抄録
Two individuals with special flowering habit were found in a plantation for experiment of Kurile larch (Larix gmelinii var. japonica, from the Kurile and Saghalien) and named as V-544 and V-545 in 1968. They are very similar to ASFL-1 of Japanese larch (L. Ieptolepis) selected by Mr. MOMOSE in the district of Mt. Asama, Pref. Nagano (Table 2), in the habit of bearing only female strobili nearly exclusively on the annotinous growth of shoots, almost annually, and from early (younger) age (9 years of age in V-544), with a few minor differences among them. The clones of these two trees came to bear female strobili in 1〜2 years when budded on adult trees of Japanese larch in the crowns, while in 4〜5 years when budded on two-or three-year-old seedlings. In artificial crossings of inter-and intraspecific combination they produced moderate amounts of seeds. And the seedlings from these seeds grew as well as those of ordinary combinations (Table. 5). Therefore, these precocious trees can be utilized as temporary seed trees before the mass production of seeds of improved quality is realized, upon condition that their progenies will never serve as seed suppliers for practical silviculture. In the survey of the seed stand, in which the above-mentioned plantation has its seed source, at Numakawa, Wakkanai, in the spring of 1968, several trees were also marked by the similar flowering habit, and one of them (V-1481) was supposed as the mother tree of these precocious trees.
