It should have a thin woody layer and plenty of pith.

If these conditions are fulfilled the species matters little.

I should pass in review all the semi-ligneous plants of the country were I to catalogue the various supports which are utilised by the gravid female.
Its chosen twig never lies along the ground; it is always in a more or less vertical position.

It is usually growing in its natural position, but is sometimes detached; in the latter case it will by chance have fallen so that it retains its upright position.

The insect prefers a long, smooth, regular twig which can receive the whole of its eggs.