Seed production from the Korweinguboora seed orchard.  L.A. Pederick.  April 1972.  22 pp. (unpubl.)

SUMMARY

1. Seed yields from the Korweinguboora seed orchard have progressively increased since the first harvest in January, 1969. In the oldest portion of the orchard, unit 1 (established 1960-62) yields have been 2.3, 4.2 and 6.1 pounds of seeds per acre at 7½, 8½ and 9½ years respectively from the average date of planting. The 1972 harvest, which has been collected but not yet extracted, should yield about 215 pounds (12 pounds per acre in unit 1).
2. Estimates of the yields to be obtained in 1973 and 1974 have been made, and are 302 and 358 pounds respectively (17 and 18 pounds per acre in unit 1, 11½ and 12½ years after establishment).
3. The average number of sound seeds per cone has increased each year from 56 in 1969, and 77 in 1970, to 78 in 1971. The lower figure for 1969 is a consequence of limited pollen production in the early stages of orchard development. Further increases in the number of full seeds per cone are expected, with a consequential increase of total orchard yield.
4. The seed crops of individual clones for the 1969, 1970, 1971 harvests have been studied. Considerable clonal differences have been found in cone production, number of seeds per cone, and seed weight.
5. The Korweinguboora orchard is compared with other orchards in Australia, and is found to be one of the least productive - at least, up to the present time. It is at a higher elevation and experiences a colder climate than the other orchards, so it is suspected that climate, possibly temperature at some critical time of the year, may be affecting the initiation of flower primordia. Soil fertility appears to be very good.

Also published:

Pederick, L.A. and Brown, A.G. (1976)  Seed production in radiata pine seed orchards in Australia.  Aust. For. 39 (3): 164-79 (part).