Endangered Whitebark Pine Ecosystems of
Northern British Columbia

• Seed Collection
• Nursery Seedlings
• Restoration Trials
• Restoration Treatments
• Community Involvement

Seed Collection

Restoration plantings of whitebark pine require high quality seeds collected from healthy parent trees that show either no sign of blister rust infection or evidence of a past infection that failed to spread, despite being surrounded by blister rust-infected trees.

At the northwest limits of its range, whitebark pine trees produce cones only intermittently and the quality of seeds at many sites is often poor, even in good seed years.  The Research Centre has been monitoring whitebark cone and seed crops in the Skeena Region since 2007:

2007: Excellent seed year province- and region-wide.  No seeds collected by BVRC

2011: Fair-good seed year in Skeena Region – many empty seeds.  First BVRC collection of 24,000 seeds

2013: Good seed year in Skeena Region. Second BVRC collection of 227,000 seeds

2018: Excellent to good seed year province-wide. Third BVRC collection of 483,000 seeds

In 2016, the Bulkley Valley Research Centre set a goal of collecting 1 million whitebark pine seeds from healthy parent trees, together with our partners in northern BC by 2021. To date, we have collected 734,000 seeds and are three quarters of the way to reaching our goal.

BVRC has now located, tagged and mapped 218 apparently blister rust-resistant parent trees at 13 locations across north central and northwest BC

Rust-Free Parent Trees in BVRC Seed Collections (2011 - 2018)

Site	Location	Trees	Years Collected
Jonas Creek	Telkwa River valley	12	2011
Hunter Basin	Telkwa Mountains	11	2013
Mount Sweeney	north of Tahtsa Lake	10	2013
Smoke Mountain	north of Tahtsa Lake	10	2013
McKendrick Pass	northeast of Smithers	2	2013, 2018
Eagle Pass	Babine Mtns. Provincial Park	15	2011, 2018
Higgins Creek	Babine Mtns. Provincial Park	7	2018
Mount Davidson	south of Vanderhoof	25	2013
Nanika Mountain	Morice Lake Provincial Park	14	2018
Mount Wells	northern Tweedsmuir Park	11	2018
Sibola Mountains	north of Tahtsa Lake	26	2018
Hudson Bay Mountain	west of Smithers	46	2011, 2013, 2018
Kidprice Lake	Nenikëkh/Nanika-Kidprice Provincial Park	29	2011, 2013, 2018
Total	13 locations	218 trees

 

In July, 2011, Don Pigott of Yellowpoint Propagation, a provincial cone collecting contractor, gave a 1-day cone caging and seed collecting training course that was attended by 10 volunteers and 2 workers.

Jodie Krakowski, a forest geneticist, volunteered her 2011 holiday time to assist us in selecting and caging trees and collecting and processing cones. Her expertise was invaluable in making highly technical decisions regarding tree selection, record keeping and cone processing.

John Kelson, a tree climber, conservationist and adventurer based in Smithers (deceased, 2019) did most of our caging in 2011 and 2013, and assisted with the collection in 2018. His enthusiasm, abilities and contributions to the early success of the BVRC whitebark pine restoration program cannot be overstated.  We have also benefitted from the tree-climbing skills of certified arborists Ross Wilkinson (Alba Environmental Consulting), Mike Plunkard, Charles Paquette and Kris Maxwell (Raincoast Arboriculture), Spencer Clark (Custom Climbing) and Dane Drizmotta (Sitka Creek Contracting). 

Cone cage on whitebark pine tree Hudson Bay Ski Hill Area May 2011

Seed drying and extractions have taken place in a large, heated, well-ventilated, rodent-proof space donated by BVRC director Brian Edmison (Edmison Mehr CA). Cones are dried aerated trays for 6 weeks or more. Seed extraction is a very labour intensive manual process, typically taking up to 1 month and involving local hourly-paid workers as well as volunteers from the Bulkley Valley Research Centre, BV Naturalists and BV Backpackers.  Following cleaning with an air separator to remove chaff and empty seeds, the seeds are weighed and sent to the BC Tree Seed Centre in Surrey for storage.

 

Representative seedlots are x-rayed by the BC Tree Seed Centre in Surrey. Good seeds (left) are large with a high percentage of filled cavities with mature embryos; moderate seeds (middle) often have immature embryos and unfilled cavities; poor seeds (right) are small and mostly empty. In both 2011 and 2013 we found that the most southerly seed sources from Mount Sweeney to Kidprice Lake produced the largest and best seeds while those from northern locations near Smithers have consistently produced, smaller, poor quality seeds.  We don’t know whether this is due to unfavorable weather, poor pollination or lack of outcrossing at the northern range limits where trees are scattered, or to a combination of  several factors. Alberta researchers have had similar problems obtaining high quality seeds at the northern limits of whitebark pine distribution, but excellent quality seeds were obtained from northern limit populations near Fort St. James in 2007.

Following advice from the Alberta Tree Improvement and Seed Centre, we tested an experimental ex-situ seed maturation process on some of our high elevation seeds in 2018. The purpose of the treatment was to allow the embryos of immature seeds more time to mature in the laboratory. When the cones were brought into the drying facility, instead of spreading them out on drying trays, they were immediately placed in plastic bags.  The cones remained in the bags at 90-95% humidity at room temperature for 6 weeks, then were removed from the bags and spread on trays to dry.  Fungal mycelia grew on the treated cones, requiring additional sanitation measures during seed extraction.  X-rays provided by the BC Tree Seed Centre have shown that BVRC seeds that received ex-situ maturation have embryos that average 41% (range 19% to 85%) longer than embryos from the same high elevation seed family that did not receive the maturation treatment. Previous work by Alberta researchers on limber and whitebark pines suggests that the ex-situ matured seeds will remain viable for longer in storage and that they will ultimately have a higher germination rate or require a shorter period of warm stratification to germinate successfully.       

 

This blister rust resistant pine, growing at McKendrick Pass, near the northern limit of whitebark pine, produced significant cone crops in 2007 and 2018, but no cones in the intervening years.

 

Dried seeds are stored at the BC Tree Seed Centre until needed. Operational seedlots meeting the Chief Forester’s Standards for Seed Use are registered in the SPAR system. These seeds are available for general restoration use.  Please contact the Bulkley Valley Research Centre to enquire about seed availability for your northern BC whitebark pine restoration project.  Seeds for gene conservation, blister rust screening, other research purposes and for planting in BC Provincial Parks are stored individually by seed family (1 parent tree) and are not available for general use.

Rust Resistance Screening

An essential component of seed collections from apparently blister-rust resistant whitebark pine parent trees is blister-rust screening to test whether progeny from parent tree are actually resistant to white pine blister rust.  Rust screening trials take place under controlled conditions in a nursery or laboratory setting, or under field conditions.  In the laboratory trials, leaves collected from infected Ribes  (gooseberries or currants) are placed on a screen above container-grown whitebark pine seedlings from selected seed families, just prior to the release of spores. Spore fall is monitored until the desired inoculum density is reached. Ribes leaves are then removed and the temperature is raised to 20° Seedlings are left in the inoculation chamber for approximately 48 hours to ensure spore germination and infection of the pine needles, then the seedlings are transported outside and monitored over 5 years for disease symptoms (initially, needle lesions or spots) and mortality.

Since 2014, the Bulkley Valley Research Centre has contributed seeds from our 2013 and 2018 seed collections for rust resistance screening nursery and field trials in BC and the western US.  As intake in each year is limited, it will take many years before all 218 families in the Parent Tree Table (above) are screened.

Seed Families Submitted by BVRC for White Pine Blister Rust Screening

Date	Screening Program	Number of Families	Number of Locations	Results
Dec. 2013	BC inoculation trial (Murray, Kalamalka Forestry Centre) BC field trial (Cartwright, several locations across BC)	15	4	early inoculation trial results: 4 high; 3 moderate; 4 low, 4 very low resistance.
July 2014	USDA Forest Service (Maholovich, Moscow, ID)	6	6	none yet
Oct. 2017	BC inoculation trial (Murray, Kalamalka)	3	2	none yet
March 2019	USDA Forest Service (Sniezko, Dorena, OR)	87	9	trial delayed due to funding shortfalls
Oct. 2019	BC inoculation trial (Murray, Kalamalka)	11	8	seedlings being grown at Sylvan Vale nursery. Not inoculated yet.

 

Our best-performing seed families so far include two families from Kidprice Lake in Nenikekh/Nanika-Kidprice Provincial Park, one family from Hunter Basin in the Telkwa Mountain Range and one family from the Rhine Crag mining road on Mount Sweeney.   One of the Kidprice families (from a beautiful open-grown ridge-top tree known as K9), has the highest resistance to blister rust of any tree tested in British Columbia so far.

Interestingly, northern seed families have tended to perform better in inoculation trials carried out in the US and southern BC than southern families.  In fact, of 27 families inoculated at Kalamalka Forestry Centre in 2016, the top 7 (and 9 of the top 10) were BVRC families from the Skeena Region.  This is a very encouraging early result from our seed collection program but could be an artefact of the inoculation regime that may not hold up in field trials. The 87 seed families sent to Dorena in 2019 are part of a more comprehensive study to investigate why northern families perform so well in these tests.

Families that perform well in blister rust screening trials will be propagated in several new whitebark pine seed orchards planned for BC. Some resistant seedlings from the trials may be transplanted directly into these seed orchards.  Scions will also be taken from the highest performing parent trees and grafted onto root stock.  This is a time-tested method for obtaining cones and seeds from superior trees that is used elsewhere in BC to produce genetically improved (“A” class) tree seed for commercial tree species such as Douglas-fir, white spruce and lodgepole pine.