Koyanishi

Koyanishi is a Shizuoka sencha cultivar registered in 1953 as Cha Norin No. 8 (茶農林8号), one of the fifteen tea varieties in Japan’s first-ever official cultivar registration — the same batch that gave Yabukita its Cha Norin No. 6. It was selected by Sugiyama Hikosaburo, the same grower who found Yabukita, from an individual tree that stood, the registration record says, on the west side of a hut. Unlike Yabukita, Koyanishi never left Shizuoka: the 1953 record recommends it for Shizuoka Prefecture only, and it was struck from the prefecture’s own recommended-cultivar list in 1955 — the very year Shizuoka began actively promoting Yabukita. Where Yabukita became the coordinate system every other cultivar in Japan is measured against, Koyanishi is closer to a footnote in the same breeder’s catalogue: formally registered, briefly regional, then eclipsed.

Lineage

• An individual tree selected by Sugiyama Hikosaburo — found on the west side of a hut (“koya”, 小屋), at a place the registration record does not name; contributes the whole of the cultivar, as an unmixed landrace selection rather than a cross.

Koyanishi is a single-tree selection, not a controlled cross, so it has no recorded pollen parent — the same situation as Yabukita. MAFF’s Cha Norin registry table records the seed behind that tree as 宇治在来種実生, a seedling of the Uji landrace, which the 1953 journal record neither states nor contradicts. It was registered alongside two other Sugiyama selections in the same 1953 batch, Yabukita (Cha Norin 6) and Rokuro (Cha Norin 9), with Makinohara-wase (Cha Norin 7, a separate Shizuoka selection by a different breeder) sitting between them in the numbering. No source consulted for this record names a descendant bred from Koyanishi.

History

Registration, 1953

In fiscal Showa 28 (1953), the Ministry of Agriculture and Forestry named its first-ever batch of officially registered new crop varieties, and fifteen of them were tea — the same event that produced Yabukita’s registration. The record was published in 茶業研究報告 (Chagyo Kenkyu Hokoku, the Tea Research Journal) No. 2, October 1953, under the title “茶の品種登録と命名” (“Registered Tea Varieties and Their Naming”). The article notes that most of the fifteen had already spread to some degree in cultivation before being formally registered, so the registration was catching up with existing practice rather than launching something new.

Koyanishi’s entry in that record gives: registration number Cha Norin No. 8; former strain name (旧系統名) 小屋西; selected by Sugiyama Hikosaburo and developed between 1935 and 1946 (Showa 10–21) at the Shizuoka Prefectural Tea Experiment Station’s Ministry-designated original-seed orchard. Sugiyama — the same grower who, in 1908, picked Yabukita and Yabuminami from either side of a bamboo grove — here named a tree for a different landmark: it stood on the west side of a hut, giving “koya” (hut) plus “nishi” (west). The record gives no location for the hut.

The 1953 record classes Koyanishi as chuban (medium-season), though picking is noted to begin a little early for that class, and reports it as good quality for ordinary sencha (普通煎茶) — a workmanlike rather than standout appraisal, and one limited explicitly to Shizuoka Prefecture: no other suitable region is listed, unlike the national reach Yabukita would go on to have.

A prefectural cultivar that lost to its stablemate

Japanese Wikipedia’s biographical entry for Sugiyama records a detail the wider tea-cultivar literature omits: Koyanishi, and Rokuro alongside it, had already been designated a Shizuoka Prefecture recommended cultivar (奨励品種) in 1937 — sixteen years before its formal MAFF registration. Both were then removed from that same prefectural recommended list in 1955. That is the exact year Shizuoka began actively promoting Yabukita for planting. The timing reads as a changeover rather than a coincidence: Koyanishi held prefectural favour through the interwar years and into the immediate postwar period, and lost it in the same year, to the same breeder’s other, more versatile selection.

No source found documents Koyanishi in cultivation after that point. It does not appear in any of the vendor, retailer or specialist reference sites surveyed for this record, nor on Ito En’s cultivar-characteristics page, nor in Kyoto Prefecture’s own list of Uji-origin cultivars, nor anywhere in the JSTAGE Tea Research Journal archive beyond the 1953 registration notice itself.

Characteristics

The 1953 registration record is the only detailed characteristics source found for Koyanishi, and it is brief. It is classed as a medium-season (chuban) cultivar, though picking is noted to begin a little earlier than that class implies; no day-count relative to Yabukita has been sourced. Growth habit is upright (直立) with strong vigour (樹勢強); the leaves are elliptical and large; the young buds are described as somewhat yellow-green. Quality is reported as good for ordinary sencha (普通 煎茶として品質良好) — solid rather than distinguished, and the only appraisal recorded for it is a plain “good,” with none of the specific flavour or aroma notes given for cultivars from the same batch that went on to wider release.

No yield figures, disease-resistance data, or cold-hardiness assessment survive in the sources checked, and none is invented here. Nor does any cup description — aroma, flavour, colour — appear in any source available: Koyanishi does not seem to have been written up as a tea to drink, only registered as a plant. That absence is itself informative. Yabukita’s profile of cold hardiness, high yield and processing versatility is documented in detail precisely because those traits carried it across the whole country; Koyanishi’s characteristics were apparently sufficient for a Shizuoka-only recommendation and no more, and once the same registry board had a better version of the same basic proposition on offer in 1955, Koyanishi had no distinguishing trait on record to fall back on.