A botanical reference guide of morphological terms, plant structures, propagation techniques, and campus flora definitions.
Explore terms organized by botanical structure, morphology, and arboricultural concepts.
Pinnate Having parts arranged like a feather, symmetrically on either side of a central rib - often used to describe compound leaves. Did you know? Ash, walnut, hickory, and rose leaves are pinnate, with leaflets arranged along a central stalk.
Pith The spongelike substance in the center of a stem. This feature helps describe plant support, storage, water movement, or vegetative spread.
Pleaching A formal technique for training trees or shrubs in which the branches are interwoven and plaited together to form a hedge or arbor
Plica A plait or fold. This feature helps describe plant form, function, or identification.
Plumose Like a feather. This feature helps describe plant form, function, or identification.
Pollarding A pruning technique in which the main limbs of a tree are cut back each year to very short stubs
Polymorphic Occurring in several different forms. This term helps record, compare, or interpret plant and site information.
Pome A type of fleshy fruit. This feature is connected to how seeds are protected, nourished, or moved away from the parent plant. Did you know? Apples and pears are pomes. The edible flesh forms from tissue around the ovary, not only from the ovary wall.
Prickle A sharp outgrowth of the epidermis or bark, different from a thorn or spine. Did you know? Rose “thorns” are prickles, which arise from the outer stem tissue rather than being modified branches.
Procumbent Trailing or lying flat on the ground, but not rooting
The Purdue Arboretum is a collaboration between the Department of Horticulture and Landscape Architecture and Administrative Operations