Tom's Blog

Sunday, November 13, 2016

Biennial oak woodland burn at Pleasant Valley Conservancy

After a quite rainy autumn, the weather turned very favorable and we had a successful burn of our oak woodland on Thursday November 10, 2016. This has been one of the best years for doing fall burns.

We burn our North Woods every other year, usually in the fall of the year. The last time we burned it was in 2014, and details of that burn can be found on this post.

A successful burn depends on proper fuel, proper weather, and a good crew. We had all these last Thursday.

The first time we burned this oak woodland was October 1999, and we have been burning it on a biennial schedule since 2008. The predominant species is red oak, with substantial white oak and a large patch of Hill's oak in one area. Also, scattered bur oak, especially on the upper ridge.

The topography is rugged, with about 200 foot vertical drop from the upper ridge to the County highway. We have a good fire break at the top of the ridge, and always start the burn there, moving in two directions and then down the ridge to the highway. This year we extended the burn a little on the west and (especially) on the east, where there is a fine basin with many large white oaks. Parts of this latter basin had probably not been burned in 80 years, if ever.

Most of the fuel was oak leaves, which had come down over the past two weeks.

Start of the burn of the white oak woodland at the east end of the site.
The fire backburned almost all of the way down the hill.
Only a small amount of interior lighting was needed here.

The weather was quite favorable. A dry air mass had come in, promising clear skies and warm air. When lighting started at 11:30 AM the RH was 43 and the temperature about 60 F, with light wind. These conditions held all afternoon.

After a good black line had been made over the whole periphery, a lot of interior lighting was done, to speed up the burn. When we went home at dark there were still some fire lines moving, and several smokers, but these were well inside the unit and were allowed to burn. (This is our standard practice for oak woodland and oak savanna burns.)

The next day Kathie and I did a survey of the burn coverage. Most of the areas that we expected to burn were black. In all, a succesful burn.

Wednesday, November 9, 2016

Great fall burn at Black Earth Rettenmund Prairie

Although we often have trouble getting satisfactory prairie burns done in the fall of the year, this year has been an exception. The prairie grasses have all cured early and the weather has been cooperating.

On Monday Dane County Parks burned the prairie remnants at Walking Iron.

Today Amanda and the folks at Integrated Restorations LLC did the burn at Black Earth Rettenmund Prairie that we generally only do in early spring. What a joy to have that burn already out of the way!

We have three burn units at BE Prairie, and burn two of the three each year. The schedule is arranged so that each unit is burned in two consecutive years, followed by an unburned year. This was the year to burn the South Unit and the Saddle. See the burn history and projected burn schedule through 2023 at the end of this post.





Fire line moving across the Saddle.
The fuel here is predominantly warm-season grasses (Indian grass,
and big and little bluestem), but lots of the forbs burned well also.

Sean doing some interior lighting in a patch of cool-season grasses.
One reason we wanted to burn in the fall is so that we could spray this patch of cool-season grass early next spring.
This patch developed during the major drought we had in the summer of 2012.


After the burn. Burn coverage was greater than 90%.
The lane here separates the prairie from the neighbor's alfalfa field.
This lane is our fire break and means of transportation to the South Unit.

One difference between this fall burn and our usual spring burns is smoke. Although the warm-season grasses are fully cured, there are still lots of small green patches, either uncured cool-season grasses, or fall regrowth of spring perennials such as wood betony and prairie violet. These green plants always burn with lots of smoke. Fortunately, the prairie is far enough away from the highway so we did not have to worry about traffic control.





Great fall burn at Black Earth Rettenmund Prairie

Although we often have trouble getting satisfactory prairie burns done in the fall of the year, this year has been an exception. The prairie grasses have all cured early and the weather has been cooperating.

On Monday Dane County Parks burned the prairie remnants at Walking Iron.

Today Amanda and the folks at Integrated Restorations LLC did the burn at Black Earth Rettenmund Prairie that we generally only do in early spring. What a joy to have that burn already out of the way!

We have three burn units at BE Prairie, and burn two of the three each year. The schedule is arranged so that each unit is burned in two consecutive years, followed by an unburned year. This was the year to burn the South Unit and the Saddle. See the burn history and projected burn schedule through 2023 at the end of this post.





Fire line moving across the Saddle.
The fuel here is predominantly warm-season grasses (Indian grass,
and big and little bluestem), but lots of the forbs burned well also.

Sean doing some interior lighting in a patch of cool-season grasses.
One reason we wanted to burn in the fall is so that we could spray this patch of cool-season grass early next spring.
This patch developed during the major drought we had in the summer of 2012.


After the burn. Burn coverage was greater than 90%.
The lane here separates the prairie from the neighbor's alfalfa field.
This lane is our fire break and means of transportation to the South Unit.

One difference between this fall burn and our usual spring burns is smoke. Although the warm-season grasses are fully cured, there are still lots of small green patches, either uncured cool-season grasses, or fall regrowth of spring perennials such as wood betony and prairie violet. These green plants always burn with lots of smoke. Fortunately, the prairie is far enough away from the highway so we did not have to worry about traffic control.





Tuesday, November 8, 2016

Walking Iron Prairie fall burn


The fall weather this year has provided good conditions for small prairie burns. See my post for a general discussion of fall prairie burns.

Walking Iron Prairie, part of the Dane County Park System, is an excellent small prairie known for its outstanding displays of pasque flowers in the spring. Also noteworthy is Hill's thistle, prairie smoke, white prairie clover, and Carolina puccoon. At one time the Empire-Sauk chapter of the Prairie Enthusiasts had a web page on Walking Iron, but this got deleted during a modernization activity. Since I wrote this web page, I am taking the liberty of copying the key content at the end of this post.

However, this prairie thrives on being burned, and for the past ten years, due to a set of unusual circumstances, burns have mostly been nonexistent. This year a group of dedicated Dane County Parks volunteers led by Denny Connor, came together and, using the highly favorable fall weather, burned the key portions of the site.


Wetlining the fire line in preparation for lighting (Denny and Ron).
Lots of black oak grubs will be set back by the fire, thus keeping the prairie open.
A wide hiking trail goes through the middle of the prairie. The unit on the right has already been burned, and the unit on the left is now being burned. Note the large brush patch burning.



Enjoying Walking Iron County Park




Walking Iron County Park

Ownership and History
Walking Iron County Park is owned by Dane County. Walking Iron County Park has 288 acres offering miles of hiking and equestrian trails winding through restored prairies and wooded areas. The prairies represent only a small part of this acreage. The Village of Mazomanie was established in the 1850s as an important railroad stop and the term “Walking Iron” derives from a Ho-Chunk word for railroad: “the iron that walks”.

Access
There are three entrances, one inside the Village of Mazomanie at 636 Hudson Road, an entrance to horse trails at 645 Segebrecht Road; and the principal entrance at 6064 Beckman Road in the Town of Mazomanie. The entrance to the prairies is the Beckman Road entrance, reached from Hudson Road just west of the village. From Hudson Road turn right onto Beckman Road soon after crossing the Black Earth Creek bridge. The Park entrance is about a mile to the north.

Description and significance
Although Walking Iron County Park is in the Driftless Area, it was profoundly influenced by the glacier. The melting of a large ice mass near Middleton caused formation of a major river, which laid down thick sand beaches extending far into Iowa County to the west. Most of the Park is located on sandy uplands that extend north toward present-day Wisconsin River.

The prairie here is a remnant of the vast original prairie that extended through the sandy Wisconsin River bottoms west to Spring Green and beyond. Areas that were not prairie were oak savanna or bottomland forest. European settlers commented on the beautiful fields of colorful flowers here.
The highlight of Walking Iron Park is Pasque Flower Prairie, a prairie remnant reminiscent of prehistoric times. Prehistorically, the Native Americans used fire to maintain their hunting grounds. After settlement, it was kept open in part by natural wildfires. In present times, prescribed fire is managed by Dane County Parks.


The best known plant of Pasque Flower Prairie is, of course, the pasque flower (Anemone patens) itself. This is one of the earliest blooming species in the prairie, often appearing very soon after the final snows have melted.

Other colorful plants of the spring flora are lupine, prairie smoke, and sand puccoon. Mid-summer flowers include white and purple prairie clover, yellow coneflower, bergamot, and rosin weed. In the late summer the prairie grasses wave in the breeze. Early fall brings goldenrods, asters, and gentians. There is always something blooming in Pasque Flower Prairie.

To the east and north of Pasque Flower Prairie is a nice oak savanna, which is being kept open by occasional prescribed burns. Among the oaks are prairie and savanna grasses and a characteristic flora of savanna forbs.

Volunteer work parties are occasionally held at Walking Iron Park, for the control of invasive brush and weeds. For information, send an email to:

Rhea Stangel-Maier
224-3601
stangel-maier@countyofdane.com





Wednesday, October 26, 2016

Prairie burns in the fall?

Why is it so hard to get a good prairie burn in the fall?

Update 11-1-2016 See bottom of this post
******************************************************************
It would be nice if prairies could be burned in the fall. Not many people are burning so it is easier to get a burn crew together. In our area, no DNR permit is needed, which simplifies scheduling. 

Unfortunately, fall prairie burns are difficult to accomplish effectively, primarily because the principal fuel, warm-season grass, is often not cured.

What is curing? Most tallgrass prairie species go through a life cycle that involves growth and seed production, after which the above-ground plant matter undergoes senescence followed by death. (In perennial grasses, the roots remain alive and carry the plant through to the next growing season.) During senescence the leaves start to lose their chlorophyll and brown patches or spots appear. At about 50% cured, whole sections of the leaves become brown and gradually the whole leaf becomes brown. At this point, the grass is 100% cured. From then on, the moisture content of the plant will no longer depend on the plant itself, but on past rainfall and relative humidity.

The curing process will vary with the year, and with the site. The progression of curing will be different in different prairies, and will be affected by rainfall and temperature. Even in a single prairie, curing can be patchy.


Most of the research on curing has been done in Australia, and involves completely different species and different habitats. But the general principals are the same. Here’s a link the the Australian work.

If the prairie is not burned annually, some of the fuel will be dry residues from previous seasons. This material is of course fully cured but will not carry a fire as well as fully cured prairie grass from the present growing season.

There is also a U.S. curing guide focusing on the Great Plains, provided by the U.S. National Weather Service. In addition to the data in tabular form (see below), there is also a photographic guide, which can be found at this link.


In our climate in the southern part of the Upper Midwest, curing is a rather slow process, and may often not be completed before the snow flies. This explains why fall prairie burns are often unsatisfactory.

However, not all is lost. We have actually had a quite successful prairie burn in early December in a year when snow was late in coming. The grass then was fully cured. We wanted to burn then so that we could get all the thatch out of the way so we could spray smooth brome as soon as it came up in the early spring.

A December burn just takes luck and an ability to move immediately when conditions are right. Periodic monitoring of the site is essential.

Also, I have seen years when prairie burns could easily be accomplished on the odd day in either January or February. Obviously these are not fall burns, but the grass then is fully cured.

Update 11-1-2016

This just in from the 11-1-2016 survey.
The warm season grasses at Pleasant Valley Conservancy are now fully cured. (See photos below) This is earlier than usual.

In fact, a good burn could have been done. Here was the situation:

In the morning the humidity was fairly high and there was dew on the grass everywhere. But by noon the humidity had dropped and the temperature was rising. By 3 PM the humidity was about 40% and the temperature was 72 F. A great time for a small prairie burn. Just a light wind.

This emphasizes one of the demands of doing controlled burns: the ability to jump when the conditions are right.

And you obviously can't wait until tomorrow, because tomorrow (now today) it is raining!

Fully cured  Indian grass in the Barn Prairie. Ignore the green, which is an adjacent mowed lawn.

Fully cured prairie grass, ready to burn.
By 3 PM the RH was 40% and the temperature was 70 F. Light wind out of the NE.


Friday, October 21, 2016

Hill's oaks and fall color at Pleasant Valley Conservancy

This has not been one of our better years for fall color. The last half of September was cold and rainy, and it has only been in middle of October that we really had any color, and it went fast.

I had a post in 2010 which gives some detail about Hill's oaks at PVC. Here are two pictures showing fall color. According to some sources, Hill's oak is sometimes planted in urban areas because of its nice fall color.





Both of these photos were taken around the edge of Toby's Prairie, which is the area with the most Hill's oaks.

This species is found primarily in sandy areas. Those specimens around Toby's are mostly still fairly small, but there is an area with larger Hill's in Unit 19B, as shown on the distribution photo below.






Monday, October 10, 2016

Mullein control: to dig or spray?

Mullein (Verbascum thapsus) is a common invader in the early stages of prairie or savanna restoration. It can't compete in well established native areas, but comes in quickly on bare ground, which is common in the early stages of a restoration. Since it is a biennial, it is important to prevent seed formation.

We used to dig the rosettes with a shovel (a Parsnip Predator is ideal). However, in the early stages of the East Basin restoration we had hundreds of mullein plants, making digging a formidable job. Since there wasn't much else green, we sprayed them all with glyphosate, since that has no residual soil activity.

Once mullein is under control, one still finds the occasional plant cropping up. Yesterday I found one at the edge of the rock outcrop at the East Overlook. Since I had my shovel with me, the first thought was to dig it up. However, it is virtually impossible to get all the roots when digging in a rocky place.

I also had my Garlon 4 spray bottle with me, and it was much easier just to spray the center of the rosette, which is enough to kill the whole plant.

I can't emphasize the usefulness of a spray bottle containing Garlon 4 at 15-20% in bark oil. I always carry one with me. I use it for basal barking any small shrub that may have been missed (buckthorn, honeysuckle, sumac, etc.). And it also works for herbaceous plants such as mullein, burdock, sweet clover, parsnip, bird's foot trefoil, etc.

With these herbaceous plants, with a high concentration-low volume herbicide mix, you don't need a complete foliar spray. Just the center of the rosette is enough to kill the plant.

Mullein plant growing out of the rocks. Digging is almost impossible here,
but a brief spritz in the center of the rosette will do the trick.