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Pinaceae (Pinus )



Pinus (monticola )


Pinaceae

Pine


Pinus

monticola














western white pine

PIMO3


Western white pine is found from British Columbia to California and west to Nevada and Montana.


Seeds


Propagules (seeds, cutings, poles, etc.)

seed processing


Excerpt from the Woody Plant Seed Manual: Cones – Ovulate cones mature in 2 years, and are upright, shiny nut-brown, ovoid to oblong, 8 to 20 cm (3 to 8 in) long and are borne singly or in groups, and bear winged seeds with a body length of 3 to 4 mm (0.11 to 0.15 in) and wing length of up to 15 mm (0.6 in). Trees start bearing cones at 7 to 20 years and produce a good seed crop every 4 to 5 years in the Pacific Northwest.

Cones ripen in August and September. Cones can be collected by using ladders, hydraulic lifts, or by climbing trees, usually just before cones open. Cones should be dried quickly after harvest to prevent internal heating, mold development and rapid seed deterioration. Cones are put in burlap or mesh bags.

Pre-Processing – Cones can be opened by placing in a warm drying shed for several days or by placing them in a kiln 100 degrees Fahrenheit for 10 to 20 hours. Cones must cool before processing as pitch will stick to the seed and the machines. Processing – *Note: all processing of PIMO must take place in 60-degree temps or less. This includes tumbling, de-winging, screening, and gravity table. This is to ensure that excessive pitch does not accumulate on equipment or the seed. Extraction: Cones are tumbled to extract the seeds. While tumbling screens are used to remove as much pitch-dust as possible. Smaller lots are hand tumbled/sieved. Large lots, more than 10 bushels tumble over an LMC Vibratory Conveyor Model 3626.5 with screens to create separation. Pitch-dust is being removed in the first barrel, seed in the second and third, and cones traveling off the end of the tumbler. De-winging: Seeds are then de-winged using a Mortar/Mixer De-winger. Mixer if filled with approximately 3/4 barrel of seed for 6-8 minutes. Finishing: Seeds are then air-screened, using a Clipper Eclipse Model 324. First run: Top screen 12 round, 2nd screen 13 round, 3rd screen 13 round, bottom screen is a 6 round with balls added to the tray to increase action. The goal of the first run to remove all inert material possible, but not remove any seed. The top screen is scalping needles, cones scales, twigs and the air is focused on removing wings. Screen sizes could vary depending on the seed size and inert material present, but large rounds are used for this run. Second run: Use the same settings, but the top screen is covered with a solid insert over half of the area. This reduces the amount of time/opportunity the inert material has to go through the screen. The goal of this run is to remove more inert material and focus on improving the purity of the seed. Screen sizes and air varies by lot. Some smaller lots may be finished at this stage. Larger lots may be finished using a Gravity Separator, Oliver Model 30, (speed and air varies by lot), to remove remaining nonviable seed and inert material, and possibly if pitch is still present.














Herriman, Kayla . 2024. Propagation protocol for production of Propagules (seeds, cutings, poles, etc.) Pinus monticola Seeds seed processing; USDA FS - R6 Bend Seed Extractory Bend, Oregon. In: Native Plant Network. URL: https://NativePlantNetwork.org (accessed 2024/12/22). US Department of Agriculture, Forest Service, National Center for Reforestation, Nurseries, and Genetic Resources.