Here is a little teaser. I try to cut the logest briars I can. To take the thorns off, you can use a knife, or do what I did. Put on a heavy leather glove, grip the briar and slide your hand down it. It will leave little humps where the thorns are.
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Once that is done use a small knife to split the stalk. Its easier to split from the big end and work the blade down to the tip.
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