Pinaceae Abies ziyuanensis L.K. Fu & S.L. Mo
Etymology
Abies refers to ‘to rise’; indicating large trees.
ziyuan refers to the Ziyuan County in China.
Colloquial Name
Ziyuan fir
Description
These trees can grow up to 30 meters tall, with trunks reaching 60 to 90 centimeters in diameter. The trunk is straight, cylindrical, and supports a broad, conical crown that becomes flat-topped in older trees. The bark is smooth and grey when young, but as the tree matures, it develops shallow ridges and grooves, breaking into small plates on the lower trunk.
The main branches are long and spread out horizontally, with those near the top angling upward. The smaller branches either spread outward or point slightly upward as well. The twigs are thick and sturdy, starting off light yellowish-brown and turning greyish-brown by their third year. Their surface is ridged and grooved between the leaves, sometimes with short hairs in the grooves, but otherwise smooth. The scars left by fallen leaves are circular.
The buds are cylindrical or slightly elongated with a somewhat pointed tip, covered in a thin layer of white resin. The protective scales of the buds are triangular, with a raised central ridge, and are a light yellowish-brown color. The leaves are arranged in a spiral along the branches and spread outward in two overlapping sets of different lengths, with the longest ones found near the base of each shoot. On cone-bearing branches, the upper leaves point slightly upward, while on young trees, the leaves are neatly arranged in two rows, widely spaced. They measure between 2 and 4.8 centimeters long and 3 to 3.5 millimeters wide. The base of each leaf is slightly twisted or curved, while the rest of the leaf is long, narrow, and either straight or slightly curved. Their surface is flat, with slightly curled edges when dry. The upper side is dark green, while the underside has two pale greenish-white bands. The leaf tips are either rounded or slightly notched. Stomata, the tiny pores for gas exchange, are absent on the upper side but form two bands on the underside, separated by a central ridge.
The pollen cones grow at the base of leaves along the branches and are about 2 centimeters long. They are yellowish, with small red structures that release pollen. The seed cones grow on short stalks, about 0.5 to 1 centimeter long. They are oblong-cylindrical or elliptical, with a rounded tip, measuring 10 to 11 centimeters in length and 4.2 to 4.5 centimeters in width. When young, they are greenish or yellowish-green, later darkening to greenish-brown and finally turning deep brown when fully ripe. After the seeds are released, the cone’s central axis remains as a narrow, cone-shaped structure.
The seed scales are broad and fan-shaped, measuring 2.3 to 2.5 centimeters long and 3 to 3.3 centimeters wide at the middle of the cone. Their surface is smooth, dark brown when mature, and covered in fine hairs in some areas. The upper edge is rounded and does not curl inward, appearing light brownish-green. The side edges have fine teeth and small ear-like extensions near the base, which is attached to a short stalk. The bracts, which are small modified leaves beneath the seed scales, are oblong and spoon-shaped, about 2.1 to 2.3 centimeters long, including a small pointed tip. They are around 9 to 10 millimeters wide at the top and 3 millimeters wide at the base. Most of the bract is hidden inside the cone, but near the base of the cone, some may extend slightly outward and curve backward. The upper margin of the bract has fine teeth.
The seeds are long and narrow, about 10 millimeters long and 4 millimeters wide, with a purplish-grey color and a coating of dark resin. Each seed has a broad, wedge-shaped wing that is slightly larger than the seed itself, measuring 13 to 15 millimeters in length and 12 to 14 millimeters in width. The wing has a rounded or slightly squared-off tip and is a light purplish-grey color with dark spots, giving it a glossy appearance.
Distribution
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TDWG Codes
3, 36, CHS, CHS-GX, CHS-HN, CHS-JX
Habitat
The natural habitats for Abies ziyuanensis are temperate forests. It is naturally found at an elevation of at least 1800 up to 1800 metres. There are no conifers associated with Abies ziyuanensis that are known of.
USDA Hardiness zone – 7
Abies ziyuanensis is hardy to USDA Zone 7 (Bannister & Neuner, 2001), meaning its frost tolerance lies somewhere in the range of -17.8C (0F) to -12.2C (10F).
Species Continuity
The population trend for Abies ziyuanensis is decreasing. Currently, there exist about 2000 mature specimen. There are ongoing threats for Abies ziyuanensis and they are listed as follows:
IUCN Category – EN
According to the IUCN Red List, Abies ziyuanensis has been assigned the status of EN(Endangered). This means that according to the Red List criteria, this species qualifies as Endangered and is very much at risk.
Superordinate Taxa
The nearest superordinate taxon for Abies ziyuanensis is Subsect. Holophyllae. The coordinate taxa for Abies ziyuanensis are therefore:
Abies ziyuanensis is further placed under Abietoideae. Abies ziyuanensis is also placed under Pinaceae.
This map shows botanical records (points) for this taxon. By opening the map’s sidebar (collapsed by default) you can toggle visibility or change the basemap. By clicking on records, you reveal more information.
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