Arboretum Botanical Glossary

Hilum A scar indicating the previous point of attachment of a seed or ovary Did you know? The hilum is easy to see on a bean seed as the small scar where the seed was attached to the pod.

Hyaline Thin, membranous, and transparent or translucent. This feature helps describe plant form, function, or identification.

Hybrid A plant resulting by combining the characteristics of one type of plant with another through cross-pollination. This can occur naturally or deliberately through human action. Did you know? Grapefruit is a natural hybrid between pomelo and sweet orange.

Hygrophanous Having the characteristic of changing color upon drying. This feature helps describe mushroom structure, spore production, or fungal identification.

Hypanthium A cup-shaped extension of the floral axis, commonly surrounding or enclosing the pistils. Did you know? Rose hips form from an enlarged hypanthium and are rich in vitamin C.

Imbricate Overlapping like roof shingles. This feature helps describe plant form, function, or identification. Did you know? Pine cone scales overlap imbricately like shingles, protecting seeds until the cone opens.

Impressed Located below the surface. This feature helps describe plant form, function, or identification.

Incised Cut by sharp and irregular incisions around the edge. This feature helps describe plant form, function, or identification.

Indurate Hardened. This feature helps describe plant form, function, or identification.

Inferior Beneath, below. This feature helps describe plant form, function, or identification. Did you know? Apples develop from flowers with inferior ovaries; the fleshy apple includes tissue around the ovary as well as the ovary itself.