Flood Damage - Plants

My greatest concern following a major flood event is the recovery of the streamside plant communities.  The plants must recover in order for the animals to recover.  Billions of small organisms were swept away with the leaf litter and topsoil.  Those that were left behind have lost the environment they need to survive.  Roots that once gathered nutrients from the decomposing leaves are left exposed to dry out and die.  It could be tough growing for some of the plants this spring.  The bare soil will dry out much more quickly and will heat rapidly when exposed to the sun.  Conditions will improve some when plants grow enough to shade the ground.  Soil creation can begin anew next autumn when falling leaves fill in the space between plants.

While some places lost their topsoil, others gained soil material.  Plants must now push their way up through a thick layer of sediment.

Both situations involve this stuff.  At one point these crumbs were all neatly stacked and arranged to form a cohesive block of soil.  In that condition they provided the structure needed for a healthy soil ecosystem.  Now they’re like shards of glass from a broken drinking glass; Recognizable pieces of what they once were, but no longer functional as a whole.  It will take a long time for these crumbs to be broken down and reformed into healthy soil.

In some cases, leaf litter was also redistributed.  Shallow water flows pushed leaves together to form tightly packed drifts several inches deep.  I moved some leaves aside to show the thickness of this pile and found a plant buried beneath.  Leaves packed at this density can form an effective mulch that blocks the upward movement of growing plants.

These Downy Rattlesnake Plantains were perched at the top of the bank at the high water line.  One still holds the stalk and seed capsules from last year’s flower.

Rhizomes that were just beginning to reach out into the surrounding soil, now have nowhere to go.

Plants farther from the stream were threatened by sheets of water flowing from the hillside.

Some areas closer to the channel hardly seem capable of supporting plants.  Had a logjam not developed directly upstream, there might not have been anything left here.

Just a few feet downstream of the logjam is the site of a single Large Flowered Trillium that has been growing here for about ten years.  It has bloomed several times during that period and flood water has flattened it about an equal number of times.  Hopefully it will be poking its way through in a few weeks.  I sometimes wonder if I should relocate plants growing in such precarious positions, but I figure there must be a reason for the plant to be growing on this site, instead of the many places I believe to be better suited. 

This Swamp Milkweed grows in the center of the creek channel where it’s anchored by one stout root in a crack between the rocks.  Most of its roots are exposed on the creek bed.  I figured it wouldn’t last long at all in this location.  Despite my opinion, the plant has flourished and flowered for the past several years.  It’s occasionally battered by flood water, but it bounces right back up and produces a beautiful floral display.  I’m hoping the rest of the plants along the creek follow its example.

Flood Damage - Floodplain

Probably the most visible effects of the flood are in the floodplain where water doesn’t normally flow.  A flash flood through the steeply graded corridors of the upper watershed can strip away everything in its path.  The resulting bare ground is impossible not to notice.

The stream corridor is primarily wooded, so the ground cover is composed of scattered plants and a layer of decomposing leaf litter.  This is not the type of material that can withstand the force of speeding flood water.  Somewhere downstream, a quiet backwater has received a deposit of rich organic material that recently covered the floodplains of Blue Jay Barrens.

Floodplains don’t necessarily flood each year.  The areas near the bank of this meandering creek receive flood water on a regular basis, but the majority of the area hadn’t been underwater for decades.  This flood ignored the channel location and filled the valley.  For a few minutes, this quiet creek did its best to imitate a river.

It’s easy to find the bounds of the flood water.  Until a few days ago, the creek bank resembled the leaf covered hill in the background.  Now the only floodplain leaves that remain are those wrapped around the small trees and shrubs.  During the next couple of months I’ll find out what spring wildflowers remain to add stability and cover to the bare ground.

Flooding is a natural event and its occurrence is beyond my control.  I can return the damaged bridges to their previous state by collecting and reassembling the various parts, but there’s nothing I can do to fix the barren floodplains.  All I can do is watch and learn as natural processes work to restore the floodplain soils.

Areas that only experience a few inches of moving water should green up nicely and quickly hide the evidence of their ordeal.

Other areas will show their scars for some time to come.  It’ll be years before I can walk along the creek without seeing evidence of the record Flood of 2012.  Even so, the floodplains will green up through the summer and after the autumn leaves fall, much of the disturbance will be masked.  Dealing with uncontrollable events is probably the most frustrating part of land management.  I know there’s nothing I could have done to stop the flood, but that doesn’t keep me from being aggravated by the results.

January Rain

This could pass as a typical January photo of Blue Jay Barrens if that was snow obscuring the view instead of rain.  Thunderstorms and 60 degree temperatures are not the norm for this area in the middle of January.  A quick moving storm front produced about an inch and a half of rain, most of which fell within an hour.  That certainly erased all traces of the snow storm from a few days ago.

Here is why I mow wetter areas first.  Once the spring rains begin, the ground is just too soft to mow without causing damage.  In normal years, the spring rains tend to arrive in months like March or April that are more traditionally identified with spring.

The upland water was moving away fast, so I splashed my way down to the creek to see what flooding was occurring.  This certainly isn’t the gentle flow I was admiring a few days ago.

If obstacles won’t move, the water goes around.  This curve will be a little bit wider by the time the water subsides.

The walking trail crosses the creek here because it’s usually just one long step to get across the water.  This definitely isn’t a good time to be crossing.

This bridge is the least susceptible to being moved by flood water.  There’s still a bit of clearance underneath, but the water appears to be striving to reach up as it passes beneath the bridge supports.  From here it looks like there are two creeks converging above the bridge.

The actual creek channel is in the background of the photo.  The curved section can’t handle the water fast enough and the excess has left the channel to travel overland.

The next bridge upstream is in a more precarious position.  It won’t take too much more water to change the structure from a bridge to a raft.  A large portion of the watershed for this creek is located upstream of Blue Jay Barrens.  Differing land uses allow more soil erosion to cloud the water with sediment.  Even so, this water is cleaner than the average stream of comparable size and the almost sediment free water from the Blue Jay Barrens tributaries improves the quality even more.

The bare soil areas that partially define the barrens look like they would be easily eroded, but the runoff water they produce is clear.  A healthy biotic crust of algae, lichens and mosses combines with a well defined soil structure and a pebbly surface to create an erosion resistant landscape.

The result is clean water leaving the barrens.  But, the integrity of the barrens soils is easily disrupted through disturbance.  This is why I have issues with the deer and turkey that trample and scratch the soil surface.  Damage caused by these animals can easily result in an active erosion situation that could be difficult to correct.  Management is just a matter of watching and reacting properly to changes.

Brush Pile

When your management activities include actions such as brush and tree removal, there develops a need to dispose of the accumulated woody material. I’ve chosen to pile cut trees and let the material decompose on site. The piles are located in places devoid of rare plants and provide a collateral benefit as wildlife cover. In some cases I’ve tried to gain an additional benefit from the construction of the pile.

Prior to the placement of this brush pile, there was a deep actively eroding gully on the site. In certain situations, cut cedars can be used to successfully stop gully erosion. The trick is to pack the cedars so tightly together that they form a fibrous plug through which runoff water must flow. The packed cedars slow and diffuse the flow of water while filtering out organic debris. Small cedars of seven foot height or less work best, because they have a high proportion of leaves and small stems and are easily compressed. Larger cedars should also be layered into the mix to help stabilize the pack. Once that mixture reaches above the gully walls, you can build the rest of the pile any way you wish.

Properly placed cedars will cause a pool of water to form upstream of the brush pile. Vegetative debris is left behind in the pool area and begins the accumulation of organic matter in the bare area once washed clean by the running water. The improved conditions make it possible for vegetation to grow and further protect the site from erosion.

Over time, small gullies that existed above the brush pile become filled and the area takes on the shape of a broad, flat bottomed valley. This gully erosion control technique only works on gullies with small watershed areas. The cedars would never stay in place in gullies that received a large amount of runoff water.

This area is now supporting a population of Shrubby St. Johnswort, one of my favorite plants. The brush pile was put in place in February 2001, so it has taken 11 growing seasons to reach this point.

The area below the brush pile is also supporting a thick vegetative cover. This is because the velocity of the runoff water has been greatly reduced by its travel through the pile. I’m now wondering what’s going on inside the pile and what will happen as the pile decomposes further. I’ll give it another 11 years and then see how things have progressed.

Erosion Self Healing

There are several other sites that shared a similar erosion problem as that of the tire dump. These areas are healing in a more natural fashion. This process takes a while and the landscape will retain the irregular features of the erosion sites. More conventional methods of vegetating eroded areas would not fit in with my goal to achieve a population of native plants whose origins are all from this property.

The point of active erosion still exists, but its progression across the landscape has been halted and no eroded soil leaves the site. Most of the vegetation in the foreground has established itself in the past 25 years.

The eroded face is transitioning from a vertical wall to a stable slope. Soil that crumbles from the top, is caught at the bottom. Roots from the grass cover atop the cut help hold the developing slope in place.

The once bare area below the cut now supports a healthy vegetative cover. It’s been fun to watch these areas fill with common plants and more recently support some of the rare species at Blue Jay Barrens.

There are several acres of this type of situation at Blue Jay Barrens. On my first visit to this field, I was shocked by the amount of bare soil. This was at a time before I had learned anything about barrens, prairies or their associated rare plants. Fortunately, purchase of this property put us in a situation where mortgage payments and other expenses were using up our money as fast as we earned it, so I couldn’t afford to do any of the traditional erosion control methods recommended at the time. A winning Super Lotto ticket could have put an end to Blue Jay Barrens before it ever began. However, a winning ticket now shouldn’t cause any problems.

Some areas are just too shallow to bedrock to support any lush growth. Many native annuals take advantage of the reduced competition on these rocky sites.

There are always setbacks. A few years ago, cattle from a neighboring farm took a self-guided walking tour of Blue Jay Barrens and chose to congregate here and trample the vegetation into oblivion. They gave their attention to several places, but this spot is having the most difficult recovery. I don’t know why they did this. Maybe they were just out playing Bison and decided to create a couple of buffalo wallows.

Deer also have ways of disrupting the healing process. They have made a trail down the bank that now carries a concentrated flow of water from the field above. I could easily block their trail, but they would just move over and create a new trail on a different bank.

Maybe there really is something miraculous involved with the recovery of this field. If the grass can grow out of solid rock, it can grow anywhere.

Tire Erosion Control

It’s not unusual for rural properties to contain an area or two that were used as dump sites for trash and other discarded items. Blue Jay Barrens has a few dumps, but of course there hasn’t been anything added to them since I bought the property. I believe that somewhere in their minds these people knew that dumping trash was not the right thing to do. To ease their guilt, they all subscribed to the popular rural myth that dumping junk onto an actively eroding area would stop the erosion and heal the earth. I’ve never had any of these people give me a good explanation of how a pile of trash can promote healing.

When I began managing Blue Jay Barrens, this was a site of active erosion. Water flowing from the hilltop to the right dropped over a low embankment and scoured away the soil as it fell. A double row of tires and other miscellaneous junk concentrated the water flow as it moved downhill and caused tiny gullies to form between the tires. Long deltas of mud formed where the water emerged from the junk. When I began clearing the surrounding prairies eleven years ago, I covered the whole junk pile with small cedars. I didn’t have time to remove all of the junk, so I thought I would just do what I could to stop the erosion and stabilize the area.

The erosion has been stopped and the cedars have decomposed to the point where the tires are once again visible. It’s obvious that the tires were placed in a particular arrangement and not just thrown from a wagon or truck. The tires were set in neat rows and in areas where the eroded area were deepest, the tires were stacked. I suppose the tires were originally placed up against the edge of the embankment, but then the embankment eroded further and left the tires behind.

I have to commend the creators of this tire wall for getting every mile they could out of these tires. Had they been more safety conscious, I would probably have twice as many discarded tires, all having a little bit of tread left.

I packed the gap between tires and embankment with small cedars and then piled cedars about four feet deep over the tires. As the cedar decomposed, leaves accumulated in the resulting void and provided a filter for the water. Now instead of cascading like a waterfall, the water slowly filters through the leaves.

Vegetation has claimed the area downstream of the pile. There is currently no active erosion on this site. If this was a tall grass site, you’d never see the trash. Now that the cedar pile has rotted down to almost nothing, even the short grass does a good job of hiding the dump. A healthy White Flowering Dogwood is helping to camouflage the site.

Some of the material they dumped here has actually provided good habitat for some of the prairie dwellers. I’ve seen skinks and fence lizards sunning on these discarded fence posts. Mice and voles and a variety of insects have found shelter in this pile of timbers.

Sitting at the base of one post was this pile of strange curls. They might be tiny parchments or curls of old tape or shavings from some type of craft project. Actually, they’re curled belly scales from a shed snake skin. I can imagine a Black Rat Snake living here. That probably makes this a less desirable place for the small rodents to hang out.