New Gallery of Seed Scans

Delphiniums have irregular seeds. Those of the very tall D. glaucum are much larger and a different shape than those from a population of what appear to be hybrid D. nuttallianum x menziesii from Balm Mountain (inset). It will be interesting to see if these last seeds differ from their purebred parents. The ruler increments are millimeters.
For many years, I’ve collected seeds of our native plants, both for my personal use and to share with the NARGS seed exchange, so others could grow some of our beautiful rock plants. After I bought a microscope, I discovered how much variety there is among seeds, even in plants of the same genus. In fact, some species are distinguished by their seeds. This can be hard to do with the naked eye, but it is well worth looking at small seeds under a handlens or microscope.

The fine mesh covering of Romanzoffia thompsonii seeds, similar to that on Castilleja seeds, was a surprise to me.
I set up a system so that I can photograph through my microscope, but, unfortunately, I’m not really satisfied with the results yet. Several years ago, I bought a scanner to replace my old one, which was no longer compatible with my then-new computer. Since I wasn’t doing any artwork at the time, however, I never got around to setting it up. Recently I decided I needed to scan drawings and some old artwork, so I finally set it up. Except for a few that I actually got around to sowing, my collection of seeds has been sitting around for ages waiting for me to figure out how to photograph them. This new scanner is capable of very high resolution in order to scan slides. It occurred to me it might work well for seeds, so I decided to give it a try.

These are seeds of an unidentified rockcress (Boechera sp.) on Eagle Creek Rd. 5883 near Hell’s Half Acre. Not all rockcress have wings on the seeds, so this is an important feature to note.
Starting with the larger seeds, I poured some out directly onto the scanner plate. I was thrilled with the results. The smallest seeds—things like saxifrages and Heuchera—are still a bit blurry, but most look quite good. They are nowhere near as detailed as an electron micrograph image, but they are certainly decent enough to use for most identification purposes. And even if one is not interesting in identifying plants by their seeds, they are quite fascinating in their variety and detail. Some I would even say are quite beautiful. I spent several days scanning everything I had available. This fall, I will have to be on the lookout for species I haven’t collected before or haven’t wanted to try to grow, just to see what they look like. I’ll try to add many more to the gallery in the future, but for now, click here for the Seed Gallery to take a look at some of our native seeds. While most are from the Western Cascades, I have included a few from some of my other hikes, so you can see the variety within the genera.
What sprung to my mind was: function of reticulation? Intuitively I thought increased surface area for water absorption. Google search results didn’t support or deny, but I did find that when seed matures and dries the resulting concavities are the shape of underlying cells. The seeds with deeper reticulation have more pectin (swells when wet, holds moisture for germination) under the seed coat….
I’m not making progress on my to do list. Look! There’s a hermit thrush in the yard!
Images much appreciated-Lori
Cool :)