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Fokienia

Fujian cypress, A. Henry & H.H. Thomas  1911
Cupressaceae

 

Evergreen trees with a straight single main trunk clothed with smooth to furrowed, fibrous bark peeling in vertical patches or strips. Crown cylindrical to dome-shaped, densely branched with horizontal or gently drooping branches. Branchlets in flattened fernlike sprays with alternate branching. Scaly winter buds lacking. Seedling leaves in alternating quartets, needlelike, standing out from and well spaced on the stem. Seedling phase short-lived with even the first lateral branches bearing juvenile rather than seedling leaves. Juvenile and adult leaves in alternating pairs but appearing nearly whorled, scalelike, the facial and lateral pairs dissimilar, clothing the branchlets, without resin glands. Facial leaves wedge-shaped, the broadly pointed tip overlapping the bases of the next facial leaf and lateral pair. Lateral leaves completely separated by the facial leaves, broadly and prominently keeled, their tips rounded in adults and sharply pointed in juveniles.

Plants monoecious. Pollen cones numerous, single (or up to three together) at the ends of short branchlets, spherical, with (three to) five or six alternating pairs of pollen scales, each with three pollen sacs. Pollen grains small (30-35 µm in diameter), nearly spherical, with a short germinal papilla, otherwise almost featureless. Seed cones well separated, single at the ends of slender short branchlets, maturing in two seasons, nearly spherical but slightly longer than wide, with six to eight alternating pairs of peltate, woody seed scales. Each cone scale formed by complete fusion of the seed scale and subtending bract, with a hexagonal or pentagonal face crossed by horizontal furrow with a central point representing the free bract tip. Middle three to five pairs of scales each with two seeds. Seeds oval with two very unequal wings derived from the seed coat in the upper half, the outer wing (facing away from the adjacent seed) up to the same size as the seed body, the inner wing much smaller. Cotyledons two, each with one vein. Chromosome base number x = 11.

Wood of medium weight and strength, with a narrow band of light reddish brown sapwood sharply contrasting with the dark yellowish brown heartwood. Grain fairly even and very to moderately fine, with well-defined growth rings marked by an abrupt transition to narrow band of much smaller but not much thicker walled latewood tracheids. Resin canals absent but with numerous individual resin parenchyma cells scattered through the growth increment or occasionally concentrated in loose bands.

Stomates in very prominent white stomatal zones on the undersides of the branchlets. Each stomate set beneath and partially hidden by the five to seven surrounding subsidiary cells, which are often shared between neighboring stomates, are topped by a steep, often interrupted Florin ring, and also bear other prominent individual papillae. Leaf cross section with a single-stranded midvein above a single resin canal and flanked by short wedges of transfusion tissue. Photosynthetic tissue forming a thin palisade layer beneath the epidermis and adjacent thin hypodermis on the face of the leaves occupying the upper side of the branchlets with spongy mesophyll extending down to the stomatal zones.

One species in eastern Asia. The foliage of Fokienia (the name honors coastal Fujian province of China, from which it was originally described, discovered by Captain A. Hodgins about 1904 and introduced to cultivation by Admiral Clinton-Baker, who sent two plants to his brother’s collection at Bayfordbury, Herts, in 1909.) somewhat resembles that of Thujopsis, though of thinner texture, while the seed cones are similar to those of Chamaecyparis, to which it is closely related according to DNA sequences. With its requirement for a warm, very humid climate, Fokienia hodginsii is grown to a very limited extent in horticulture, and there has been no cultivar selection.

Fossil specimens of Fokienia with foliage and seed and pollen cones are found in the Paleocene of western Canada, while similar foliage is widespread, if uncommon, at the same time elsewhere in western North America and has also been found in northwestern China and much later, during the Miocene, in the northwestern United States. These fossils differ from the living plant in having the branchlets with opposite branching and the seed cones in pairs, replacing branchlets. The seed wings are also equal and extend all the way around the seed. There are no known fossils with intermediate features.

 

 

Species:

 

Attribution from: Conifers Garden


 

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