How long before sexing Delawares?

[CovenantCreek]

My chicks just started hatching yesterday, so how long will I have to wait before I can tell the pullets from the cockerels?

On a different note, are they ever born with black stripes or will we be playing a game of "who's your daddy"?

 

[speckledhen]

I believe I had mine sexed by three weeks old or earlier. It's been awhile. I hatched two boys and two girls, the little vampires! The barring on the tails comes a little later; the first feathers don't have it. Here's a picture at five weeks old with the cockerels on each end.