Tom's Blog

Friday, September 28, 2018

New England asters and Monarch butterflies

This is the time of year when the last brood of Monarch butterflies is stoking up for their long journey to Mexico. Asters and goldenrods are the principal nectar sources, but by now most of them have stopped flowering. Fortunately, New England aster is still flowering and this is what the Monarchs are using. Often considered a weed by purists, it has the good graces to hang on longer than anything else.

A few years ago at Pleasant Valley Conservancy a butterfly watcher about this time of year counted 43 Monarchs on a single NE aster plant.



Although both of the above photos are from restored savannas, you can find New England aster as a volunteer in old fields and roadsides as well. I've been watching one of my neighbor's fields since it was last cropped four years ago and have been fascinated at how quickly "weedy" prairie species from PVC have moved in.

Last year it was old field thistle that had moved in. See this link.

This year it is New England aster, as the photo below shows.

New England aster growing in an old field adjacent to PVC that is gradually being colonized. Two plants of old field thistle can be seen in the background. The seed source is our East Basin prairie which is about 100 feet away. This field has been fallow for only four years. The small white flowers are probably frost aster. The goldenrod is (predictably) Canadense.

Tuesday, September 25, 2018

The gentians: fringed and otherwise

This is the time of year for gentians. As poet Emily Dickinson so aptly put it, gentians come with the frosts, although with global warming since Dickinson’s time, it has not frosted yet. Cream gentian (Gentiana alba) comes a little earlier, but right about now we have the following:

·         Bottle gentian: Gentiana andrewsii; perennial; seeds flattened and winged
·         Stiff gentian: Gentianella quinquefolia; winter annual or biennial; seeds smooth and round
·         Prairie gentian: Gentiana puberulenta; perennial; seeds flattened and winged
·         Fringed gentian: Gentianopsis crinita; biennial; seeds oblong-angular, covered with papillae

The famous and even rarer Great Plains fringed gentian (Gentianopsis procera; Special Concern) is the species found at the Ridges Sanctuary and other locations along the Door County beaches.

According to Cochrane and Iltis, gentians are “beloved by botanists” and are “A large, cosmopolitan family, mostly in cool, moist, habitats. Our gentians are all essentially prairie or fen species that, becoming rarer year by year, should never be picked or transplanted except as a last resort in the face of impending destruction.”

Right now, at PVC we have in flower all four gentian species from the above bullets: stiff gentian (widespread); bottle gentian (well established in the Crane and Valley Prairies); prairie gentian (in the Ridge Prairie), and fringed gentian (the marsh/fen edge near the barn). Stiff gentian was native to PVC but the three others were planted from local genotype seed.

It is the fringed gentian that interests me here. Over the last 3-4 years we have been able to get this handsome species well established in the wet-mesic prairie near the barn. Ten years ago this wetland was a solid monoculture of Carex trichocarpa, but then I discovered that lousewort (Pedicularis lanceolata), a hemiparasite, could infect the sedge and keep it in check. We started throwing out lousewort seeds. Gradually, as the sedge disappeared,numerous other wetland species became established.

Some years ago, Kathie planted bottle and fringe gentian seeds in this area. (The seed came from another wet-mesic site in Dane County.)

 Since fringed gentian is a biennial, continued presence at a site depends on good seed production and subsequent germination and growth. The area we chose must be favorable because this year we have dozens of flowering patches.


Fringed gentian (by Emily Dickinson)
God made a little gentian;
It tried to be a rose
And failed, and all the summer laughed.
But just before the snows
There came a purple creature
That ravished all the hill;
And summer hid her forehead,
And mockery was still.
The frosts were her condition;
The Tyrian would not come
Until the North evoked it.
"Creator! shall I bloom?"



Notes: Roses bloom in summer but gentians bloom at the end of summer, just before or after the first frosts
Tyrian is a type of “purple”, Royal purple. The color would not appear until frost had arrived.

Poet William Cullen Bryant has a poem called “To the fringed gentian”(first stanza below)

Thou blossom bright with autumn dew,
And coloured with the heaven’s blue,
That openest when the quiet light
Succeeds the keen and frosty night.

The internet is full of fringed gentian lore. Indeed, there is a Gentian Research Network at Rutgers University.






Fringed gentian habitat at PVC. Visible from the lane next to the Valley Prairie.
This time of year, most of the other wet-mesic species are finished blooming.




Monday, September 24, 2018

2018 Survey for Bur Oak Blight at Pleasant Valley Conservancy Update 9-30-2018


Update Sept 30, 2018

The report below was written on Sept 23. Since then, lots more trees are showing symptoms of bur oak blight.

Many are large trees, including some icons.

I am hoping that the unusually humid weather this year is responsible, and that no long-term damage will befall our bur oaks.

We'll see what next year brings!

***************************************************************

I first reported bur oak blight in a small number of trees at PVC in 2017.

Infected leaves exhibit purple-brown lesions along the veins on the under side of the leaves. These lesions gradually expand and in many cases the leaf turns completely brown. Black fruiting structures of the causal agent, the fungus Tubakia iowensis, appear and are diagnostic for the disease.

Although not fatal, we felt it desirable to continue monitoring this affliction. The trees that were infected last year leafed out normally, but symptoms started to appear in late August. Yesterday, about a month later, the symptoms were more extensive, although some leaves were still not infected.

We also noticed blight on some trees that had apparently been fine last summer, including the classic open-grown bur in Unit 10 that I have often used in photographs. Also, our oldest bur oak, the patriarch of the savanna, does not seem to be infected as much this year as last.

But most of our bur oaks, both small and large, remain healthy.

Bur oak blight infection is apparently associated with humid weather cycles and the past two years have been unusually rainy. Since long-term weather patterns generally alternate between wet and dry years, we can hope for some drier years (although nothing like the 2012 drought!).

Since the symptoms do not appear until late summer/early fall, the leaves on infected trees have most of the growing season to function normally, photosynthesizing and translocating nutrients to the roots. Even now, most leaves are only partially affected.

Bur oaks regularly lose there leaves earlier in the fall (usually mid October) than do most other oak species, so it won’t be long before the leaves will be dropping. Thus, there is a narrow window, mostly the month of September, when bur oaks can be monitored for blight.

The scientific paper describing this disease in detail can be downloaded from this link.



Thursday, August 2, 2018

Establishment of compass plant (Silphium laciniatum) in prairie and savanna habitats


Compass plant (Silphium laciniatum), an icon of the tall grass prairie, is one of the first prairie species to disappear upon grazing (see Curtis quote at the end of this post). At Pleasant Valley Conservancy it was completely absent from the unrestored prairie remnants, even though many other prairie species (including such conservative species as Amorpha canescens; Sporobolus heterolepis; and Ceanothus americanus) were still present.

When restoration began, compass plant was high on our priority list for reintroduction and it has been in all of our seed mixes for planting on all prairie or open savanana sites after they had been cleared and burned. However, it is slow to develop, and the first year all one usually sees is a single leaf. It continues to grow only vegetatively for the first few years, just making a large tap root. Although in favorable garden-like settings it can flower the second or third year after planting from seed, in most prairie restorations it takes at least five or six years to flower.

The first plantings at PVC were on November 1998 at the former ag field (future Toby’s Prairie) and at the recently cleared Overlook area (Unit 5A) on the South Slope. The Overlook area was planted again in April 1999 after burning. The first flowering plant at Toby’s Prairie was in 2004, six years later, but flowers were not seen at the Overlook until 2007 (nine years later).

The Overlook has the appearance of a severe habitat, highly exposed, with a rocky soil and intense solar radiation. Despite this, flowering compass plants have continued to be present at the Overlook since it was first restored. In 2018 there were three tall flowering plants.

As the table shows, we have been successful in getting compass plants established from seed at a wide variety of sites. It is now widespread at Pleasant Valley Conservancy, in various kinds of prairies as well as open savannas.

Compass plants from seed to first flowering
Year planted
First Year flowered
Location
Habitat
Years to flowering
2002
2006
Barn
Wet mesic prairie
4
2002
2008
Cabin
Dry mesic prairie
6
2005
2007
Crane
Wet mesic prairie
2
2003
2014
Unit 11A
Open savanna
11
1999
2004
Pocket
Mesic prairie
5
2005
2010
Ridge
Dry mesic prairie
5
1998
2004
Toby’s
Dry/Dry mesic prairie
6
1998
2016
Unit 5A
Dry prairie
9
2003
2008
Unit 11A
Open savanna
5
2004
2009
Unit 11D
Open savanna
5
2002
2006
Unit 12A
Open savanna
4
1999
2005
Unit 18
Dry mesic prairie
6
2002
2012
Unit 19B
Open savanna
10
2002
2008
Unit 19C
Open savanna
6
1999
2009
Unit 2
Dry prairie
7
2004
2014
Unit 2 PV Road cut
Dry prairie
10
1999
2008
Unit 3
Dry prairie
9
1999
2008
Unit 3A
Dry prairie
9
2001
2006
Unit 6
Dry mesic prairie
5
2002
2008
Unit 7
Dry mesic prairie
6
2002
2008
Valley
Wet mesic prairie
6
Average years to flower: 6.5
Total sites: 21




South Slope with scattered compass plants
Tall compass plant on the steep road bank. This is one of the driest parts of the site.
Top of the South Slope by the Far Overlook.
In addition to compass plant, little bluestem, pale purple coneflower and bur oak grubs and saplings


Now that compass plant is so well established, how long will it continue to thrive?

The work of Frank Gould, one of Norman Fassetts students at UW-Madison, is pertinent. In 1936 Gould did an extensive survey of prairie remnants of Dane County, using the original surveyor’s prairie map as a guide. Although most of the original prairie was gone, he found remnants of it along roadsides, railroad tracks, “little-used pasture land”, and “wastelands”.

Among other species, he recorded the presence of Silphium laciniatum in 156 localities, of which 150 “are within the bounds of the original prairie districts as outlined on the old [original surveyor’s] map.” See Gould’s map below.




From Gould, Frank W. 1937. The present status of Dane County prairie flora. M.A. thesis, University of Wisconsin-Madison. See also Gould, Frank W. 1941. Plant indicators of original Wisconsin prairies. Ecology Volume 22: 427-429.

The largest prairie area on Gould’s map is that north of Lake Mendota that was once known as the Empire Prairie. The outlines of this part of Gould’s map follow almost exactly my Empire Map done by GIS that was alsobased on the original surveyor’s map.  It seems evident that compass plant has continued to thrive in the prairie areas where it had been present in 1836, when the original surveying was done.

Thus, I conclude that as long as suitable remnant prairie habitat remains, compass plant will continue to thrive, but it is not able to move onto “new” ground, as so many other of the prairie plants are able to do. It especially suffers severely from grazing.

The South Slope bluff prairie is an interesting compass plant habitat. How can compass plant, a conservative mesic species with a “C” value of 8, do so well in this sort of habitat?


Scanning the South Slope recently, I saw a compass plant 5 feet tall in the middle of what should have been the driest area. I looked further and saw a few more, almost as tall. I started counting and found at least two dozen compass plants, all in flower, and all looking very healthy, scattered across the slope.

In retrospect, I should not have been surprised. When the NRCS Site Description team visited PVC in 2014, they showed me that the soil on our “rocky” slope was very deep. They were able to thrust a 7 foot long metal probe all the way to the hilt. This type of soil is called colluvium. Although its surface is about 1/3 rock, the rest is exposed loamy soil quite suitable for deep-rooted prairie plants. 

If you want to see these bluff prairie plants, take a walk along the South Slope on Pleasant Valley Road from the driveway to County F.

Here is the passage from Curtis on grazing: (Vegetation of Wisconsin 1959; page 426)
 “Prairies on wet-mesic, mesic, and dry-mesic sites are literally wiped out by grazing, sometimes with almost unbelieveable rapidity. About 1940, a large tract of virgin wet-mesic prairie adjacent to the Faville Prairie Preserve of the University of Wisconsin Arboretum, in Jefferson County, changed ownership and was subjected to heavy grazing under cattle and horses by the new management. During the first summer, the animals proceeded to attack the species of highest palatability, with the very abundant plants of Silphium terebinthinaceum and S. laciniatum sought out like hidden candy at a child's birthday party. By the end of the second year, no prairie species whatever were visible in the closely cropped sward, although many were no doubt present as underground roots or rhizomes. The obvious dominants were redtop grass (Agrostis stolonifera) and Kentucky bluegrass (Poa pratensis). Other portions of the same prairie which had been pastured for a number of years were dominated by the bluegrass, with lesser amounts of redtop and quackgrass, plus an occasional native plant of ironweed, sneezeweed, common milkweed, and high populations of the exotic dandelion, Canada thistle, and white clover. No traces of the prairie grasses originally present nor most of the prairie forbs were to be seen. This total destruction of the original prairie dominants by grazing is to be explained by comparing their growth habits with those of the invading exotics. The native grasses produce erect growing points which are clipped off by the cattle (Neiland and Curtis, 1956). The exotic species like bluegrass, however, have creeping rhizomes which send up individual leaves. Removal of the tips of the leaves causes no permanent harm, since the tissues are replaced by the meristematic region at the base of the leaf. The exotics thus have a tremendous advantage in the competition for space.”

Monday, July 23, 2018

Oak savanna restoration: a case study

This link leads to a Power Point that describes succinctly procedures for restoring an oak savanna area. Kathie and I presented this some years ago at a North American Prairie Conference but it never got on the Internet. I did some brief edits and turned it into a PDF. The slides are fairly self-explanatory.

The PDF is being hosted on the website I maintain as a tutorial on oak savanna restoration. Those who find this PDF via the blog might want to dig deeper into the website.

A restored white oak savanna at Pleasant Valley Conservancy; mid-summer. Note the absence of brush

Tuesday, July 10, 2018

Learning about weeds: a personal account


At Pleasant Valley Conservancy we have dealt with weeds in our prairie remnants, our restored oak savannas, and in the prairies we have planted in former agricultural fields. Each situation presented different problems and required different solutions.

I admit I was surprised when Paul West told us in the summer of 1997 that hand-weeding would have to be done on the South Slope. All we had done so far was cleared and burned Kathie’s Prairie. How could there be weeds already? Not woody plants, but herbaceous ones. Weeds he specifically mentioned were wild parsnip and sweet clover. Later, mullein and thistle entered the picture.

Obviously, our restoration work had not created these weeds. They had already been there. So it was not only woody vegetation that we would have to deal with. I finally got accustomed to the idea that weeding was one of the major activities of restoration ecology. And in natural areas, weeding was often hand work, although weeds could sometimes be dealt with by mowing or spraying.

Paul West spent 6.5 hours pulling primarily wild parsnip on Kathie’s Prairie in July 1997. In July 1998 he and Pat Schrader spent 16 hours. Again, mostly wild parsnip. In 1999 the hired crew pulled no weeds as this was the year the whole South Slope was cleared, and burned, but Kathie did a lot of weeding (see below). But in the year 2000, West, Schrader, Michler, Brown, and Nate Chisholm among them worked almost 1000 hours pulling weeds, almost all on the South Slope!

Although most of the weeding in 2000 was on the South Slope, weeding was also done on the County F and Pleasant Valley Road cuts. Also at a scrubby area at the corner of PV Road and County F (Unit 14), and Toby’s Prairie (quite a bit, as this was in its second growing season).

In the early years, all the weeds were pulled by hand. This requires a strong back and strong arms and shoulders. Most of the folks pulling weeds at PVC were young and strong, and seemed to have no trouble. However, as the weeds age their root systems get larger, and eventually they get to the stage where they really can not be pulled. A strong person will end up just breaking the stem near the base. This is when you start thinking about a shovel.

Kathie’s notes on early weeding: “June 8[1999]. KMB to farm. Cleared brambles and brush above K’s Prairie—v slow work: 3 hours—will allow prairie to climb higher” [up slope]
June 10. KMB to farm—HOT; worked on more brambles and brush on K’s Prairie; 3 hours
June 14, 99 GREAT WEATHER T and K clipped brambles and brush on K’s prairie for 1.5 hour (-3 hours)


6-15 [1999] K only, 4.5 hrs; Cut clover and pull parsnips ~2 hrs. Lots of clover in middle area(s) or rocky prairie. Lots to do! Cleared patch near SE corner of K’s prairie. Should extend work from here. Also lots of clover on road cut below K’s p. ~2.5 hrs—cleared more @ top of K’s prairie

6-17[1999] K and T 4 hrs Sweet clover and Parsnips off road cut below K’s prairie…K: Cut clover, too hard to pull as so many (5-10) stems! Hope it doesn’t resprout. T: sweet clover and esp. parsnips along PV road

Aug 3, 99. K to farm. Willis here too…Most of sweet clover and parsnips now removed from whole area and Willis is pulling Q Anne's lace.

Aug 11 K to farm…Clipped brambles at base of K’s prairie and east 1.5 hrs

Broader weed activities
Kathie and I first got involved in invasive plants through our work at the Campus Natural Areas on garlic mustard. In fact, garlic mustard became a major issue for us for a while. Kathie discovered major infestations of garlic mustard in Shorewood Hills, and got a number of village residents involved. She got the Village Board to declare garlic mustard an official “noxious weed”, which led to lots of work in the village. Kathie organized volunteer work parties to control garlic mustard on village land, and she and I did lots of garlic mustard work on our own.

Then there was the very important meeting called “Plants Out of Place” (acronym POOP), held in March 2001 at Eau Claire. This meeting was held in association with meetings of The Wild Ones (the day before POOP) and The Prairie Enthusiasts (the day after POOP). With all these meetings, attendance at POOP was over 600. Kathie and I attended both the POOP meeting and the TPE meeting. I really revel in this sort of high-level meeting that provides a great summary of expert scientific information.

In addition to the meetings, there was an extended discussion among the presenters and attendees of how control of invasive plants could best be accomplished. This was one of those sessions where people wrote topics on large sheets of white paper hanging around the sides of the room. One of the major “conclusions” was that a new organization was needed that dealt with invasive plants of Wisconsin.

All those interested in this idea were invited to attend an evening meeting to formalize this organization. Kathie and I attended this meeting. TNC’s Nancy Braker, who Kathie had worked with extensively, was the secretary of the meeting. I ended up sitting in the middle of the table, which led me to do a fair bit of talking. When it came time to select officers for the new group, I was asked to be President. Since Kathie and I were so heavily involved in our own restoration work, I declined, but volunteered to be Treasurer. Before the end of the evening, it was decided to call the organization the “Invasive Plants of Wisconsin” (IPAW). In order to incorporate we needed Articles of Incorporation, which were written that evening. The By-laws, needed to get non-profit status, were written later by the Board of Directors.

As Treasurer, my responsibility was to get the organization started. I took all the checks that had been written by potential members and on return to Madison made the application to incorporate with the Wisconsin Department of Financial Institutions. The fee to incorporate came from my personal checking account. IPAW was officially incorporated on March 8, 2001, just a week after POOP was over. Once I had the official name, I got a tax ID number from the IRS, started a checking account, and deposited all the checks. With a bank balance, I was now able to write checks. I rented a post office box at the Hilldale Station (Box 5274, which still exists). I checked the P.O. box for mail weekly, and was pleased to see checks coming in.

The membership list was being maintained by the Executive Director of The Wild Ones, so as checks came in, I deposited them and sent the names and addresses on to her. I wrote a thank you note to every new member. With the Board of Director’s help I put together the papers necessary for becoming a non-profit organization and sent them off to the IRS. In due course, the letter came back making us a 501-(c) 3 corporation.

The other activity I played a major role was getting a good web site for IPAW. One of the new members, Marsha Vomastic, had volunteered to set up the web site. She was an experienced web designer and she and I worked together. I wrote quite a bit of the website content. Although the design has now been updated, Marsha’s web site served IPAW well for many years.

Because I was so intimately involved in the creation of IPAW, I quickly became very familiar with the biology and control of Wisconsin’s invasive plants. With my strong scientific background it was no problem reading the scientific literature in this field. And we had our own Conservancy as a test case for control methods!

Here it is 17 years later and weeding is still necessary, although lots less than in 1998.

Weeding at Black Earth Rettenmund Prairie
Kathie and I became stewards of this fine prairie remnant in 2001. By that time we were beginning to understand sweet clover fairly well, and BE was heavily infested. In those early years, the patches were very large, and had to be mowed.

Sometime around 2009 or 2010 mowing was no longer necessary, but hand pulling is still essential. Although volunteer work parties are held regularly, the fact is that most sweet clover work at BE is done by hired help, although for about 10 years we also used paid interns.

At one time I thought we might be able to eradicate sweet clover from BE, but I no longer believe this. However, some  years it is worse than others. This year is especially bad.

Why is sweet clover so bad at BE when the prairie itself is so good? After the Nature Conservancy acquired BE Prairie, considerable effort was put into sweet clover control, but as the years went by, work focused more on brush control. In the year 2000 only 7 hours were spent on sweet clover control. If sweet clover is not eradicated, seed formation will occur, adding to the already rich seed bank. The main reason Kathie and I took over stewardship in 2001 was because we were concerned about the sweet clover problem at Rettenmund Prairie.

Contractor mowing sweet clover at Black Earth Rettenmund Prairie, July 2005

Saturday, June 30, 2018

Prairie and savanna plant species present at Pleasant Valley Conservancy before restoration


We were fortunate that in 1995-1997, before any restoration work had begun at Pleasant Valley Conservancy, several plant species lists were prepared by competent botanists. Later, after Kathie became more familiar with the property, she added more species.

I put these lists together and added quite a few other species that had been missed because they were in remote parts of the property or would not have been visible at the time of year when the original observations were made.

There were 307 species that were present before any restoration or seeding, which is impressive. Also, quite a few of these species are very desirable, with high Coefficients of Conservation (C values).

As part of my work on the history of PVC, I was interested to see where these species had been originally found, thinking that may give some idea of how they were able to hang on without human help. The table shows the principal locations, and lists the most interesting species.

In the very high quality 1990 air photo shown here the locations of the two largest prairies can be seen. Also there are quite a few smaller areas that had not (yet) brushed in.


Site
Species
Notes
County F road bank
82
Mostly savanna; a few also found in prairies, lots of golden Alexanders; important collecting site, especially for savanna species
North Woods
5-10
Large populations of Trillium grandiflora and large lady slipper orchid
Toby’s Annex
5-10
Flowering spurge, Missouri goldenrod, Showy goldenrod, little bluestem, Indian grass
Unplowed north side of what is now Toby’s Prairie
1
Large population of Baptisia alba
Kathie’s Prairie (Unit 1)
37
Lead plant, sky-blue aster, purple prairie clover, small yellow flax, fringed puccoon, short green milkweed, Agalinis gattingeri, violet wood sorel, small skullcap, blue-eyed grass, gray goldenrod, prairie dropseed, bird’s foot violet
Tom’s Prairie (Unit 4)
19
Lead plant, sky-blue aster, fringed and hoary puccoon, violet wood sorrel, prairie turnip, blue-eyed grass, prairie dropseed, bird’s foot violet, prairie violet
Remnant area of Unit 11A
2
Lead plant, New Jersey tea
White Oak Savanna
1
Large population of shooting star
Unit 18
4
Virginia wild rye, spiderwort, white baneberry,  red baneberry,
Wetland
>100
No seeding has been done; sweet Indian plantain, glade mallow, swamp milkweed
Oak savanna areas
various
poke milkweed, purple milkweed, spikenard, wild sarsaparilla,

In addition to these larger sites, a number of smaller prairie remnants existed at Pleasant Valley Conservancy at the time restoration work began. Most of these were areas that had not been plowed, or had been too far from the barn for much grazing. Some of these remnants were important because they were the sources of seeds of particular prairie or savanna species.

Seeing this summary makes one realize that there is good hope for many other so-called degraded sites!



A detailed study of the 1990 air photo is interesting. Many south-facing hillsides like this one had at this date been completely covered with red cedar, which is very invasive and spreads rapidly. Why is this slope still fairly open?
  
The photo was taken before leaf-on, so the only green seen are conifers. However, almost all of these conifers were red pines that had been planted by a former owner. There were a few red cedars, but only scattered. I think the presence of the pines had kept the cedars from taking hold. And the rest of the vegetation on the south-facing slope was deciduous, either shrubs or trees.

We began clearing this hillside in the winter of 1997-1998 and finished it in 1999-2000. Now with many burns and extensive seeding, it is a highly diverse tallgrass prairie!


Air photo taken April 13, 1990 (from Dane County Regional Planning Commission)