| Name | Structure/ Category | Description |
|---|---|---|
| Indehiscent | Not splitting or forming an opening at maturity, the contents being released for dispersal only after decay, digestion or erosion of the structure, as certain fruits, such as achenes and berries, that retain their seeds when ripe. ( | |
| Indeterminate inflorescence | An inflorescence in which the lowermost or outermost flower opens first, with the main axis often elongating as the flowers develop, as in racemes. | |
| Indusium | The sorus (or spore-bearing structure) of some ferns is partially covered by a pale membrane that is called an 'indusium.' The indusium may fade away as the fertile leaf of a fern matures. The plural form of this term is 'indusia.' | |
| Inferior | [Ovaries] {position} | With the ovary wholly enclosed by and fused to a floral cup, the whorl of sepals and petals (perianth) and/or stamens (androecium) thus appearing to arise from the top of the ovary. |
| Inflorescence | 1) The mode or pattern of flower bearing; the arrangement of flowers on the floral axis. 2) A basic unit of the flower-producing portion of a plant, composed of one or more flowers and any supporting stalks and appendages (e.g. bracts, involucres, etc.); a flower cluster. | |
| Infrapetiolar | [Buds] {position} | Axillary and surrounded by the base of the leaf stalk or petiole. |
| Insertion | The location of points of attachment of a structure (e.g., a leaf) to some dissimilar bearing structure. | |
| Internode | The portion of a stem between two nodes, i.e. the part where leaves and/or branches do not arise. | |
| Involucre | A whorl of bracts subtending a flower or flower cluster. | |
| Involute | [Leaf margins, Leaflet margins] {vertical disposition} | With margins rolled inward, toward the upper side. (Compare with plane and revolute.) |
