Judging Center: St Paul Minnesota
Award Number: 20202562
Award Date: January 25, 2020
Awarded As: Dendrobium rutriferum
Purchased from Andy's orchids, labeled as Dendrobium erosum, I grew it for several years before entering it into a show and at that point decided to cross reference the identification to ensure it was correct since it is a relatively obscure dendro. I noticed that the descriptions I could find for D. erosum did not match my plant. The flower descriptions are quite similar but the plant shapes are very different. I discovered a website, orchidsnewguinea.com, a database of orchid descriptions from over 142 genre native to Papua New Guinea, and I found the photo, description, and for the first time the name Dendrobium rutriferum. I believe the description is a reprint from Lindenia which also has an illustration of the plant. Dendrobium erosum is described as a slender plant with thin bamboo like leaves and sheaths that cover the stems unlike rutriferum, which has fusiform shaped bulbs, broadly lanceolate leaves, and sheaths that do not fully cover the stem. I believe these are the major distinctions between the 2 plants.
Thanks
Plant > Overall length of growth/cane: at least 30 cm and up to 90 cm
Plant Leaf > number of leaves per growth or cane: carrying up to 35 leaves per growth
Plant > Leaf Length: 11.25
Plant > Leaf Width: 3.75
Plant > Leaf Margin: smooth overall, dark green
Plant > Leaf Shape: broadly lanceolate, goes deciduous from the base up over the course of 2 to 3 growing seasons
Plant > Leaf petiole length (apex of pseudobulb or stem to leaf base proper): very short and almost disappears as the leaf widens immediately
Plant > Pseudobulb/Growth/Ramicaul Length: 90 cm
Plant > Pseudobulb/Growth/Ramicaul Width: 1.25
Plant > Pseudobulb/Growth/Ramicaul Margin: elongated, fusiform, grooved longitudinally, purple marked with sheaths that do not fully cover the cane
Plant > Pseudobulb/Growth/Ramicaul distance between growths along rhizome:: closely spaced, 1.25 cm
Plant >Pseudobulb/Growth/Ramicaul Root Tip Color: green
Inflorescence > Overall Length: 2.5-3.75 cm overall
Inflorescence > Arrangement: 3 to 5 short, racemose, many flowered to 50 per inflorescence per growth
Inflorescence > Distance from base of inflorescence to first bud or branch: .25 cm they start almost immediately and cover the whole inflorescence
Inflorescence > distance between flowers along inflorescence: very close like 1 mm, very densely packed
Inflorescence > distance from inflorescence to base of sepals: 1.25 cm
Inflorescence > distance from inflorescence to base of sepals: 1.25 cm
Inflorescence > Floral Bracts Length: triangular to 2 cm
Inflorescence > Floral Bracts Width: .5 cm
Inflorescence > Ovary Length: .625 cm
Inflorescence > Ovary Width: 1-2 mm
Inflorescence > Ovary Shape: slightly larger than the stem
Inflorescence > Ovary Color: pink, darker than the flower
Inflorescence > Ovary Texture: smooth with small grooves
Flower Natural Spread Length: 1.0 cm
Flower Natural Spread Width: 1.1 cm
Flower > Dorsal Sepal Length: .8 cm
Flower > Dorsal Sepal Width: .6 cm
Flower > Lateral sepals or synsepal Length: .7 cm
Flower > Lateral sepals or synsepal Width: .45 cm
Flower > Petals Length: 1.6 cm
Flower > Petals Width: .7 cm
Flower > Lip or Pouch Length: 1.2 cm
Flower > Lip or Pouch Width: .4 cm
Flower > Lip or Pouch> characters of lip (calli, spurs, keels, etc.): lingulate and pandurate, callus above the base, apex is calceolate with a finely denticulate margin. Flowers are bright pink sepals and petals are white tipped and the texture is crystalline
Flower > Column Length: .2 cm
Flower > Column Width: .2 cm
Flower > Column Color: white
Flower > Anther Cap Color: off white