Celebrating Seeds

I’ve been seeing a lot of brand new plants germinating from seeds during the last couple weeks. Looking at all those cotyledons (first leaves) poking out of the ground makes me reflect on the massive amount of good fortune it takes for any seed to actually turn into a new prairie plant.

Prairie dandelion seeds (Nothocalais cuspidata).

Seed production is a high risk, high reward strategy for plants, and even that’s a huge understatement. It takes a tremendous amount of energy for a plant to produce a flower – especially if you’re trying to make one that’s attractive to an animal pollinator. There’s all the colorful petals or other structures, nectar (in many cases), and, of course the pollen itself. After pollination, even more energy can go into loading up the developing seeds with the nutrition and energy needed to give the embedded embryo a chance of success.

Once the seeds are released from the plant, they often travel away from their parent – at least far enough that they aren’t trying to grow directly beneath them. The varied tactics used by plants to disperse their seeds is a huge, fascinating topic, which I’ve written about before. Regardless of whether a seed travels by wind, water, attached to the fur or feathers of an animal, or by being eaten and then pooped out, there are myriad dangers along the way.

Prairie violet (Viola pedatifida) seeds can travel in two ways. First, they are ballistically launched into the air as their pods dry and constrict. Second, many are picked up and carried home by ants because of the little fatty packet of nutrition (elaiosomes) violet seeds have attached to themselves for that very purpose.

Seeds packed with nutrients to feed their embryo are also a great food source for many other organisms. Countless vertebrate and invertebrate animals seek out and eat seeds, especially during the dormant season when most other food sources are scarce. Fungi and lots of microorganisms can also destroy and consume seeds.

Pasque flower (Pulsatilla patens)

If, by some minor miracle, a seed survives its short or long journey intact, it may still be a long way from ultimate success. For most plants, germination only happens if a seed is in good contact with soil. Think for a moment about the world a seed is launched into and how many obstacles there are between that seed and the soil!

When you walk through most prairies, if you look straight down, you’re not seeing a lot of bare soil. Instead, there are a lot of living and dead plant parts (leave, stems, etc.) between your feet and the ground. A recently-burned prairie, of course, has lots of bare ground. That’s a great opportunity, but only for any seeds who weren’t consumed by the fire itself.

Most seeds land on something besides soil. Often, that’s the end of their journey and they sit there until they die (e.g., the embryo runs out of stored food) or they’re found and consumed by another organism. If they’re lucky, they might get dislodged from their original landing spot by wind or rain, for example, and slip downward toward the soil.

Entire-leaf rosinweed seeds (Silphium integrifolium)

Let’s say a seed has led a lucky life and manages to reach soil. It might even get pushed into that soil slightly by rain or a passing animal’s foot. Hooray! Now it can grow and reward its parent’s huge investment.

Well, maybe.

Most seeds need water to germinate. During drought periods, a seed might sit in the dusty earth for weeks, months, or years, waiting for sufficient moisture to help break its seed coat open. As it sits there, it’s vulnerable to any passing animal, fungal hyphae, or tiny microorganism looking for a meal. Plus, as we discussed earlier, the embryo might simply run out of food.

Dotted gayfeather (Liatris punctata)

Even if rain or snow provides sufficient moisture for germination, some prairie seeds also need a certain amount of sunlight to trigger germination. (This is why it’s important not to plant prairie seeds like you plant pumpkin or green bean seeds. Just scattering them on top of the ground is often best.) If a seed that requires light lands on bare soil that happens to be in the shade of other plants, it might still be stuck in limbo.

Illinois bundleflower seeds have such a strong seed coat they can survive a trip through the digestive system of an animal. That’s great for the seed, but doesn’t provide any reward for the poor hungry animal!

As a result of all the challenges they face, only a tiny percentage of seeds released into the world by their parents actually end up germinating. Those that do have a chance to perpetuate the family line. However, simply reaching the germination stage isn’t the end of the race.

A tiny seedling still has to compete with any nearby plants for food, water, and sunlight. Only a small minority of prairie plant seedlings make it to maturity and create their own flowers and seeds. They either wither and die in the face of more competitive neighbors or get eaten by herbivores looking for fresh new growth to nibble on.

Tall thistle (Cirsium altissimum)
Sensitive briar (Mimosa quadrivalvus)
Ironweed (Vernonia baldwinii)

Despite the odds, of course, some seeds do manage to germinate and then become parents themselves. We’ve got abundant evidence of those successes all around us. It’s easy, though, to take those winners for granted. Spare a thought for all those who didn’t make it!I’m cheering on all the little germinating plants in the prairie right now. They’ve already survived a ton of obstacles, but they still have a lot to overcome.

I often wish seeds good luck when I see them, too (usually silently, especially if other people are around). While most seeds fail to become plants, each one of them plays a vital role in the prairie ecosystem. Animals and other organisms have to eat, after all, and seeds help keep lots of other community members alive.

Apart from everything else, seeds and the structures that help carry them into the world are simply beautiful. I’m incredibly appreciative of the diversity and aesthetic elegance of prairie seeds and I’ve spent a lot of joyful hours photographing them. I just try not to dwell too much on their individual survival chances…

Hubbard Fellowship Blog- Sprouts

This post was written by Evan Barrientos, one of our Hubbard Fellows.  Evan is a talented writer and photographer and I encourage you to check out his personal blog. If you would like to see more of his photographs, you can follow him on Facebook.

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Woolly Plantain (Plantago patagonica) sprouting form a pocket gopher mound.

Watching plants resprout this spring has been really interesting for me. Spending time with Chris Helzer has made me appreciate the small details of prairies, particularly plant diversity and distribution. Through him I’ve learned to read a prairie’s history of management and disturbance even in early spring…and appreciate its minute aesthetics! On March 21 I was taking a sunset walk (looking down rather than at the sky) when I noticed several attractive sprouts growing on the sandy mounds created by pocket gophers as they dig tunnels. I remembered reading how burrowing animals play an important role in plant germination. By providing patches of bare soil, these rodents give seeds an open place to spread their roots and leaves with much less competition from other plants. It was neat to witness this happening for myself!

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On that walk I also found my first flower of the year! Carpeting just a small segment of our trail as it runs through the sandhills were dozens of tiny Sun Sedges (Carex heliophilis) already in bloom. If you weren’t looking for them, you might not even realize what they were. Their flowers were quite small, but in March their waving yellow petals were like thousands of little victory flags. Two nights later, a sudden snowstorm roared through Nebraska. I was eager to see if the delicate flowers had survived, so the next morning I was trekking back to them before sunrise. To my delight, the flowers were still there, poking through the snow. I got on my belly and started photographing. I wanted an image that represented spring’s triumph over winter. As the sun crested the hill it bathed the sedges’ petals in gold. Like dozens of tiny torches, the sedges proclaimed that spring had indeed won.

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Sun Sedge (Carex heliophilis) blossoming in snow.