Conifers , or conoid - have tree , are mostly evergreen and have thin , spiky leaf called needles . Conifers include the pine , fir and titivate families . The conoid of these trees vary widely in sizing , gloss and texture , but all carry and protect the tree ’s seeds until they are matured , at which point the cones expel the seeds to the winds . Some deciduous trees also form heavily , conic - shaped seed pod , but these are properly called catkin rather than cones .
Pine and Sequoia Cones
Trees species in the pine phratry ( Pinus spp . ) are coniferous tree with long flexible needles . Pine tree seeds are have in retinal cone that vary widely in size of it bet on the species , but all are characterise by hard , woody scale attached to a cardinal stem . Once the cone opens and the pine seeds are released , pine scales remain attached to the central meat , lead in a hard , pyramidal shaped cone cell which is very attractive for many craft uses .
Sequoia cone cell disagree from pine cones in that the bract , which , according to Charles Bessey writing on the " Morphology of the Pine Cone " for the University of Nebraska - Lincoln in 1902 , are part of the stamens or generative organs of the sequoia prime , comprise the dominant seeable structure of the cone . alternatively of unresolved petal - alike scales such as on a pine strobilus , the sequoia cone seems to be a serial of rhombus - work woody blocks with narrow diagonal openings in between them which release the sequoia seeds .
Spruce and Fir Cones
Spruce cones are softer than pine cones , according to the University of Saskatchewan Extension . Spruce strobilus scales are thinner , generally down pointing toward the tip of the strobilus , and remain flexible rather than becoming woody like those on a pine retinal cone . Fir cones look interchangeable in structure , but grow point up on the tree diagram limb , not hanging downwards like spruce cones . The Saskatchewan Extension note that fir cone scales are also deciduous – they precipitate off of the central conoid axis each year , give the core of the cone remaining suffer upright on the tree branches .
Catkins
Many deciduous Sir Herbert Beerbohm Tree , including birch rod ( Betula spp . ) , alder ( Alnus spp . ) and pecan tree ( Carya illinoinensis ) blossom in descend , tapering spikes that , accord to the University of Massachusetts Extension Service , are properly visit catkins . In many of these tree varieties , particularly alders , the supporting stem skeleton of these catkins hardens into a woody , conical structure after flower is completed . While these structures are ordinarily referred to as cones , and are often used in slyness and ornament along with pine cones , botanically they continue catkins , or catkin carapace , as the trees they come from are not conifer .
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