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\section{Air-Layering}

Air-layering is a variation on layering.
To reproduce an herb by air-layering,
score one branch of the plant's stem
with a knife.  
Tie a plastic bag with
soil and water tightly above the score
line.

Now let's take a look at some individual
herbs in more detail.  Let's start with
sweet basil. Sweet basil is a 2-foot to
3-foot-tall annual with oval-shaped
leaves 2--3 inches long. When
its leaves are brushed, it gives off a
sweet odor.

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