Most conifers are evergreen; however, species such as dawn redwood (Metasequoia glyptostroboides), golden larch (Pseudolarix amabilis), bald cypress (Taxodium distichum), and all species of larch (Larix spp.) are deciduous, which means that they lose their needles each fall and develop new ones each spring. Golden larch and dawn redwood are particularly striking in fall, when their needles turn color before falling.
True cedars (Cedrus spp.) and larches (Larix spp.) bear short needles arranged in clusters or whorls. Pines (Pinus spp.) have needles arranged in fascicles: small bundles of two, three, or five needles bound together at the base by a sheath. The rest of the needle-leaved evergreens have single needles set individually along the twig or branchlet.
Spruce (Picea spp.) needles are sharp-tipped, set singly on stout twigs in spiral lines, with each needle sitting on a woody peg that protrudes from the twig. Firs (Abies spp.) bear blunt-tipped needles that lack woody pegs and often appear to be arranged in two ranks along the stem. Hemlock (Tsuga spp.) needles are short, blunt-tipped, and flat, and the undersides of needles display two distinct white lines, which are actually stomates (leaf pores).
The cones of pine, spruce, and hemlock are pendulous (hanging downward). In contrast, cones of fir and cedar are held erect on the branches and shatter when mature.
The Conifer Collection is comprised of 556 gymnosperm taxa (kinds) representing 195 species, 30 genera, and 8 families. The main tract occupies twenty-four acres (10 hectares; excludes Hemlock Hill) and is arranged to facilitate the study of cone-bearing plants. Just like flowering plants, conifers form seeds. However, instead of being enclosed in fleshy fruits, the seeds of conifers are protected in cones. These seed cones are the female reproductive structures of conifers. Conifers also have pollen-bearing cones, which are the male reproductive structures. Male and female cones can occur on the same plant or on separate plants. Accurate identification of conifers requires an examination of the cones; however, leaf (needle) characteristics are also important clues to identification.
- Find directions and accessibility information for this collection
- Explore more conifers in the Gymnosperm Database
- Visit the American Conifer Society website
Plants in this Collection
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