What is the correct definition of leaf cuttings?

Leaf cuttings refer specifically to sections of a plant's leaf used for propagation, and in this context, the definition that states a leaf cut with a petiole cut to less than half an inch is accurate. The petiole is the stalk that connects the leaf blade to the stem, and in leaf cuttings, having a shorter petiole is beneficial because it reduces the risk of rot and allows for better rooting of the cutting in the growth media. This specific length encourages the cutting to focus energy on developing roots rather than maintaining a longer petiole, which can retain moisture and encourage decay.

In propagation practices, leaf cuttings are usually employed for certain plant species that are better suited to reproduce this way, and proper handling and dimensions of the petiole are crucial to successful rooting. The other choices do not align with conventional practices; a longer petiole or a leaf without one does not typically yield successful rooting results, nor does just avoiding visible damage define a leaf cutting's suitability for propagation.