Index

Provenance program - coniferous

Provenance program - hardwoods

Provenance research in the B.C. Forest Service has a long and important history. Most of the initial provenance trials were established under the auspices of International Union of Forestry Research Organizations (IUFRO), which were large scale collections of important species such as Douglas-fir, Sitka spruce and lodgepole pine. Additional provenance testing has been established in almost all other species, which has been instrumental in our ability to develop seed transfer guidelines, identify superior provenances, and delineate breeding zone boundaries. They also now form the basis of our large effort in predicting the impacts of climate change, to species and seed lot choices in the future (e.g., see Seed Transfer and Climate Change).

Below is a small subset of recent activities in a few of the programs. For more information on the status of provenance research, the individual scientists noted on the updates can be contacted.

All Hemlock Seed Planning Unites - Seed Transfer Concerns (Charlie Cartwright)

Further gains from the hemlock breeding program may be achieved through expansion of the area where material genetically superior in growth traits may be safely planted. Currently seed transfer limits are set based on older information from other species plus hemlock trials intended for other purposes. The progeny tests that compare the field performance of different parent trees are not suited to determining this question because they are relatively complex and need good survival to rank the parents. In contrast, smaller, simpler seed transfer (provenance) trials provide best information when many of the test trees are adversely impacted by the harshness of the environment. This establishes the level of adaptation of high gain materials to ground beyond where it has been tested in the family trials. Due to the variability of B.C.'s climate resulting from proximity to the sea, and mountainous terrain the number of test sites needed to establish the bounds of safe seed transfer are relatively many. For this reason about 35 small hemlock seed transfer tests comprised of wild stand and tested seed sources have been widely dispersed in BC over the last ten years. Highlights of this year's activities in these trials include weeding 8 of the younger sites, plus 7 were measured. Next year another 2 test sites will be measured. Patience is required, however, since revision of seed transfer boundaries can not commence until plants have been exposed to a range of environments for at least 10 years.

Lodgepole Pine Provenance Update - (Cheng Ying)

Lodgepole pine has been the focal species of the provenance research program in the past several years: updating its seed transfer guidelines, developing empirical models, predicting quantitative relationships between growth and climate variables, and analyzing pest data gathered from 1993-95 to guide selection of resistant seed sources.

Seed transfer guidelines of lodgepole pine are updated according to the cumulated provenance testing results. Transfer of natural seed sources will depend principally on floating distance (geographic origin of the seed source as the determinant of transfer distance) with emphasis on directional transfer from east to west and low to high elevation. Seed planning zones are realigned to improve overlay between genetic patterns of geographic variation and biogeoclimatic classifications. The draft report on these revisions with supporting rationale and evidence is completed.

To take advantage of the extensive lodgepole pine provenance tests and the massive amount of growth data generated, a study was initiated to construct empirical models which quantify mechanistic correlations between climate variables and growth/yield, with the ultimate goal to establish the quantitative relationship of plantation forests for sequestering atmospheric CO₂. The study involves the cooperation of Dr. G. Rehfeldt (USDA Forest Service) and Dr. D. Spittlehouse (Research Branch). We have successfully constructed models with high predictability, using climate variables such as mean annual temperature, mean temperature in the coldest month, or mean summer precipitation, to predict growth of seed sources in relation to environmental gradients within the species’ natural range in British Columbia. Management applications of these models include guiding reforestation, seed source selection according to environmental conditions, i.e. match an optimal seed source with a planting site according to the site’s current or future environmental conditions, deployment of genetically improved trees and gene conservation, and predicting consequences of environmental change on the adaptedness of our forests (For more details, see: Genetic responses to climate in Pinus contorta: niche breadth, climate change, and reforestation. 1999. Ecol. Monographs Vol. 69. Rehfeldt, G.E., C.C. Ying, D.L. Spittlehouse, D.A. Hamilton Jr. ) 

Considerable effort has been directed to analyze the pest data collected in 1993-95 from the lodgepole pine provenance tests, also funded by Forest Renewal BC. We have identified provenances highly resistant to western gall rust (Endocronartium harknessii) and needle cast (Lophodermella concolor); these provenances also exhibit high level stability across diverse site environments (low provenance x site interaction). We are continuing the analyses to quantify the effect of these diseases on growth.

True Firs (Charlie Cartwright, Doug Ashbee)

Pacific Silver Fir

There were 4 Pacific silver fir sites planted in 2002, all of which were weeded this year as were 5 of the 8 tests planted in 2003. Of the un-tended trials, one near Hope was destroyed by wild fire, a second was inaccessible due to a bridge out and at the third un-weeded site we did not have sufficient time to complete the task on this relatively remote site. First data beyond nursery results will be taken on the older series in the next fiscal year. As well, replacement planting of the site that burned is planned along with beefing up planting of the others.

Grand Fir

The species' subcommittee considered declaring superior seed sources based on age 20 data from 8 provenance test sites. The top source, (Salmon River), produced 12% more volume than other well adapted sources for the seed planning unit. Once juvenile/mature correlations were considered the advantage of this provenance was 8%. The species' sub-committee will not recommend the use of this source for B+ seed until it can be ascertained that enough trees remain at the source to make seed collection feasible.

Subalpine Fir

Four nursery trials for this species were established in 2002. One has had to be abandoned due to poor survival. Of the remaining three, two were in need of intensive maintenance. Measurements for growth on 2 sites will be carried out next fiscal year, and on one site for Christmas tree traits. To cover gene conservation concerns and long term growth data, excess replacement stock will be out-planted to 2 new field sites in the coming year. The adelgid quarantine will limit the scope of this, so sowing of new tests targeted at the North Interior of B.C. will also be undertaken next year.

Noble Fir

As with grand fir, identification of superior provenances to produce B+ seed is under consideration by the species' subcommittee. Based on age 16 data from 12 sites the top source was 11% in volume beyond averages for other well-adapted provenances. After consideration of juvenile/mature correlation the gain achievable was about 6%. Similar to the situation for grand fir, the viability of using the chosen superior seed source near Mt. St. Helen's, (French Butte) will be checked in the field. Other good provenances are in ecological reserves/parks, or logged; the Mt. St. Helen's trees are USDA National Forest and young mature.