More Milkweed Near Grassy Glade

Molly and Joe both carried butterfly nets all day, hoping to be able to tag an adult monarch. This Lorquin’s admiral was the only butterfly to make contact with a net. It must have found something tasty on the net and joined us while we ate lunch on the banks of Coal Creek.

On June 15, Molly Juillerat (botanist but now deputy ranger at the Middle Fork District), Joe Doerr (wildlife biologist for the Willamette National Forest), and I went back to Rigdon to do some more exploring. First, we headed out to see the purple milkweed (Asclepias cordifolia) at Coal Creek Bluff. Neither Molly nor Joe had been there before, so I’d been hoping to take them there for some time. We took a relatively short spin around the slope, stopping to check on the milkweed. There was no sign of eggs or caterpillars yet, so I’m still not certain if the monarchs know about this small population. Although the slope was pretty dry, there were plenty of nectar plants to be had if any monarchs did show up. The milkweed was in fading bloom, but fresh northern buckwheat (Eriogonum compositum), Oregon sunshine (Eriophyllum lanatum), bluefield gilia (Gilia capitata), and elegant cluster-lily (Brodiaea elegans) added some color to the mostly brown slope.

In a very similar photo to one I took on my last outing, five juniper (aka cedar) hairstreaks and two beetles were sharing lunch on the same northern buckwheat inflorescence. This really is a superb nectar plant, and it is also used by caterpillars of some species (though not by the hairstreaks, who, as their names suggest, use cedars and junipers).

Who could have laid these pearly eggs on the milkweed?

Most of the day was spent at Grassy Glade. I was really hoping the male monarch I had seen a few days before (see Butterflies Galore at Grassy Glade) would still be there, but while we saw many other butterflies, he never appeared. We didn’t find any monarch eggs or caterpillars here either. Joe did spot a cluster of really shiny, spherical eggs on the milkweed. I have no idea who might have laid them, but they were quite beautiful.

Joe heading down what he dubbed “Rocky Glade”.

The milkweed patch at the bottom of Rocky Glade.

Joe was really interested in checking out some of the openings just south of the main meadow that none of us had been to yet. He led us down through the open woods past a few small grassy spots before we popped out at the top of a very steep, rocky slope with a lovely view of the Staley Creek drainage. This was much better than what I was expecting, and we were thrilled to find such an interesting spot. Like nearby “Rabbitbrush Ridge,” there was quite a bit of buckbrush (Ceanothus cuneatus) here, perhaps a sign that this area had burned at some point. As we peered over the rocks to the slope below, we were thrilled to see a number of milkweed plants! We carefully made our way down the rocks to get a better look at the population. We looked unsuccessfully for eggs and did a somewhat informal count of the plants. Our total came to about 60 plants, including 46 with flowers. While not a huge population, it seemed quite healthy, and we probably missed some smaller plants as it wasn’t the easiest place to traverse.

Molly’s dog, Ruby, helping us counting milkweed plants.

Back up at the population by the road, we looked again for the monarch, but he still didn’t show up. Joe wanted to take a look at Big Pine Opening, so we made one last stop before going home. Molly, Ruby, and I were taking our time going up the steep slope to that milkweed population. By the time we met Joe at the top, he told us rather disappointingly that he had seen a monarch sitting on some milkweed, but in his excitement to try to net and tag it, he’d scared it away before he’d even determined whether it was a male or female. Well, at least we knew it had been there. And we did find around 7 eggs on these plants, so we knew a female had been there. Some were under the leaves, where we expected them to be, but several were on top of the leaves, and a couple were even laid on the immature seed pods. Why there were so few eggs, we don’t know. Perhaps they’d been eaten by other insects. Or maybe an overeager biologist had scared the butterfly away before she finished laying all her eggs!

One perfect monarch egg laid on the developing seed pod of purple milkweed at Big Pine Opening. I love the abstract nature of this photo. If you didn’t know it was a milkweed plant, you might think it was something from a science fiction movie.

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