The seeds of conifers or cone-bearing plants (pines, spruces, firs, etc.) are borne exposed on the surface of the cone scales (hence Gymnosperm, "naked seed") and not enclosed in an ovary, as in the case of Angiosperms ("covered seeds"). If a fruit be defined as a ripened ovary, there is, therefore, no such thing as a true fruit in a gymnosperm. Nevertheless, the cones are generally regarded as fruits, and will be so treated here.
The cones of many conifers are available in winter, either attached to the branches or scattered on the ground under the tree. They are, therefore, quite useful in winter identification. Like the fruits of Angiosperms, coniferous fruits may be dry or fleshy. In yew, the solitary seed is partially or wholly surrounded by a fleshy aril (Fig. 42). In pines and most other conifers of our region, there are numerous woody, leathery, or fleshy scales, each with one or more seeds, generally arranged about a central axis to form a cone (Fig. 40, 41). The cones generally remain closed while the seeds are developing, but open at maturity to permit the seeds to escape. The exposed portion of the cone scale in an unopened cone is known as the apophysis. In some species the apophysis is smooth, in others wrinkled, ridged, or grooved. When the cone opens, the apophysis can generally be identified because it is lighter in color than the portions of the cone which had not been exposed.
In several species the apophysis terminates in a small scar called the umbo. When the umbo is located at the tip of the scale, it is said to be terminal; if it is on the back, it is dorsal in its location. Umbos may terminate in prickles or spines, which are diagnostic and vary with the species, being straight or curved, weak or strong.
In the Pinaceae the scales are spirally inserted, but in the Cupressaceae (Thuja, Juniperus)they are opposite and decussate (Fig. 44). In most conifers the scales are woody or leathery, but in red cedar they are somewhat fleshy and the cone is berry-like in appearance (Fig. 43).