Lilium auratum ssp. rubrovittatum

Red-band mountain lily

(Duchartre 1870)

The “red-banded auratum.” is one of the most coveted lily species by collectors and breeders.

Introduction

The red-band form of Lilium aratum (Fmr. "var. rubrovittatum") is one of the most unusual and sought after forms of L. auratum. Only about 2% of seedlings from seed-grown populations show red pigmentation at all, and true red-banded individuals are rarer still. Most fall into the pictum range, where pink or red appears only at the tepal tips or in papillae (tiny surface cells with yellow bases and red-tipped tops).

Description

Lilium auratum var. rubrovittatum, commonly known as the Red-Banded Gold-Banded Lily, is one of the rarest and most spectacular forms ever discovered within the Japanese Gold-Banded Lily complex. Although long recognized and highly prized by horticulturists, modern taxonomic authorities no longer recognize rubrovittatum as a distinct botanical variety, instead treating it as a color form synonymous with Lilium auratum var. auratum. This change reflects the current understanding that the red-banded plants do not represent a geographically isolated or genetically distinct population, but rather a rare naturally occurring color variant that occasionally appears within wild populations of Lilium auratum on the Japanese island of Honshu.

The typical Gold-Banded Lily is characterized by broad white tepals marked with a brilliant golden median stripe and numerous crimson spots. In contrast, the historic rubrovittatum form develops striking longitudinal bands of deep crimson to oxblood-red pigmentation running along the tepals, often partially obscuring the golden stripe and producing one of the most dramatic floral displays found in the genus. The intensity of this pigmentation varies considerably among individual plants, with only a handful of exceptional clones exhibiting the rich, continuous red banding that has made the form legendary among lily collectors.

Natural occurrences of rubrovittatum are exceedingly rare. Although no formal population studies have been conducted, experienced Japanese growers and Western horticulturists have consistently reported that only a very small percentage (>1%) of wild Lilium auratum seedlings develop noticeable red pigmentation, while truly outstanding red-banded individuals are encountered only very occasionally. This rarity, combined with the extraordinary beauty of the flowers, has made rubrovittatum one of the most sought-after forms of Lilium auratum for more than a century.

Despite its long history in cultivation, remarkably little scientific research has been conducted on the genetics of this unusual color form. No published studies have identified the genes responsible for the characteristic red banding, nor has the inheritance of the trait been fully investigated. Observations by at Oregon Bulb Farm by lily hybridizer and gneetisits Judith Freeman, as well as other experienced breeders indicate that crossing two red-banded plants does not reliably produce red-banded offspring, suggesting that the character is polygenic and controlled by multiple interacting genes rather than by a single dominant or recessive mutation. Hybridizers speculate that a “full-expression allele” may even be lethal when homozygous, which would explain why true-breeding strains have never been established.

Interestingly, all Lilium auratum plants carry the alleles for red/pink anthocyanins, but expression is inconsistent and genetically complex. Anthocyanins are expressed only in the epidermis, while carotenoids (responsible for the gold bands) penetrate the full petal depth, giving gold its solid richness compared to the more “surface-level” red.

Environmental factors may also influence the intensity and extent of pigmentation, further complicating breeding efforts. Notable clones at Oregon Bulb Farm such as T-39 and T-40 were preserved for their rarity and vigor. Later, renowned lily breeder Eddie McRae grew several excellent clones of var.rubrovittatum at Lava Nursery in Parkdale, Oregon, with the goal of producing a true “ox-blood” red hybrid. His goal was ambitious: to achieve the dark ox-blood red beauty of var. rubrovittatum, but combined with the garden vigor of hybrids. Pure rubrovittatum had never proven particularly strong or reliable in the garden, and McRae suspected that its limited vigor might be tied to its genetic makeup. He hoped to strengthen the line through hybridization without losing its unique color. Despite promising attempts, he admitted he was never fully successful, while many seedlings showed attractive red tones, none achieved the deep ox-blood coloration or other qualities he envisioned.

However, McRae found that crossing variety rubrovittatum with L. japonicum yielded second-generation seedlings with delicate pink tones and occasional red banding. Subsequent backcrosses to Lilium japonicum did not significantly improve or stabilize the strain, reinforcing the idea that red expression in auratum is governed by a complex, polygenic system rather than simple inheritance.

Selected clones such as T-39 and T-40 were preserved at the Oregon Bulb Farm for their exceptional longevity and performance, though they never yielded a stable rubrovittatum line. Sadly these clones were accidently kiled when a careless employee accidently sprayed them with weed killer. (J. Freeman)