January Thaw

Saturday, January 12, 2012

What a contrast! Last Saturday we were bundled up hiking in snow, and today we removed several layers as the temperature climbed to 65 degrees. This warm southern air is bringing lots of moisture with it, and will be followed by what the weather forecasters like to call an “arctic blast”. Sunday looks very wet, so today we headed with a friend to Dawes Arboretum in Newark.

We have hiked the trails through the prairie and wetland areas at Dawes but we had never walked through the more central areas, so today we took the loop trail from the visitor’s center to the lake, and back to our car. It went through both the formal gardens and the woodland. This was anything but a dismal winter hike! Right by the visitor's center we found this lovely Lenten Rose or Hellebore just about to bloom:

Despite its name, it is not closely related to roses, and the Hellebores are native to Europe. They certainly add a lot of beauty to gardens very early in the year, when little else is in bloom. 

The arboretum has an amazing array of woody plants from all over the world, roughly organized by botanical family. My favorite area was the holly collection, one of the largest in the world. A large flock of American Robins was feasting on the berries. The familiar American Holly was featured prominently:

The deciduous Winterberry Holly was gorgeous:

Here is a black-berried holly called Inkberry, which is native to much of eastern North America:

This yellow-berried holly cultivar was also stunning:

As we walked the trail we were surprised to see a few dandelions in bloom, taking advantage of the warm day and a bit of sunshine. These cheery yellow flowers are excellent nectar sources for insects:

We were in for a couple of surprises as we hiked through the woodland, which is dominated by beech trees both large and small:

The friend that we were hiking with showed us a tent caterpillar egg case on a cherry tree, a preview of things to come in the spring. Soon our friend noticed this moth cocoon hanging on a spicebush twig, and immediately identified it as a Promethea Moth, which is also known as Spicebush Silkmoth: 

How cool is that? This moth caterpillar has surrounded itself with leaves, and cemented the capsule to the spicebush twig. The round buds that are visible are the spicebush's flower buds; in the fall this small tree will have bright red fruits that are eagerly consumed by a variety of birds. Spicebush is one of the Promethea Moth's preferred caterpillar food plants. Take a look at the gorgeous adult Promethea Moth at this link. 

A little further on we had our biggest surprise for a January hike: a butterfly! A  mourning cloak, a bit tattered but still readily identifiable, flew past us twice and we were pretty speechless! Mourning cloaks are one of the few butterflies that overwinter as adults in Ohio; they find crevices to shelter themselves and their physiology keeps them from freezing. They basically hibernate, but it is not unusual for them to fly on a warm day. January is certainly too early to expect them though!

Robins were active in the woods, turning over leaves looking for insects. At this time of year their diet is mostly berries, but on a warm day like this a few invertebrates are active and provide some protein:

Notice how well this robin blends into its surroundings!

Speaking of active insects, here is a mid-day look at the beehive at the Dawes visitor center:

I can't imagine that they were getting much nectar, but maybe they visited some dandelions!

After lunch we headed to Lobdell Reserve, a park near Alexandria, and did another loop hike. Most of the snow was melted here, but there were a few patches remaining:

This made me think of Jim McCormac's post a few days ago about "snow fleas" over at Ohio Birds and Biodiversity. These are tiny critters called springtails or Collembola, which are now classified as "hexapods" although they used to be considered insects. They occur in tremendous numbers in the soil, and especially on sunny days they come out on top of the snow and look like little specks of pepper. They are just a few millimeters long at the most, but they can travel several inches in one jump.

I was wishing that I had known about these critters last week when we had so much snow, but I decided it was worth looking at the small snow patches that remained today. I looked at lots of patches, and saw lots of little black specks but they didn't move and were probably just dirt! Finally, down on my hands and knees, I checked out a patch that did indeed have springtails! They weren't present in huge numbers, maybe because it wasn't very sunny, but they were pretty cool nonetheless:

Now that picture might not generate much excitement, and this guy was only about 2 millimeters long, but boy could it ever jump! And it is pretty cool that this animal would be so active on the snow in January. There are hundreds of species of springtails in North America, and this looks quite different from the ones that Jim photographed--and I won't hazard a guess as to which one it might be.

We also saw a fairly fresh crayfish burrow:

These crustaceans bring up balls of dirt and deposit them on the surface. Burrowing crayfish are semi-aquatic and their burrows can be quite deep, eventually reaching water-saturated soil where their gills can stay moist.

Just as we were pulling out of the parking lot Bill heard something (other than road noise and the target practice taking place nearby) and we all got out to listen right by this small, partially frozen wetland:

It was a chorus frog! Their call sounds like a finger being drawn across a comb. 

We have learned to expect the unexpected on these winter walks!