Sunday, October 7, 2018

Norwegian Spruce Seed Extraction

When my Wife and I traveled to upstate New York to celebrate her birthday with hang-liding and hiking, we stayed in a little cottage set back in the woods on top of a mountain not far from Sam's Point. There was a tremendous Norwegian Spruce (Picea Abies) on the property which I took a liking to and collected some cones from under it's spreading crown to bring home in hopes of extracting seeds from them for next spring's growing season with intention to grow as a potted bonsai.

Norwegian Spruces are fairly recognizable in the wild when large. Their needled leafstalks will often droop from weight on older trees with old growth branches. They are a very large growing tree, reaching heights of almost one-hundred feet. Also noteworthy are their cones, which are the largest cones on any spruce variety. They often reach lengths of up to seven inches in length. Their origins are in Europe, however they've become naturalized to large parts of North America.

Collecting the seeds from these cones can be a simple process, as the cones are often found littering the ground under the tree's canopy. Find cones that are brown and appear recently to have fallen from the tree. If cones are on the tree and in reach, you can take cones direct from the tree, but ensure they are brown, not green, and that the cone-scales have begun to separate from each other. It takes a full year for cones to mature. Green cones have not yet reached an age to bear seeds. The cones which I collected were not uniform in seed quantity. The first cone I de-seeded contained about thirty seeds. The second cone, the cone photographed, contained about fifteen seeds. This cone was a little shorter than the other cone, but from the same tree.

I prefer to meticulously remove the seeds from cones, as opposed to other methods I've seen which involve drying them and slamming them on a table or heating them up and shaking them so the seeds fall out. I find that it's far less wasteful and more respectful of the specimen. Additionally, getting more seeds from the cone means I have a much greater opportunity to get successful germination rates. If I only managed to remove ten seeds, and my germination rates for the batch of seeds is low, I may only get several seeds to grow. I also find going through the cone scale by scale relaxing and meditative in a way. Before I started the removal process, I let the cones dry out for about two weeks. This ensured that the seeds would be dry and it would also be easier to work with the scales. Some other species require a dry period so that the cones simply open at all. Pitch Pine, for example, is extremely difficult when the cone is not dry.

The first step is to simply remove the top part of the cone. In my experience, there are not often many seeds in the top part of the cone with Norwegian Spruces. Most of the seeds are in the middle section of the cone. I simply broke off the top with a pair of pliers. Every cone is different, some are easier to work from the bottom up, others top down. I disposed of the top of the cone in a plastic bag which I put my other scraps in. This bag contains all my non-seed remains of the cones and other material. I empty this bag in a spot in my yard where potentially missed seeds will then maybe grow. I can then transplant these saplings later.

Each scale is attached to the central part of the cone very strongly. I use my finger to grip the cone as the plier is in the image to the right. Showing the process with the plier in place of my hand so that it is clearly visible. With my finger gripping the scale, I gently move the scale left to right, so that it pivots at the point where it is attached to the central cone-stalk. I continue to shift the cone-scale back and forth until it becomes loose and I can detach the scale from the stalk. The stalk is extremely fibrous and difficult to damage. When the cone is completely dry, these fibers become brittle, and break easier at the junction point.

Once you've remove several of the scales, the seeds should make themselves visible. You will see them poking out from behind other scales, laying on the inside of newly revealed scales, and simply see them fall or drop out of the cone from being disturbed from above. The hardest part of this process is removing the scales to reveal the seeds. As the scales are removed, the cone-stalk will be all that's left behind. When dry, it becomes pointy and sharp and will have to be broken off as you continue to remove more and more scales.

As I continue to remove the scales one by one, the seeds, which take the form of small samaras - or keys - reveal themselves on the inside of the scales. The seed itself is a small hard ellipsoid capsule near the base of the scale and the cone-stalk. The seeds are often loose by this point in the process from having dried out. Normally simply turning the cone over will let them fall out.

You can see three seeds on the left, as they were laying in the cone as I remove the scales. To the right, I have show a single scale, with the location of the samara on the scale as it would exist inside the cone. There are two samaras per scale however it's very common to only have one or even no seeds. On scales where a seed is stuck to the scale, I use a small exacto-knife to pop them loose from the scale. Occasionally, the samara will dislodge and leave only the seed. In this case, I simply discard the samara and keep the seed.


A single samara (left). Each samara contains one seed. The darker section of the samara is the seed. The lighter "wing" of the samara is simply to help the seed get carried distances in nature. Wind will blow the samara quite a distance should the samara exit the cone while it's high up on the tree. The wing is very fragile and easily disintegrates between the fingers.

The seed (right) is resilient. The seed is hard and protected by a shell that prevents it from germinating until the time is right as well as preventing damage to the important part of the seed inside. These seeds are the entirety of the cone's purpose: to nurture, store, and protect the seed until it is time to disperse it for potential growth.


Each species has it's own distinctive samara and seed. Norwegian Spruce seeds are medium sized. Pitch Pine samaras are slightly larger with wavy wings. Regardless of the species, the cone's purpose and structure is the same.

For storage, I use small plastic containers which I label with the species and year collected. There's no time-table for these seeds to go bad. They should last several years in storage in a cool, dry, dark place. This process of storing seeds works for practically any seed for any plant. Collection methods differ slightly depending on the type of plant, but the storage of all seeds is the same. It is very important that the seeds be dried out or dry to prevent them from becoming moldy.

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