Tom's Blog

Thursday, September 5, 2019

Annual Labor Day field trip at Pleasant Valley Conservancy

Kathie and I have been running the Labor Day trip at PVC annually since September 2002 (17 years). If the weather is good, attendance is fairly high, generally 25-40 participants.

Update! Just added Arlene Koziol's You Tube video of the field trip. Click on link

Last year the weather was unbelievably foul and only 2 people showed up, the 2nd about 45 minutes late. (Yes, the weather in southern Wisconsin can really be that bad!)

As the years have gone by, my participation in this trip has been a challenge. Since I turned 85, Kathie has done the walking and I have used our Kawasacki Mule to cover the course. I  stay in front and stop at key sites to lead the discussion.

Group for the 2019 Labor Day field trip. Photo by Arlene Koziol

Wednesday, July 31, 2019

Surprising resilience of a black walnut tree

As I discussed in a 2017 post, black walnut (Juglans niger) is one of the bad guys in oak savanna restoration.

As that post also discussed, walnut trees are fairly difficult to eradicate permanently. Recently, Kathie and I have found a good example of this (see photo below).

This greatly deformed tree is close to what we call the “Circle Prairie”, a small mostly remnant prairie that I have    discussed in detail in the post linked here. 

There was a large walnut tree formerly in the middle of the Circle Prairie. It was removed in the winter of 2015-2016. To get rid of the substantial amount of wood (small branches, limbs, and trunk), the tree was cut up and piled adjacent to another walnut tree, the one shown in the photo here. There was a lot of wood, and a large pile was built. When the pile was finished, just before starting the fire, one of the crew climbed to the top of the burn pile and lopped off the main trunk of the tree being used as an anchor. (The intention was to also throw the wood of the anchor tree on the burn pile.)

The roaring fire of this burn pile was tended and consolidated in our usual manner. The intention was when we were finished to end up with only ashes. Unfortunately, the crew ran out of time and the anchor tree, topped and coal black, remained as a ghost.

Fast forward to July 25, 2019. Kathie was doing some weeding in the Circle Prairie and noticed the strange tree shown in the photo. The tree is growing vigorously with several large leafy branches. The trunk is pitch black, attesting that it was this tree that participated in the burn pile of 2 ½ years ago.

Explanation? Probably because of the cold weather when the burning took place, some dormant buds near the top of the tree survived the fire and resprouted. But how did the cambium survive that very hot fire, attested to by its black trunk? Presumably the temperature did not get hot enough on the side of the trunk away from the fire.

We have plans to remove this outlandish tree sometime next winter.

Wednesday, June 26, 2019

Exploring the wetland at Pleasant Valley Conservancy

The wetland at Pleasant Valley Conservancy is small but diverse, and a lot of it can be reached with (relatively) dry feet. As part of some management activities, Craig Annen of Integrated Restorations has put together a map showing the wetland communities. I have added trails (in red) in the version shown here.

The most widely used wetland trail at PVC is the one that is between the two prairie buffers and the sedge meadow. This trail is almost always dry, and Kathie's mowing keeps it open. (The butterfly people love it!) It also connects to the boardwalk which also provides dry-foot access for a short distance through standing water. The rest of the trail on the other side of the sedge meadow is more of a challenge,  especially in 2019 because of the heavy rains.

The detailed description of the wetland flora can be found at this link to the PVC website. The point of the blog post is to publish this new summary map.

Wednesday, May 8, 2019

Best year ever for spring burns at Pleasant Valley Conservancy

We have been doing burns at PVC for 22 years and we burned more acreage this year than ever.

We always have ambitious burn plans but conditions are not always cooperative. This  year things just worked out, and we burned 131 acres of the 140 acre Conservancy. These were all dormant-season burns. Because of the long period of degradation before restoration began, we are always fighting the legacy of invasive woody plants, and the best way to deal with them in our Conservancy is with fire.

The table and ArcMap summarize the burns.

Date of burn
Habitat type(s) burned
Crew size
March 21
South-facing slope; prairie and savanna
March 22
Restored prairies
March 26
Mainly savanna; Pocket Prairie; read narrative
March 27
Oak woodland & prairie
April 9
April 19
North-facing oak woods

Total acreage

Not all the wetland acres burned, since there is standing water in a number of areas. Also, the coverage in the North Woods was not 100% either, but fire passed across >90% of the area.

The March 22 and 27 burns were fairly routine, involving mostly planted prairies. The present post focuses on the March 26 burn, which was predominantly oak savannas. Although a large and complicated burn, we had a crew with lots of savanna burn experience and everything went off      quickly.

It is important to do lots of prep work for a savanna burn, especially clearing around standing dead snags to eliminate lots of time-consuming mop-up work. On a burn of this size, that takes most of a day. The work must be done ahead of the burn, but not too many days ahead.

We have two types of savannas, and both were burned the same day.
  • Ridge-top savanna, predominantly bur oak with a significant hickory component. This is the top area, on the dolomite, and mostly on both sides of the gravel service road. It includes Unit 19 and  Units 11A, B, and C.
  • Basin savanna, predominantly white oak with some hickory. This is on the sandstone, and surrounds the Pocket Prairie. It includes Unit 11D, 12A and B, Unit 18 and Units 20 A-C.

And then there is the Pocket Prairie. Although not savanna, the Pocket Prairie is always burned at the same time the Basin Savanna is burned.

Because of the steep slope and the wind, the anchor-point for the burn was where the Side Road meets the main Service Road. The long, narrow units north of the service road (Unit 19 B through E) were burned separately (crew of 4) at the same time as the big main burn (crew of 8). As soon as the Unit 19 burn was finished, that crew joined the other and did more interior lighting.

Ridge-top units 8 and 10 had already been burned during the March 21 burn and provided a solid black line uphill and downwind. Also, the Unit 7/Unit 18 boundary was secure because Unit 7 had been burned on March 21.

Running the burn Drip torches moved east and south in Unit 11A from the anchor point along the two roads. As soon as the starting area was solidly black, other drip torches moved into the burn units for interior lighting. This is essential because a savanna fire almost never backburns through a whole unit without “help”. The Unit 19 crew joined the main crew for extensive interior lighting of the Basin Savanna.

Two-way radios Each crew member had a two-way radio, and it was vital that the burn boss and line bosses monitor progress. Most crew were out of sight of each other. It is especially important to monitor for potential head fires due to wind shifts or changes in topography. As the map shows, there are several ATV trails that follow the contours of the units, which interior lighters can use as guidelines.

Mop-up There was very little mop-up. After the burn, I drove one of the UTVs through the upper trail, which gave a good view of both the ridge-top and basin savannas. There were no standing smokers, and few smokers on the ground. The latter is not surprising, since we have been burning these savannas annually for many years.

Pocket Prairie burn After the basin savanna is completely black, the Pocket Prairie is usually burned as a head fire. Given reasonable wind and R.H., it generally takes about 10-15 minutes to burn. By this time, all of the crew are out of the savanna units (which are totally black) and are watching from the road.

We started lighting at 9:57 AM and finished the Pocket Prairie at 11:39 AM. So the whole burn took 1 hour and 42 minutes (102 minutes)

Amanda ran the burn. Here she is doing crew assignments

Initial lighting

The fire has reached the corner of Unit 12B. It is now off the Ridge

Interior lighting just before the fire moves into the Basin Savanna

Waiting for the final interior lighters to finish and leave the burn

Watching the Pocket Prairie burn

Wednesday, May 1, 2019

Volume II of the history of restoration at Pleasant Valley Conservancy

We've had quite a few favorable comments about the history of Pleasant Valley Conservancy that Kathie and I have been preparing. Volume I has been available for several months. If you missed it, here's a link to the previous blog post which has a download link.

Volume II is now available without charge for download at this link. 

Volume II has more text than Volume I but the file size is smaller  (22.3 MB) because I discovered that photo resolution can be reduced more (than Volume I) without hurting the image too much. (This assumes you are reading the book on a screen. Don't try to print from this PDF!)

The second volume of the history of PVC restoration is organized chronologically from 2001 through 2008. The year 2008 seemed a good year to end, as this was the year we celebrated becoming a dedicated State Natural Area.

Some of the features of the book:

  • Hyperlinked table of contents including all #1 heads
  • #1 heads bookmarked
  • Text completely searchable and accessible by voice readers
  • Downloadable to an iPad or other reader and conversion to an iBook
  • (These features also available in Volume I.)
Some of the content items:
  • Cost analysis of restoration work
  • Creating a budget for a contractor
  • Bluff (South Slope) prairie burns: procedures and problems
  • Oak savanna burns: procedures and problems
  • See how our burns get better as the years go by!
  • Major (140 acres) Fish & Wildlife Service wetland burn at PVC
  • First case of chronic wasting disease
  • First breeding bird survey
  • Preparation of detailed species list using Excel
  • Floristic Quality Index of  PVC
  • First PVC website
  • Summer interns
  • Winter interns
  • Field trips
    • Natural Areas Association
    • North American Prairie Conference
    • Landowner group
    • Labor Day trip
    • McHenry County Conservation District
    • University classes
  • East Basin restoration (heavy brush clearing project)
  • Dedication of PVC as a State Natural Area
    • Ceremony, field trips, and party: June 7, 2008
  • Seeds and planting 
  • Lots more!

Saturday, March 23, 2019

Protecting trees in a bur oak savanna burn

 The south-facing slope at Pleasant Valley Conservancy is a good example of a bluffprairie. Such bluff prairies are common in the Driftless Area. However, although most of these sites are called “prairie”, most of them are actually bur oak savannas.

In a well-restored site, fire is the principal management tool, but there are significant difficulties when trees are present. Because of the steep topography (slopes up to 75 degrees), even in the absence of wind, head-fire flame heights can be 15-20 feet (occasionally even higher).

The bur oak trunk is very fire resistant, but its branches are less so and with high flame heights can be easily damaged. Thus, despite the recognized fire tolerance of the bur oak, even large trees can become seriously harmed.

When we first started burning the South Slope at PVC, the fuel was very spotty and fire did not carry well, so we mostly burned as a head-fire. Annual burns, accompanied by brush control and overseeding, gradually turned the South Slope into a tallgrass savanna. It was about burn year 5 that fire with high flame heights carried up into the bur oaks. Lots of branches caught on fire, and mop-up was a major problem.

Since then we have tried to back burn the South Slope, especially its bur oak component. A few years later we added tree-centered spotfiring as an additional protection, especially for the smaller trees.

The photos below show how we did the South Slope burn this year.

Starting the burn at the top of the South Slope. Depending on fire behavior, a second drip torch may be used to speed up the process.

Far end of the ridge. Backburning around ancient bur oaks

Above: Tree-centered spot firing small bur oaks. The blackened area protects the saplings from a  possible head fire.

Above. Later stage. The blackened areas have grown larger.

Above. Later stage. The black areas have coalesced and the continuous fire line is backing through the tallgrass prairie.

Once the bur oaks are completely in the black, the burn can be speeded  up by lighting a head-fire from the bottom.

The bur oaks are now "safe" in the black. The lower area is darker because it was burned as a head-fire.
The burn was done on March 21, 2019. Amanda was the burn boss.

Wednesday, February 20, 2019

Keeping track of the prairie & savanna acres restored

Once we got seriously into prairie/savanna restoration, I kept track of the work by measuring the acres restored.

It was easy to do with a Garmin. I just walked around the periphery of the area cleared each year with the GPS area routine on, and then pushed "calculate". Having these numbers was really important, because it helped in setting budgets and goals.

The graph here summarizes eight years and 70 acres of work and the air photo gives a concrete look at what has been accomplished.

To read a history of the early years of restoration, download this link (44 MB)

The air photos make the process seem more real!