2010 RUNNING & TRAVEL ADVENTURES

 

   
 
Runtrails' Web Journal
 
Previous          Journal Topics by Date            Next
 

BRAZOS BEND STATE PARK, PART 3:
PLANT ZONES & DRAINING THE SWAMP

FRIDAY, MARCH 26

 
" . . . In places, a mature forest canopy reaches for the sky above the park. The trees
provide refueling stops for migratory birds and sanctuary for native wildlife species . . .
Wetlands of many kinds enhance species diversity at the park. Brazos Bend wetlands
include swamps, lakes, and marshes . . . Tall grass prairie once covered North'
America. Today little of it remains. But within the park, visitors still explore
small communities of native grasses that remind us of the grass prairies."
 
~ from the park's interpretive guide
 
 

I love the wide variety of trees and other plants at Brazos Bend! They are a result of the unique mix of eco-zones within the parkthe bottomland hardwood forests, wetlands, and upland tall grass prairies that I talked about in the last entry.

Here is a picture of a tactile relief map in the Nature Center that shows the relationship of these three eco-zones. Woodlands are green, marshes and wetlands are light blue, prairie and grasslands are tan, and water is medium blue:

The park entrance is to the left, campgrounds are the loops in the center, and the Brazos River is on the far right. Big Creek winds diagonally through the park and empties into the river at the lower right (SE) corner of the park. That's where the Red Buckeye Trail is located (most of the trails aren't shown on the relief map).

It was fun to pass through the various vegetative zones each time we drove, walked, ran, or biked through the park. Huge live oak trees dripping with Spanish moss here . . . marsh grasses with herons and ibis feeding over there . . . a field full of yellow buttercups nodding in the breeze up ahead . . .


This is my "Monet painting" shot of some aquatic grasses along Elm Lake.

It was also fun to watch the amazing transition of the leaves and flowers from early to late spring in the span of just four weeks. It makes we wonder what the park looks like in each of the four seasons.

Each day brought new surprises as we explored the park. My senses of awareness have been heightened all month! Come along and I'll show you some more of the park.

1. THE WOODLANDS

Changes in elevation of only a few feet mean significant changes in the woodlands at Brazos Bend State Park. It reminds me of the different eco-zones through which I've passed going up and down in the Appalachian and Rocky Mountain ranges, except the changes at Brazos Bend occur over much smaller increments in elevation.

The river bottomland and some areas along Big Creek support mixed hardwood vegetation including pecan, elm, sugar hackberry, various species of oaks, and numerous species of shrubs and vines. These are easily seen along the Red Buckeye Trail in the southeastern corner of the park where the elevations are lowest:

"Gallery" forests along the river, creek banks, and bayous are dominated by sycamore, cottonwood, and black willow trees. This is a view down to Big Creek in the NW corner of the park at the end of March when the creek level was lower:

The elevation is a little higher in the old "meander escarpment" of the river. These areas, characterized by magnificent moss-covered and vine-draped live oak woodlands, are especially noticeable near the park entrance, Hoots Hollow Trail, and 40-Acre Lake picnic area (below):

The oldest live oak in the park has been dated back to 1782 -- that's 228 years ago! There are several others that are about 200 years old.

The green fern-like plants growing on the limbs of this live oak are called Resurrection Plants:

They look brown when it's been dry for a while but perk right up and turn green when it rains.

2. THE WETLANDS

Brazos Bend State Park contains a lot of water, especially during the winter months -- so much, in fact, that this week the rangers have been draining the large swamps!

This ritual routinely occurs in March. This year the large area on either side of the entrance road (including Pilant Slough) was drained between Spring Break and Easter, the two heaviest weeks for visitors in the park. Pilant, 40-Acre, Creekfield, and Elm lakes all looked a few inches lower after four days, too.

There is some odor involved when the near-stagnant water is released and the muddy soil and waterlogged plants are suddenly exposed to the air, so the staff tries to minimize the impact on visitors and do the job when fewer visitors are there.

Here's a typical "before" picture of the swamp on the other side of the levee from Elm Lake:

For most of March the water was very close to the trail. On sunny days alligators often crawled up onto the grass right next to people walking by. In the photo above, there are two juvenile 'gators straddling logs in the water instead of lying in the grass; I circled them.

There are at least two reasons why the swamp is drained so the trees and other vegetation that get flooded each winter don't die -- they need some air and sunshine -- and to allow flooded trails like Pilant Slough and Live Oak to be opened up. The Pilant Slough, Bayou, and Sawmill trails were closed until a few days ago. They are still too wet for anything but foot traffic.


This low spot on the Pilant Slough Trail had just drained and was still muddy for about
fifteen feet when I walked the trail for the first time recently. It dried out in a couple days.

Two miles of Live Oak and three-plus miles of Creekwood trails are still impassable, even for foot traffic. We haven't ventured very far into either one of them because they are just too muddy.


Part of the Live Oak Trail that parallels the park entrance road: 
just drained and still too muddy to use when I took this picture.

Draining the swamp should open up all of these trails to pedestrians, cyclists, and equestrians in a few days unless there is heavy rain in April and May. I guess we'll have to return in the fall sometime (after it cools down from the summer heat) to see the trails we missed this month.

The drainage process took about four days this past week. The flood gates were opened (literally!) behind the Nature Center where Pilant Slough flows under a park road and runs about a quarter mile down into Big Creek. This picture shows the two drains that were opened; water is still flowing through the one on the left but is below the level of the pipe on the right:

The old water line indicates the water level has dropped about two feet.

This is what the water looked like on the other side of the road when it was gushing out:

Pretty cool, huh? (Stinky, too.) Before the flood gate was opened it was dry down there.

After only one or two days we could see the water level receding along the park entrance road ("The Longest Mile"), Pilant Slough Trail, and the swampy area on the south side of the Elm Lake levee. It was interesting to watch the changes each day and wonder just how many gallons of water were going through those pipes every hour! We're talking about a thousand acres -- or more -- of wetlands being drained.


Yum! New food sources!

After three or four days the water was down between one and two feet in different areas. Not only was more land exposed, the birds and other wildlife went crazy with additional food sources like worms and insects that were suddenly exposed (above).


Water covered this area next to the Elm Lake levee three days before I took this photo.
The soil is already drying out. Grasses will probably cover the area in a few weeks.

I had two surprises when the project was completed after four days of draining the swamp.

First, this bench near the intersection of the Elm Lake and Pilant Slough trails was finally high and dry (or it will be when the mud dries out). For several weeks I could see it from the Elm Lake Trail. It looked funny sitting out in the pond! Water covered that brown area and parts of the trail until a few days before we left to head farther east:

An even bigger surprise, however, was what the water under the Spillway Bridge looked like after Pilant Slough was drained. Here's a "before" shot from the long wooden bridge:

To the left is Pilant Slough. Less than a quarter mile ahead is the observation tower and 40-Acre Lake. To the right is Pilant Lake and the huge marsh area I showed in a previous picture. Some of that area drained but not as much as the swamp to the left.

Here's what this spot looked like on the fourth drainage day:


Bridge across the Pilant Spillway

The other side looked similar.

Note the six-foot alligator on the concrete (lower left side of photo above). I wonder where his buddy is? Every time I went across the bridge there were two of them near that very spot and occasionally a third one at the other end of the bridge.

I love the wide variety of trees, grasses, colorful red and green algae and aquatic plants that float on the surface of the lakes, sloughs, and marshes, and other things that grow in these wetlands. Here are some more examples:


Elm Lake, near a fishing pier


A duck floats through some reddish aquatic plants floating on the surface of Pilant Slough.


Our first alligator sighting! This big fella sunning himself next to the water near the Nature Center
was partly covered by the greenish-reddish plants floating on the surface of the water.

There is one other major ecosystem represented within Brazos Bend State Park:

3. THE TALL GRASS COASTAL PRAIRIES

The prairie "uplands" in the park were formed long ago when water covered much of what is now southern Texas. When the water receded the last time, huge grasslands grew all over this area of Texas and the Plains.

The grass supported millions of buffalo until the vast herds were mostly decimated. More recently, cattle grazed on the prairie land in what is now Brazos Bend State Park.

Because so much natural prairie land has disappeared with the development of farms, ranches, industry, and urban areas in Texas, the state has set aside some protected areas such as those at Brazos Bend. Park staff work to conserve and restore what is left of this vast ecosystem so visitors can enjoy at least some small communities of tall grass prairie.

The largest area of prairie that is open to visitors is near the park entrance. There is a short, flat trail across from the parking area for 40-Acre Lake that leads to a covered observation deck under a sprawling shade tree:

Nearby is a boardwalk leading to a wet area.

Wet area??


The Little Pond on the Prairie

That surprised me. I figured the prairie would be dry, even in March. Nope. Coastal prairies typically have lots of swales and depressions that become ponds during periods of heavy rainfall. I imagine this wet spot is dry in the summer.

I'd also guess the prairie is prettier in the summer when the grasses are fully developed and more colorful.  Or maybe not. At the end of winter it was definitely "quiet and subtle," as the interpretive guide diplomatically describes it. I probably would have enjoyed my prairie walk more if I'd taken the time to sit on the bench at the observation deck and watch for wildlife. I did see several deer run away as I walked in on the approach trail. They might have returned if I'd been sitting still for a while.

Next entry: some of the beautiful flowers blooming in the park in March

Happy trails,

Sue
"Runtrails & Company" - Sue Norwood, Jim O'Neil, and Cody the Ultra Lab

Previous       Next

2010 Sue Norwood and Jim O'Neil

-