Behind the Fence

On the north side of an impenetrable white vinyl fence, unseen and likely forgotten by those who built the fence, a little micro-habitat of opportunists thrives just out of reach of the trailside mower. 

Horseweeds, sowthistles, fleabane, dock, amaranth, a spiky flatsedge, and an enterprising grapevine are just a smattering of the dozens of plants making a community in this shady, 65-foot span. Even late in the season, into October, there were still some flowers available on the horseweeds and fleabane to bring an assortment of tiny pollinators, including a stunningly-patterned moth. 

Spotted Beet Webworm Moth

(Hymenia perspectalis, tentative)

Earlier in the season, this scrappy little patch would have barely merited a glance, when just opposite the Greenway was glowing with big, beautiful flowers everywhere. But squeezing out the last bits of summer, before the last flowers fade and the last insects disappear for the long winter months, it's a low-expectation oasis. 

Life happens when we give it a chance. 

 

Consider the Spider

Orchard Orbweaver

"Once you begin watching spiders, you haven't time for much else."

- E.B. White

Consider the spider. Eight legs, eight eyes, silken webs. When welcomed into the home, may go by the name of Charlotte or Boris. Everyone has an idea of what "spider" means. 

Bowl and Doily Spider (tentative)

But do we? Records on iNaturalist show more than 60 species of spider identified in Iowa City alone; though they share a similar general body shape, there is an astonishing variety of features that can be seen, with different groups adapted to different lifestyles. They are generally divided into two categories: those that spin webs, and those that hunt their prey. 

Within those two categories there are dozens of other specializations. Some species of web-building spiders may create the typical two-dimensional spiraling orb between vertical branches or posts, like the beautiful jewel-toned Orchard Orbweaver; others make those cobwebs that add atmosphere to the corners of your basement, or they construct elaborate sheets (or even "bowls and doilies")  held aloft on grass stems.

Hunting spiders are further categorized as wolf spiders, jumping spiders, crab spiders, and several others. They may still produce silk, as a dragline to help them get around, for example, but they don't create webs to trap their prey. Nimble jumping spiders actively hunt with the help of their excellent eyesight, while many crab spiders rely on camouflage to lurk in wait for a passing insect.

They are beautiful, beguiling little bits of life that share our yards, and sometimes our homes. They feature in our stories and our songs, and are worth spending time getting to know. 

Sources/Additional Reading:

• Common Spiders in and Around Homes - ISU Extension (PDF)
• Spiders - University of Minnesota Extension

A pair of domestic spiders(?) found around the house:

Bold Jumping Spider

Common Cellar Spider

The Not-so-subtle Senna

Yellow, yellow flowers everywhere. Walking a familiar part of the trail, my eyes scan the usual floral sights of late July: the Silphium brothers Cup Plant (big brother) and Rosinweed (little brother); inspecting the Gray-headed Coneflowers for Camouflaged Loopers...hello, what's this?

My brain, seeing the shape and color of the bushy yellow inflorescence, quickly said "Showy Goldenrod, nothing unusual, move along" followed immediately by "isn't it a little early for goldenrod?" and directing the eyes back for a closer look. 

Bees and ants visiting
senna flowers.

Despite the initial vague resemblance...definitely not a goldenrod. For one thing, the leaves are compound, with tidy paired leaflets. And the yellow flowers comprising the showy inflorescence were big and blowsy, with many dark anthers projecting from the loosely open petals. A senna! Has that been there all these years and I've just never noticed it before now? It's hardly a subtle plant.

There are two similar species of senna in our area, which can be tricky to tell apart: Maryland Senna (Senna marilandica) and American or Wild Senna (Senna hebecarpa). Some points mentioned to help identify are the hairiness of the style (longer on Wild Senna) and the behavior of the seedpods. (I am not confident in our senna here so I will just call it a senna.) 

Knob-like nectaries are situated
at the base of leaves.

They are members of the legume family and are native to the eastern U.S., with Maryland Senna having a slightly wider range, reaching Nebraska and points south. All those stamens (ten in total) provide pollen to bumble bees (and many other pollinators). 

If you look closely at the base of the leaves, you'll find a curious rounded knob: an extrafloral nectary, which makes sweet nectar available to ants, wasps, ladybird beetles, and other insects that may take advantage of the nourishment, possibly providing protective services to the plant in exchange. (Another yellow-flowered native legume, Partridge Pea, similarly provides nectar in the form of little pots at the base of the leaves.)

It's a beautiful plant, and provides a lot of interest not only to wildlife but human observers too. I'll definitely be keeping an eye out for it in the future. 

Really...not very subtle.

Sources/Additional Reading:

• Plants For Pollinators: Wild Senna
• ‘Will Work for Food’ – Extrafloral Nectaries
• USDA Plant Fact Sheet: Wild Senna
• Illinois Wildflowers: Wild Senna and Maryland Senna
• BONAP
• North Carolina Extension: Senna marilandica
• Friends of the Wildflower Garden: Wild Senna