Exotic Beauty

Early in my career, I felt pretty strongly that only native plants should be in the prairies I managed.  Pretty quickly, I realized I didn’t have enough time to eradicate the worst invasive plants from our sites, let alone worry about some of the more innocuous non-native plants.  In fact, I found some of those non-native plants could be pretty valuable (e.g., dandelions and their early season resources for pollinators).

I began to take a much more pragmatic approach to managing plant communities, working to suppress species that tended to form monocultures or become dominant enough to suppress the diversity of plant communities.  Some of those dominant/aggressive species included non-native invasive grasses and woody plants, but also some native species such as big bluestem, eastern redcedar, smooth sumac, and rough-leaved dogwood.  A plant’s status as native or not became less important than how it affected the diversity and function of the plant community it was part of.

A goatsbeard flower opening at sunrise.  Niobrara Valley Preserve.

One non-native plant I’ve always gotten along with pretty well is goatsbeard, aka western salsify (Tragopogon dubius).  Sure, it wasn’t here before European settlement, but it isn’t aggressive and has simply added itself to the plant diversity of many of our prairies.  Also, it’s really pretty (though so are many nasty invasive plants).  Both when it flowers and when it goes to seed, goatsbeard makes an attractive photography subject.

It’s fun to stick a macro lens into a goatsbeard seedhead, which resembles a fist-sized dandelion head, and try to create interesting abstract images.  Goatsbeard seedheads were one of my favorite subjects when I first started playing with close-up photography about 25 years ago, and they still attract me today.  I never get tired of looking at those big fuzzy parachute-style appendages attached to the seeds.

Becoming less of a snob about the native status of plants has made my life a little less stressful.  There are plenty of plant species that require serious attention in order to maintain healthy, diverse, and resilient prairies.  Worrying about whether a plant was here 200 years ago is the least of my worries.  Now when I walk around a grassland, I’m comfortable greeting species like dandelions, goatsbeard, and lamb’s quarters as friends (while still trying to eliminate problematic non-natives such as crown vetch, Siberian elm, and Canada thistle).

Photo of the Week – May 5, 2017

During the last week, I’ve been lucky enough to find and photograph two different wolf spiders, so I figured I should probably dedicate a short blog post to them.  The first wolf spider I found was a cute little bugger out in the prairie the other day.  I was out looking for monarch eggs and caterpillars and saw the spider scurry between clumps of vegetation.  Since I had my camera in hand, I stopped and had a visit.  The second spider was in our basement and was considerably bigger (2 inches in diameter with legs).  I took it outside where it could be happier, and photographed it before letting it roam freely in our garden.

This big beautiful wolf spider was in our basement before I put it back outside.

There are a lot of big fuzzy spiders that resemble wolf spiders, but true wolf spiders have a characteristic eye pattern that sets them apart.  If you look at the above photo, you can see that there are two large eyes above a straight row of four smaller eyes.  If you look even closer, you might be able to see two additional eyes behind the big ones that point up and to the sides.  You can see those last two eyes more clearly in the photo below.  The layout of those eight eyes is unique to wolf spiders, so if you ever wonder if a big fuzzy spider is a wolf spider, just look it in the eyes and you’ll know.

In this photo, it’s easier to see the wolf spider’s non-forward facing eyes.

There are more than 2,000 species of wolf spiders across the world, and they are a fascinating group of creatures.  Although they are free-roaming spiders (they don’t create a web and hang out on it), they still use ambush as their primary means of hunting.  They’ll usually sit quietly and wait for prospective prey to come within striking range. Wolf spiders hunt mostly at night, and their eyes are well-adapted for seeing in low light.  However, wolf spiders are also very adept at sensing and using vibrations to identify their prey.  Their hairy legs aren’t just for looks; they also act as part of a complex system of vibration sensors.  Wolf spiders can distinguish between patterns of wing beats or footsteps to help them determine what kind of creature is coming near.

This small wolf spider was out in the prairie while I was looking for monarch caterpillars.  Its body and legs were about a half inch in diameter.  Note the distinctive eye pattern that characterizes it as a wolf spider and the different kinds of hairs on the legs.

My daughter made me proud the other day by telling me she was able to impress her college friends with some of my favorite spider trivia: the reason spider legs always curl up when they die.  Spiders have flexor muscles on their legs (muscles that pull the legs toward their bodies) but not extensor muscles to push them back out again.  Instead, they use hydraulic pressure to extend their legs.  A fluid called hemolymph is pushed into the legs, counteracting the flexor muscle pressure enough to extend the legs.  It sounds like a cumbersome system, but if you’ve ever seen spiders run and jump, it’s clear that it works very well.  When a spider dies, it no longer has hydraulic pressure in its legs to counteract the flexor muscles so the legs naturally curl up toward the body.

Don’t you just love spiders?  Of course you do.

Here’s the big female one more time, just before she turned away to go explore our garden.