Dendrobium exile Schltr.
The stem of Dendrobium exile Schltr. is upright, thin cylindrical, somewhat woody, up to 50 centimeters long, about 3 millimeters thick, often branched in the upper part, and 2-3 internodes above the base are swollen and spindle shaped; The swollen stem is fleshy, measuring 4.5 centimeters in length and about 8 millimeters in thickness, with 4 edges. It is covered with a light white membranous sheath when young and reddish brown and glossy when old. Leaves usually alternate in the upper part of branches, upright, flattened cylindrical, measuring 2.5-6 cm in length and 1.5-2.5 mm in width, with sharp tips and leathery sheaths at the base.
Inflorescence reduced to a single flower, lateral to the top of branches, white, spreading; The flower bud is ovate, about 2 millimeters long, with a blunt pointed tip; The flower stem and ovary are slender, about 1 centimeter long; Sepals and petals are nearly lanceolate, with long and gradually pointed tips; The middle calyx is 1.7 centimeters long and about 2.5 millimeters wide, with 5 veins; The lateral sepals are approximately equal in size to the middle sepals, and the base is skewed to form angular calyx sacs with the stamen legs; The calyx sac is strong and straight, facing upwards, about 1 centimeter long, with a sharp tip at the end; The petals are 1.7 centimeters long and 1.5 millimeters wide, with 3 veins; The base of the lip is wedge-shaped, with three slits above the middle; The lateral lobes are obliquely semiovate triangular, with a few light purple spots on the inner surface, blunt apex, and wavy anterior edge; The middle lobe is narrow and round, with a sharp apex and wavy edges; Lips yellow, sparsely covered with long soft hairs, with three longitudinal ridges running from the base to the tip; The stamen column is 2 millimeters long, and there is one corpus callosum near the base of the stamen column foot; The medicine cap is conical in shape.
The capsule is spindle shaped, 4 centimeters long and 6 millimeters thick. The flowering period is from October to November, and the fruiting period is from November to December.
Dendrobium exile Schltr. is a perennial herbaceous plant that prefers shade and prefers to grow in warm, humid environments with an annual rainfall of over 1000 millimeters and semi shaded and semi sunny conditions. It is best grown in subtropical deep mountain forests with an average temperature of over 8 ℃ in January. The suitable growth temperature is 15 to 28 degrees Celsius, and the suitable air humidity is above 60%. It does not have strict requirements for soil and fertilizer. In the wild, it mostly grows on loose and thick bark or trunk, and some also grow in crevices. Belonging to the aerial root system, it mainly requires good permeability of the roots, and the substrate used should be well ventilated, breathable, and filter water. Under suitable temperature and humidity conditions, the growth rate is fast and the survival ability is very strong. At the end of spring and beginning of summer every year, flower clusters emerge from the upper nodes of biennial stems. After flowering, new shoots grow from the stem base and develop into stems. In autumn and winter, they enter a dormant period.