Tryon Creek Naturalist Notes

Euonymous occidentalis or Western Wahoo

You might see a late fruiting, unfamiliar plant along the trails of Tryon Creek known as Western Wahoo.  Western wahoo, also known as burning bush is a member of the Celastraceae or Staff-tree family.  It’s most often noted by its opposite (deciduous), finely serrate leaves and pink/red pod-like fruit, which I happened to mistake for flowers at first glance. 

You may be asking yourself, “what is the fruit all about?” I missed the wahoo flowering since the flowers tend to be hanging underneath the foliage on thin peduncles.  Peduncles are a scientific term for stems occuring on flower clusters.  When ripe, the seeds are covered by a reddish-orange aril (leathery capsule).  Pojar describes the fruit to be similar in construction to a cashew.  I may have to take a look at the next fruiting specimen I find under the dissecting scope to learn exactly what that means.

To confuse you even further, this plant is classified as a “sensitive” plant by the federal government which means it is not yet considered “rare”, “threatenend” or “endangered” but could soon be considered for one of the latter terms.  What I do know, is that you would never want to say any of this in front of a Western wahoo plant, for its feelings are very easily hurt. 

 How wonderful that this seldom seen plant has chosen Tryon Creek as its home.  Take an opportunity to stop and admire it the next time you are walking in the park.

Distribution map of Western wahoo from Oregon Flora Atlas

At a recent Story & Stroll focused on spiders and their webs, a group of pre-schoolers and I counted 38 spider webs along our short Trillum trail, aware that we must have missed many more. By far the stars of the show were the intricate webs of the orb weavers, a group of spiders in the Araneidae family. These are the large spiraling webs of concentric circles made famous in E.B. White’s Charlotte’s Web, and like Charlotte it is the female orb weaver who spins the big showy webs. In fact, the diminutive male is rarely seen except when he spins a smaller scale orb web into an edge of the female’s.
Orb webs contain non-sticky radiating support lines- like the spokes of a bicycle wheel- that attach the web between two trees or other surfaces, and sticky circling lines between them. These lines are often so perfectly parallel that it seems the spiders must have built in rulers. Yet as large and complex as these webs may be, they are usually rebuilt daily. Once built, some orb weavers hang motionless upside down in the center of the web like a bulls-eye, while others will lay in wait on the edge of the web. When finished with their webs for the day, these conscientious spiders may consume their used webs to conserve nutrients. Reusing and recycling at its best!
The next time you take a woodland stroll you too can look for these master architects, especially visible on drier, sun-dappled days. Fall is the best time to see these insect eaters, as you may have noticed if you too find yourself walking into spider silk regularly these days. Despite what it may seem, there aren’t more spiders around this time of year, but spring’s tiny spiderlings have been eating and growing and are finally at their largest, needing wider spaces for their larger webs. Unfortunately for those arachnophobs out there, those wider spaces often turn out to be human pathways. However if you are lucky enough to have an orb weaver who has made her home in a more spider-appropriate location such as outside a window, take some time to watch your pest-eating neighbor. You too might come to appreciate the fascinating world of the orb weaver.