Upcoming seed planting plans

It's still a long way to April, but it doesn't hurt to think ahead. We've got lots of seeds in the barn, waiting to be planted as soon as our spring burn season is over. Last fall we made a list of areas to be planted, with acreages, so that we would know how to make our seed mixes. The table below was the result.

As can be seen, most of the areas to be planted are small. We are finished planting large fields to prairie. But a number of problem areas remain.

The sunflower areas are those where there were solid clones of Helianthus divaricatus, which had essentially crowded out all other species. These were mostly small, but not so small that one could wait for them to get colonized spontaneously. Although the sunflowers are gone (due to use of herbicide), this species grows so dense that nothing else can compete. Who knows what the seed bank under these is? Depending on where they are, they will be getting either the dry-mesic or oak savanna mix.

Another problem, as those who have read this blog know, has been pale Indian plantain (Arnoglossum atriplicifolia), another native but very aggressive clone-former.

Most of the other areas in the table below are locations where sumac or other brush had been removed, and were fairly bare of "good" plants.

The seed mixes are all made. As soon as the land has cooled after the spring burns we'll be planting.

Unit	Description	Acreage	Type
Valley Prairie	Road cut	0.3	DRY-MESIC
Toby’s N at E end	Sunflower area	0.3	DRY-MESIC
7	E of Hickory Ravine/near Unit 18	0.5	DRY-MESIC
8	Bare area on S side	0.2	DRY-MESIC
10	Pale Indian plantain (PIP) area along woods road	0.2	DRY-MESIC
11A	Another PIP area along saddle road	0.4	DRY-MESIC
11A	Brush cut areas off side road and off woods road	0.5	DRY-MESIC
12B	W end of Toby’s	0.2	DRY-MESIC
12A	Sunflower area along gravel road	0.1	DRY-MESIC
20	By gate and PV road cut	0.1	DRY-MESIC
20	E end of Pocket Prairie	0.1	DRY-MESIC
Total	Dry mesic acres	2.9	DRY-MESIC
Cty F road cut		0.5	OAK SAVANNA
Triangle		0.1	OAK SAVANNA
6/9	Gully above big bur oak	1.0	OAK SAVANNA
5	Below S fire break	0.5	OAK SAVANNA
7	Hickory Ravine	0.3	OAK SAVANNA
10	Sunflower clone	0.1	OAK SAVANNA
11A/D	PIP area along Mid Savanna Trail	1.0	OAK SAVANNA
11D	Sunflower area	1.5	OAK SAVANNA
12A	Big Sunflower clone	1.5	OAK SAVANNA
13A	Sunflower area	0.6	OAK SAVANNA
19D	Sunflower area	0.1	OAK SAVANNA
Total		7.2 acres	OAK SAVANNA

Early air photos now available; useful for planning restorations

For years I have been using the early air photos taken by the Soil Conservation Service for planning restoration work at Pleasant Valley Conservancy. The first air photos for Dane County were taken in 1937, and show the property as it was at a time when farmers were still using annual fire. This air photo, and its interpretation, are shown on the PVC web site at the following link.

When I was starting out, these photos could only be acquired at considerable expense from the U.S. National Archives, although Robinson Map Library in Science Hall had a complete set for Dane County. Now, miracle of the Internet age, all these early air photos for the whole state of Wisconsin have been scanned by UW Digital Collections and are available for viewing and download through the State Cartographer's Office. Here is the link.

When you open this web site, you get a map of the whole state, and can move to and zoom in on any location. The base map here is a recent air photo, so you can see your land as it is today. You can key in the location you are interested in, or pan and zoom to it. Once you get there, you will see a series of dots, each with its code for the 1937 photo. Select the one you want and a preview screen appears on the left. You then have the option of downloading that photo at one of three resolutions: 150, 300, or 600 dpi. I would recommend using the low-resolution version first to be sure you have the correct image, and then download the 600 dpi version, even though it is a large file and downloading takes some time.

Just for fun, I downloaded the 300 dpi version for the area that includes the Schurch-Thomson site of the Prairie Enthusiasts. I then opened it in Photoshop and cropped to the area of interest, and then reduced the resolution so that it could be downloaded fast for this blog. Even with this low resolution, you can get some useful information. For instance, the site was mostly treeless, although there are areas around the barn (and the old house that has now been demolished) that have trees. This version is shown below.



I strongly recommend that anyone who is doing (or planning) a restoration download the relevant air photos for their property.

Why? See my earlier post on legacy effects!

A nice oak savanna burn

I spent some time scouring my hard disk to find a summer photo that was taken at the same location as the great savanna burn photo from the last post (now shown on the PVC web site). After a bit of digging (I ended up using Google's Picasa since it had nice tiny thumbnails), I found one that works well. See the composite posted here. The burn photo was taken on March 19 and the summer photo on September 13. Obviously, the trees and prairie suffered no damage.

Restoration of grazed oak savannas

Many remnant oak savannas are grazed or have been grazed in the past. As I have pointed out elsewhere, if the open-grown oaks are still present, these are prime candidates for restoration. If the savanna has been heavily grazed, there is probably little "good" herbaceous understory (grasses or forbs), and the best thing is to kill off the remaining understory with herbicide and start over, such as one does when planting prairies into ag fields. However, many oak savannas are not heavily grazed, and a less drastic approach may be possible.

Recently I discovered a fascinating article by Christopher Bronny, who was a junior high school teacher in Illinois. ("One-two punch: grazing history and the recovery potential of oak savannas." Restoration and Management Notes Vol. 7, no. 2, Winter 1989, pp. 73-76). Bronny had access to a site in Knox County, Illinois which had been grazed, but had outstanding open-grown bur and white oaks. He was able to fence off 3.7 acres. Surprisingly, a number of "good" savanna species came back quickly, including purple milkweed! Later he found lots of savanna and prairie species coming up. By the second year, he knew this site had strong potential for recovery when Turk's-cap lily, pale spiked lobelia, pale Indian plantain, New Jersey tea, red milkwort, white prairie clover, early buttercup, violet bush clover, yellow star grass, short green milkweed, false Solomon's seal, frostweed, showy tick trefoil, woodland sunflower, Short's aster, early and gray goldenrod, heath aster, little bluestem, Canada milkvetch, and hazelnut all cropped up.

"Obviously the vigorous response of these plants once grazing ceased demonstrates the tolerance to prolonged grazing. But how long they will survive grazing, and how survival is related to grazing intensity remains unclear."

Bronny uses the term "cryptic" to refer to these species, because they weren't visible as long as the cows were on the site, but were obviously ticking along in a repressed site. And of course, there are species that are very sensitive to grazing and would be long gone, such as compass plant and lead plant.

In some ways, a grazed site may be preferable to an abandoned site. Once the cows are gone, brush arrives in a major way, and shades out the understory. But grazed sites generally remain fairly open.

The possibilities for oak savanna restoration are endless.

January brush cutting at Black Earth Rettenmund

Now that the snow has settled down, it is possible to start brush cutting again. Saturday morning Willis, Kathie, and I made a threesome at the top of the North unit of Black Earth Rettenmund Prairie. Our main target was prairie willow, which threatens to take over the top of the hill. But any small shrubs we could find were fair game. We also cut small patches of gray dogwood and sumac, and the occasional aspen sapling.

The technique is simple. Willis used the Stihl with a sharp blade to cut the willow patches close to the ground and Kathie and I came along behind treating all the cut stems. The paint stick technique was ideal for this, especially since the willow patches were multiple stemmed (often 20 stems or more). We treat with Garlon 4 in oil, which has the added advantage that we could basal bark any stem that Willis missed.

What is this prairie willow (Salix humilis) that is giving us so much trouble? It is native, of course, and grows only a few feet tall. Why should we be worrying about it? Since it is fire-sensitive, and we burn the North unit every other year, it should never get too large. Right? However, in the last few years, despite the burns, it has really spread, and now threatens to take over the knoll. Since this is an area with lots of nice plants (seneca snakeroot, butterfly milkweed, wood lily, etc.), we want to keep it under control.

When Nature Conservancy acquired Black Earth Rettenmund Prairie in 1986, in the area we were working there were some quite large woody areas, including a major aspen clone. Despite the years of restoration work (almost 25 years now), the "memory" of these big shrubs and trees persists, and it is one of the areas where brush control is a perennial battle.

Military Ridge Prairie Heritage 2011 Calendar

The 2011 Military Ridge Prairie Heritage Calendar is now out, and has some nice photos of southwestern Wisconsin prairies and savannas. This is an attractive calendar that Katie Abbott has been producing for the past few years. The images are all from local photographers in the Military Ridge area.

We are pleased that several of the photos used came from our Pleasant Valley Conservancy crew. Amanda has a nice fall-color view of the south-slope savanna, Susan has an interesting photo of our November 2010 north woods burn, and Kathie has photos on three separate months: a birds-foot violet bloom on "Kathie's Prairie", a winter snow scene of the White Oak Savanna, and a great mid-summer image of Black Earth Rettenmund Prairie.

This calendar can be used as a simple guide to management, since there is a section each month on suggested work projects. Also some phenology data, plus an extensive table of dates for seed-collecting.

This calendar has been funded by the J.F. New Foundation, the Nature Conservancy, the Prairie Enthusiasts, and the U.S. Fish and Wildlife Service. Thanks, Katie, for a job well done!

An interesting western savanna type

Although we are restoring a midwest oak savanna, my interest extends to oak savannas in other parts of the country. In posts last year, I described visits to Emory oak savannas in the mountains of southeastern Arizona.

Recently I learned of another oak savanna ecosystem that sounds interesting. This is the Garry oak (Quercus garryana) ecosystem of southwestern British Columbia and the State of Washington. It turns out that the Canadians have been doing quite a lot of work on this ecosystem, primarily on the southeastern part of Vancouver Island. Also, there has been some work on Garry oak savannas in the south Puget Sound region. An extensive savanna is present inside the Fort Lewis (near Tacoma, Washington) military base. The savanna here is maintained by frequent fires that are set off by military training activities. This setup sounds similar to the oak savannas inside Wisconsin's Fort McCoy, except, of course, the oaks and the understory species are completely different.

The Garry oak savanna is a fire-dependent ecosystem. It turns out that the Native Americans managed this ecosystem with fire, being especially attracted to the bulbs (for food) of the camas lily (Camassia quamash) that thrived in this system. After European settlement, fire was mostly suppressed, and these days mostly occurs as wildfires.

The Garry oak range extends from southern BC to central California, although it is most prolific in Oregon (where it is often called Oregon white oak). As the photo above (taken in Klickitat County, Washington) shows, this vegetation is an open-oak grassland.

There has been a lot of work on what the Canadians call the Garry oak ecosystem. There is a nonprofit organization called the Garry oak ecosystem recovery team (acronym GOERT), that is very active. Here is a link to their web site.

The Nature Conservancy has acquired and is restoring a Garry oak savanna called the Cowichan Garry Oak Preserve. This is near Duncan, BC on Vancouver Island.

We have a Camassia species here in the midwest that also lives in oak savannas. This is wild hyacinth (Camassia scilloides), also called eastern or Atlantic camas. I've been trying to get this handsome species established at Pleasant Valley Conservancy, but as yet no luck. However, the past year I managed to acquire some solid-looking bulbs, which I have planted in marked locations. We'll see.