Sunday, March 27, 2011

Back at the Burn

Okay - so here we are, the second half of my Saturday Morning Walk, and we are once more back at last Sunday's burn.

 One of the really exciting things about a burn is just how quickly the vegetation takes over.  There are several reasons for this: the sun can now reach the soil to heat it up (thus germinating the seeds hidden therein), and the blackened soil just speeds this process up; many native seeds in prairie habitats evolved with fire, and thus often need fire to prep them for germination (for some this involves fire melting a resinous coating that otherwise keeps the seed from the light and moisture that would stimulate germination for a regular seed); there is no struggle to get light (in an unburned field, the old dead vegetation creates a barrier that may hinder rapid growth).

So, I got down on my belly, on the charred ground, and snooped around in search of a new green sprout.  And there it was!

I was actually quite surprised to see this sprout.  All week the temps have been below freezing - both day and night.  Not conditions that really trigger growth.  This just goes to prove that the sunlight is heating up the dark ground just enough to make things grow, even if only very slowly.

I really should come back once a week and set up my camera at the same place each time and take a shot - see the greening over time.

ANYway - continuing through the burn, I saw a small pile of bones:

I looked around, for I had heard that the Tuesday Morning Group had found old coyote den holes nearby.
I had a lovely view of this tree against the springtime sky.  Doesn't this shot just sum up the prairie?

And there, hard by the tree, a pile of white sand caught my eye.  This looked highly suspicious.  What would cause a pile of white sand in an otherwise blackened and charred landscape?

AH-ha!  It was the aforementioned coyote den!  The hole to the den is to the left side, with the sand dug out from it piled up around the right side.

Nicely placed on top of the pile of sand was a perfect pile of scats.  Definitely coyote.  They are white, though.  Hm.  Knowing that there are no snowshoe hares around here, this meant that these were probably older scats.  Older because they are white with age, or older than the fire and they are ashen from the blaze.  Whatever the reason, they aren't terribly fresh.

Here you can see the placement of the scats next to the den entrance.  Notice also the pieces of vegetation across the entrance.  One of the Tuesday Morning Group did this as a test to see if the den was active.  If it is, then the vegetation would be moved aside.  If the vegetation remains in place, then the coyotes are no longer here.  

Two more entrances were located just downslope from the first.  One still had vegetation across the opening, but the other did not.  Hm...perhaps the den is not completely abandoned.

And here you can see all three entrances, forming a nice little triangle!

The coyote den wasn't he only source of holes.  Here we have some much smaller tunnels going below ground.  Voles?  Mice?

And more greenery showed up as I continued to look!  This thistle is doing quite well.

As is this mullein.  Mullein has very thick and fuzzy leaves to begin with, which makes it well-suited for growing early in the season when cold temperatures are very likely.  Thus protected, it doesn't feel the bite of winter's cold.

Ah. Now here is an important view of the prairie, a view that demonstrates why native grasses are so important to these ecosystems.  Here is a view of the restored portion of our prairie:

...and a view of the prairie where non-native plants dominate:

Do you see the difference?

Once again, the native portion:

...and the non-native (conveniently side-by-side):

Here is the answer:

Clumps of native grasses.  Looking at the restored area, you see lots of charred bumps - these are the native grasses, which will resprout once things warm up a bit.  Native grasses grow in clumps that are dispersed across the open ground.  Non-native grasses tend to grow in mats - solid mats that don't clump up. 

This is an important concept.  If you have native grasses, then there is space in between them for other native plants, like the many wildflowers and other forbs that call prairies home, to grow.  Additionally, these spaces give wildlife (small wildlife) places to move, and places to hide.  And, when winter comes around, native grasses remain tall, providing additional shelter (and food) for small birds.  Non-native grasses tend to just smoosh down under the weight of winter's snows.  This might provide some nice protection for small mammals traveling below the surface of the snow, or it might not - maybe it hinders their travel by being so compact.  Hm.  Something to ponder.

 Well, the morning was moving along toward noon, and I had plenty of work to do back in the office, so I headed back.  Along the way, though, I did find some more proof that spring is in the offing:

Woodland flowers are sending up their leaves, soon to be followed by stems and flowers.  Woodland flowers bloom before the trees fully put out their leaves, taking advantage of the sunlight while they can.

A Morning Walk

 Saturday morning dawned sunny and bright...although it remained below freezing.  When I arrived at work, I decided it was imperative that I work on learning the property.  After all, I've been here three months now, so it is about time I became familiar with the place I was hired to interpret.

So, camera in hand, I hit the frosty trails.

 Frosty branches in wetland.

 Frosty deer scats on boardwalk.

 Very frosty railing along boardwalk.

 Frosty vegetation on the ground.

Frosty leaf.

This tree trunk fascinates me every time I walk by.  Three holes, each atop the last.  Why?  What caused the crease in which these holes reside?  There must've been some sort of damage done to this tree, which caused the crease (the tree's continual growth giving the original injury rounded sides).  This damage must have in turn attracted insects, which took up residence inside.  And then the insects attracted birds, which excavated the holes.

Not all strange growths on trees are due to nefarious causes.  Burls, like the one seen below, still confound scientists.  Some may be caused by external agents (similar to galls), but not all can be attributed to specific causes.  Whatever their source, they don't seem to harm the trees on which they grow, and they are often sought by woodworkers, for burls make spectacular bowls, with their swirled grains and tight growth patterns.

Now, here's an impressive specimen of poison ivy.  Sadly, but with good reason, most people despise poison ivy, for it harbors an oil to which most of us are allergic (see my post from last summer about my own run-in with the stuff). 

Still, it is a native plant, growing both in vine and ground-cover form, that produces white berries that are important to many bird species as a source of food.  In other words, PI is an important part of the native landscape; we humans just need to learn how to live with it!

My primary goal on this morning's walk was to cover the perimeter trail(s) - I wanted to see parts of the property I hadn't seen yet.  Much of the property is either hardwood forest or open field/prairie.  There is, however, a nice patch of conifers out along the northeastern perimeter.

The winged wahoo (I just love that name) is quite prevalent in several parts of the property.  A highly invasive non-native, it is, never the less, kind of attractive, especially when viewed through a macro lens.

I was soon nearing the edge of our property. 

Definite signs of previous human use soon became apparent.

And then I found myself facing one of the neighboring farms. 

I turned around and retraced my steps, and before long I was at a lovely vernal pool.  These temporary habitats form in the spring (vernal) from the melt waters of winter's snows and the added moisture of spring rains.  Last week, they were full of frog song.  This week, they have been pretty silent, thanks to the return of below-freezing temperatures.  Still, I did hear a lone chorus frog calling a couple times during this walk.

Previously I posted a video of this glacial pond, recording those very frog songs.  Today I found myself on the far side of the pond.  I had no idea a trail went along this side.  There's even a bench here, where those who are so inclined can sit quietly and enjoy the sights and sounds of this pond.

Today, however, things were a bit frosty for sitting for any length of time.

Following the trail just a little bit further, I found myself back at the burn.  It was now almost a week since we burned, and I was curious to see if there was any new growth yet.  I suspected not, since the weather had turned chilly - not conducive to seed germination.

My trip through the burn will be posted next.  Stay tuned.

Thursday, March 24, 2011

Shameless Advertising

I've just started another blog.  This one is strictly work-related.  It is called Dirt Time at Dahlem and it's all about the Dahlem Center.  I plan to have all members of the staff available to write posts for it.  So, stop on over and learn about the Dahlem Center/Conservancy.  You can read about our programs, what's blooming, what birds are flying through, and in general what is happening!

Sunday, March 20, 2011

And How Did YOU Spend the Spring Equinox?

The call came in this morning - today's the day - 1:00.  We were going to burn the prairie.

Fire used to be a natural part of the prairie landscape.  Before people dotted the plains, prairie fires were probably ignited by lightning strikes.  The native peoples learned that fire renewed the prairies, and soon man-made fires were used to keep the trees at bay and to help renew the soils and fields.

As Europeans took over the continent, and their subsequent development, fire became the enemy of the people, so it was suppressed at every opportunity.  It is only in the last few decades that we have learned a hard lesson:  fire is important (vital) to maintaining many natural ecosystems.

So, as part of our land stewardship program at the Dahlem Conservancy, we hold prescription burns on our property to renew and maintain our patches of prairie.  Gary told me this week that he was planning to schedule one sometime in the next few weeks. On Friday he said it might be sooner rather than later.  Suddenly, yesterday we hear it might be today.  And, at 8:30/9:00 this morning, the call came.

Of course, I couldn't wait to go and play.  Years ago, when I worked in NJ, I got to participate in a prescribed burn.  I was eager to be a part of one again - even if it was just on the sidelines taking photos.

Soon the official Burn Crew arrived and began unloading gear:  driptorches (full of fuel - used to ignite the fire)...

 ...Indian tanks (these are the water packs used to put out stray flames and sparks)...
...and radios, radio harnesses, fire resistant clothing, hardhats, etc.  Hooray!  We were asked if any of us wanted to  I jumped at the opportunity and donned a yellow shirt, radio and harness, hardhat and indian tank.

And we drove off to the site.

Gary reviewed the map with Dave so everyone knew what was actually supposed to be burned.

Dave, the burn leader, explained that we were going to light a back burn on the downwind side of the site.  The trail would act as a natural barrier, and the fire would burn into the field, upwind.  The wind would work in our favor, helping to keep the fire under control.

His crew lit a small test patch just to make sure.

And we were off!

Most of the staff who participated were strictly there to keep the stray flames from getting out of control - we had our Indian tanks on our backs (40-60 pounds of water) and hand-pumped nozzles to squirt errant sparks.

Once a good buffer of 20-30 feet was burned, we didn't have to worry too much about sparks jumping the trail.

Sometimes, when the fire hit a good source of fuel (lots of dead vegetation), or when the wind gusted, we'd get some pretty robust burning.

Our crew went around the northern edge of the field, while the other crew headed around the southern edge.

Here we've turned the corner of the patch we were burning and Andy started to set the head fire - the one that would burn with the wind and into the back burn we'd just done. 

 There it goes!

In this pan you can see "our" fire creeping across the field toward "their" fire.  Soon the two would meet in the middle...

...and whoosh!

The burned landscape:

Doing the burn on a chilly day put odds in our favor that snakes would be below ground - a concern here because we have massasauga rattlesnakes, which are protected.  The only wildlife I saw was a vole making a hasty retreat into a woodchuck hole, and some birds flying overhead.

After the fire burned itself out in the first patch, the crew walked over to check out a second, smaller patch that Gary wanted torched as well.  It was kind of like watching astronauts crossing the moon.

 The second patch was significantly smaller, but also covered with last year's leaves.  Dave wanted a line blown clear of leaves before we started, just to make doing the back burn a little easier and to cut down on the chances of some sparks setting the wrong side alight.

We refilled our tanks with water.

And soon we were off again!  The fire burned pretty hot in here, but the area also resisted burning.  The fellows with the drip cans had to continually lay down lines of flame. Later, Gary explained that the patches that resisted the fire were spotted knapweed, an invasive species.  In order to affect these plants with fire, they have to be burned later in the season when their rosettes are above ground.

Someone is in for a rude awakening! (Man - I went to bed in a field, and today I wake up to find the whole landscape has changed!)

It was a good thing things were coming to an end, because as the last flames were dying out, it started to sleet...then rain.  It was 37*F, and with the fire mostly out, things started to get chilly.  We loaded the gear back on the various vehicles, sat on the wet seats, and headed back to the farm, putting out any smoldering logs, stumps, and clumps of vegetation along the way.

If the weather weren't so miserable out now, I'd be tempted to go back to the field tonight.  It has been my experience that freshly-burned fields are great for owling.  The mice and voles have nowhere to hide, so it's easy pickings for the raptors.  Gary said that woodcocks also visit freshly-burned fields - must be the worms have nowhere to hide either!  Maybe some night later in the week, when the rain stops.

So, Happy Spring, y'all!