops up.
Weedkiller/glyphosate has very little effect on it unless you crush it first to get past the waxy coating.
Best of luck!

The section like telescopes bit is consistent with Mare's Tail, but yes, 1cm is rather thick.

Does it look like this?

http://www.flickr.com/photos/greenthumb/8921818/

If so, it's Mare's Tail.