What timber to use for top of handrail

Hey all.
The posts are in for the handrails. The balustrade should be here tomorrow. Im unsure what timber I use for the top of the handrail. I have Merbau deckboards, Treated cypress for the posts, 100x100 at 1m in length. They have been sanded down and planed the corners off, and they actually look quite nice and the grain will be nice once oiled.

I have no idea what timber to use for the top of the handrail. It would have to be 100xsomething to cover the post.
Also, how do I attach it to the post, just nail it from the top into the post? Will this split the post?

Your opinons and advice would be greatley apprecaited as I have no idea what type of timber to use.

cheers.

I used treated pine, which I routed a groove into to receive the 42x42 balusters. I have attached a picture of the handrail and balusters, well, the best picture I have anyway.

I think the top-rail is 90 x 35, I can measure it if you want...

The whole thing went up pretty quickly, once I had the lot painted. It is a damn site easier to paint the balusters before they go up, believe me! I leant that on the first deck I did!

As to attaching to the posts, I used angle-brackets, as well as two screws.

If you want to know the entire procedure I used, I can post in more detail.

Cheers

Jayson.

Angle brackets...Hmm Didnt think of that.
The span between my posts are 2.3m, Alot of guys here said I'll have to put a post inbetween as the timber may sag in the middle. I want to avoid doing this but I dont think i'll get away with it. I'll be using the stainless steel cable for baulsters so painting is not an issue.

Thanks for the info splenux. Is each peice of timber to the post a seperate piece or did you go one full length of timber?
Cheers.

From post to post is one piece of timber. The span you see there is about 2.3 metres, you just need to put a couple of 'chocks' underneith the bottom rail. I think you would need a fairly chunky peice of timber to span 2.3 metres without the supports in place. The Alan Staines manual has heaps of info in it for hand-rails, I recomend you look it up.