Differences inside the stalk
1. On a transverse section of the stalk
The differences that can be macroscopically detected between the two species on a transverse section of the stalk are the following:
- the section of a hemp stalk is comparable to that of a cogged gear except at the base where the section is more regular and rounded. There is no pith, while the walls of the central channel have the typical whitish colour;
- the kenaf stalk always has a regular, rounded section. There is pith all along the stalk, progressively decreasing towards the top. The lumen of the central channel, as in the case of hemp, decreases at the base of the stalk, but - on the contrary to hemp - there is always pith.
2. On a longitudinal section of the stalk
There are the following differences:
- hemp has constrictions in the central channel in correspondence with the nodes, while kenaf does not have this characteristic, but is, more or less, continuous;
- more than in the transverse section, the longitudinal section of a hemp stalk shows the bright white colour of the walls of the central channel. Whereas in the case of kenaf they are greenish and sometimes there are also fibres similar to the textile fibres that extend longitudinally;
- the hemp stem is very rich in wax, while the kenaf stem contains a minimum quantity of it;
- the central channel of kenaf has pith, whereas there is none in hemp.