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| Tom's Journal (Blog)
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| 10/30/2007 | Road Work The savannas at Pleasant Valley Conservancy are on the top of a long ridge that extends about 3/4 mile. The top of the ridge is 200 feet above the town road. For much of our management work (burns, tree and brush removal, etc.) we need to be able to drive to the top of the ridge. The road we use was formerly a farm road that we have improved from time to time. Because of the steep terrain, there is a problem with washout. Road work takes a lot of equipment and requires careful attention to detail. It also requires hauling a lot of gravel to the top of the ridge.Unfortunately, the trucks that bring in the gravel are huge, and our road is narrow and steep. In the past, the gravel truck dropped its load at the bottom of the hill and the contractor had to haul it up with a front-end loader, a time-consuming job. After a field check and some discussions between the contractor and the gravel hauler, the latter decided to try to drive the gravel truck to the top. Wrong decision! The gravel truck had a "mind" of its own. Half-way up, the road has a side slope, which is where the gravel truck started to slide downhill. It took a Caterpillar tractor and another dump truck to rescue the gravel truck from disaster. Road work will continue tomorrow.
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| 10/27/2007 | Dealing with Walnut Resprouts on the Crane Prairie The Crane Prairie is only in its second growing season, and has a ways to go before we will be satisfied with it. The link above gives some of the background. Among other things, there were dozens of walnut trees, some fairly large. Herbicide treatment kept most of them from resprouting, but a few somehow escaped. This time of year, with most of the prairie vegetation in senescence, they were easy to spot. Since we plan to burn the Crane Prairie yet this fall, we had to deal with these resprouts now, otherwise they would be top-killed by the burn and could then not receive herbicide treatment. Walnut is a fairly soft wood and the resprouts are easy to cut with a brush cutter (see photo). 
From experience we have found that Garlon 4 in oil works better than glyphosate on cut stems of walnut. You treat the cut stem and then also spray around the stem collar, which makes the treatment like a basal bark. If we use a generous amount of spray on each cut stem (some of these walnut resprouts have a dozen or more stems), the walnut is really killed. It took Susan and Todd only half a day to deal with the walnuts in the Crane Prairie. |
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| 10/24/2007 | Attacking Small Buckthorn Many restorationists might be happy to have only small buckthorn plants to deal with, but when they have thousands, they might change their minds. We have been dealing with small buckthorn plants for most of the past ten years. They are what came up after we removed all the large buckthorn with basal bark treatment or by cutting and treating. Intially they probably came from the seed bank, but by now that must be exhausted. What we have are scattered plants with usually four or five stems per plant, sometimes more. Often they are not scattered, but occur in fairly dense patches. We have been trying multiple methods to eradicate these, and many of them work, part of the time. Some methods work better in the winter and some in the spring, but right now we are using a method that only works this time of year. This involves a foliar spray with trichlopyr (Garlon 3A) or glyphosate. The rationale is that at this time of year most of the "good" plants have died back or senesced, and thus should not take up herbicide. Buckthorn plants retain their green leaves for quite a while in the late fall, and might be sprayed without damaging the native vegetation too much. It is fairly straightforward to walk through a site and spot the buckthorn plants. Their dark green leaves really stand out. Each plant can then be zapped with a spritz of herbicide from a backpack sprayer. This is lots faster than cutting and treating, and hopefully will be more effective. I have staked out some test areas to verify this; I won't know until mid summer 2008 if my idea is correct. The main problem with this technique is that the "window" is only open for a short period of time in the fall. In another week or so, the buckthorns will have dropped their leaves. |
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| 10/21/2007 | Collecting Indian Grass Seed Last Sunday we had a nice group of volunteers collecting Indian grass seed. Unfortunately, the weather was drizzly, making the job onerous. This Sunday the weather was outstanding, but since we did not have another workday scheduled, we were on our own. Kathie and I spent several hours at this job. We collected in the Pocket Prairie, a tall grass prairie now in its eighth growing season. With the fine rains we have been having, the Indian grass was great, even though some of the seeds had been stripped from the heads by strong winds. You can really lose yourself in this tall grass prairie!
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| 10/20/2007 | Getting the Seeds Ready Once the seeds are collected, there is still a lot of work to do. Getting them dry is a major chore. Even if they seem dry in the field, they usually still retain a lot of moisture. If they are not dried properly, they will deteriorate, or get covered with mold growth. Our seed drying facilities are primitive, and only work for small amounts of seed. If you are collecting seed for a 40 acre planting, you need a different approach. Our small shop, once used for high-end wood working, has been given over to seeds. It is heated by an in-wall natural gas heater. The seeds are spread out on discarded children's sleds that sit on top of our power saw. The seeds are turned twice a day. For goldenrods and asters, it usually takes a couple of days of drying. Some other species take longer.
Once the seeds are dried, they must be screened to separate the seeds from the stems and chaff. This is a hand job that takes a lot of time. The set-up shown below consists of a homemade screen box that sits on the tile floor. The good stuff goes through the screening and the sticks are thrown away. Note that after screening, the seeds are not pure. There is lots of fluff and small debris. For our purposes, we can use these seeds directly, but if you want pure seed you need to do multiple screenings. The seeds are swept up with a dust pan and stored in brown paper bags. For large quantities, feed bags are used; they can be purchased at an agricultural co-op. The bags are stored in a cool, mouse-proof environment. For overwintering, we hang them from the rafters in our barn. It takes a lot of time to get these seeds ready for planting.
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| 10/16/2007 | The Underground Life of Buckthorn I'm determined to eventually get on top of the buckthorn problem! This is the time of year when spotting small buckthorn is fairly easy. Most of the native vegetation has turned yellow or brown but the buckthorn leaves remain green. We eradicated virtually all of our large buckthorn plants in 1998-2000, but new growth keeps coming up. Originally these probably came from the seed bank, but at Pleasant Valley Conservancy there have been no buckthorn plants mature enough to flower and set seed for many years. What are coming up now seem to be small shoots from rootstock that is scattered here and there in the savanna areas. These buckthorn are mostly in small patches of a dozen or so plants. These buckthorn patches almost seem clonal, yet I have never seen anything in the literature to suggest that buckthorn spread by rhizomes. After the recent rains I was able to hand-pull small plants, but I was after bigger game. I borrowed a device called a weed wrench and went after a larger plant.
The close up photo shows the impressive fibrous root system. The large gray structure toward the bottom of the photo is a horizontal root. The base of the shoot is visible in the upper right, along with two green leaves. The horizontal roots are long, and I have never succeeded in uprooting the whole structure. The root usually breaks off as the plant releases from the soil, usually after a few feet. I would like to know if the far end of the root has dormant buds that will become active after the shoot is cut. It seems likely, making the structure shown here a rhizomatous root. Certainly such a behavior would explain the formation of patches which buckthorn seem to make. I am very curious to know what happens to the herbicide molecules that we dab on cut stems! I have marked plants that I have cut and treated, and I know that there are no resprouts in the immediate vicinity of the cut stem. But how far is herbicide transported, and is the concentration high enough at the end of the rhizomatous root to prevent resprouting? Obviously, I've got to explore this whole problem further. And what a great research problem for a graduate student! This sort of spreading root system is apparently a common feature of woody plants (see Wilbur Duncan, 1935, Root systems of woody plants of old fields in Indiana. Ecology, Vol. 16, pp. 554-567). The roots of woody plants don't grow deep (like prairie plants) but spread widely. My next project is to use a shovel to dig up an intact root system. How far do these roots really travel? I also used the weed wrench on a honeysuckle bush. Honeysuckle does not show evidence of clonal growth, but it also has long spreading horizontal roots. The honeysuckle plant I dug is shown in the background in the weed wrench photo. The long root is in the upper right corner. In contrast to buckthorn, the honeysuckle root system is not fibrous. Although honeysuckles may often be found in large patches, they do not exhibit clonal growth. |
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10/14/2007 |
Seed Collecting in the Rain Sunday was a scheduled workday at Pleasant Valley Conservancy and we had an on-and-off light rain all morning. We worked any way, and ten intrepid souls showed up to help. Thank you very much! Our target was Indian grass and roundheaded bush clover. Neither of these is especially exciting to collect, but these are what we needed so we forged ahead. Some of the Indian grass had already been stripped away by last week's strong winds, but there was still enough left for our purposes. The seeds, of course, were wet, but they will dry eventually. At noon we had lunch in the barn, listening to the faint patter of rain on the roof. (In the barn the rain always sounds harder than it really is.) One of the enjoyable parts of a workday is the social aspect, and lunch is really conducive to interaction. The weather prognosis for the rest of the week is not good, but a sunny spell is promised for Wednesday afternoon. Hopefully, we can get some more work in that day. We still need dwarf and rough blazing star, among other things. |
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| 10/8/07 | Lion's foot seed heads
Although lion's foot (Prenanthes alba) is not uncommon inWisconsin, you rarely see it in large patches. Its flowers are fairly modest, but the seed heads really stand out, and make it easy to spot. At Pleasant Valley Conservancy this is strictly a savanna species. We have never seen it in prairie remnants, woodlands, or wetlands. As you might expect, this species appears on Brian Pruka's list of desirable savanna species. The color of the seed heads is due to the pappus, which is a collection of cinnamon brown hairs formed as part of the flower. Lion's foot is either a biennial or monocarpic, meaning that once the plant flowers it dies. Therefore, you never know where next-year's plants will turn up.
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| 10/7/07 | Ironweed seed collecting Seed collecting is fun, which is probably why our volunteer turnouts are better for that than for pulling weeds. One of the "tricks" of seed collecting is to know how to recognize the target plant from a distance. Some are easier to recognize than others. Ironweed (Vernonia fasciculata) is a handsome plant when in bloom (deep purple flowers) and is also fairly easy to recognize when in seed, as the photo shows.
Ironweed is one of those species that likes wet-mesic prairies, which is exactly where we find it. With the characteristic seedhead shape and color, one can spot a patch a long way off, even when there are other tall species. In the Barn Prairie and Valley Prairie we have a lot less ironweed than we do other members of the aster family whose seeds are ready now. But I found that I can spot an ironweed even when completely surrounded by these other plants. I have mentioned several wetland or wet-mesic species that we also find in our savannas. Ironweed is another example. In fact, the first place we found it was high on the south slope, not too far from a grove of savanna bur oaks, where we certainly didn't plant it.
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| 10/6/07 | Sweet Indian plantain seed collecting Sweet Indian plantain (Hasteola suaveolans) is a Special Concern species for Wisconsin. It is found only in the southwestern part of the state (Driftless Area). According to Cochrane and Iltis, its preferred habitat is marshy places along creeks and rivers, and wet prairies. They don't mention savannas, although we have one stand right in the midst of our bur oak savanna that we certainly did not plant. We have lots of sweet Indian plantain in our marsh and wetlands. A few days ago we were clearing out an area along Pleasant Valley Creek and found a lot of plants with seeds just ready for collecting. I put Sarah loose on this project and within a half hour she had two buckets full. We could have collected lots more. Obviously we don't need to plant any more in the marsh, but we'll throw it out along the edge of Crane Prairie, where it should grow. |
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| 10/1/07 | Woodland Sunflower Study In some earlier posts I moaned about the problem with woodland sunflowers. There are several species of the genus Helianthus that are potential problems. Almost all species of Helianthus are clonal, and spread very well by rhizomes. Many of our sunflower patches are in former wooded areas that contained open-grown oaks and were therefore converted to savannas. One might think that once one opens up an area where woodland sunflowers had been present they would no longer thrive, but unfortunately that is not the case. In many of our restored savanna areas large clones of woodland sunflowers are not only persisting, but spreading. I had one situation where some plants sent rhizomes under a four feet fire break into the Pocket Prairie, and proceeded to form several patches. These are invasive species! (Even if they are native.) I have tried several approaches to control them. A couple were based on techniques I have used for control of Canada goldenrod (Solidago canadense). This is also a clonal species, and tends to spread and take over in planted and restored prairies. One control method I used was to mow the goldenrod at the time of full flowering, with the idea that if most of the nutrients are in the stem, leaves, and flowers, the roots will be starved and die. This works with Solidago, but definitely not with Helianthus. Another approach with Solidago that worked even better than mowing was hand clipping. This not only got rid of the stems, leaves, and flowers, but did not mow down desirable plants hidden amongst that patch. These good plants were released and able to become established. This technique was also a complete failure with Helianthus. I recently returned to a test plot and found the sunflower patch completely re-established, presumably from dormant buds in the soil. There were no "good" plants present.
So far, the only way I have found to eradicate Helianthus is to spray with herbicide. Clopyralid (Transline) is very effective against members of the sunflower family, and will effectively kill the plants. However, I am not certain whether the whole clone is eradicated. I'll have to wait until next summer. One problem with use of clopyralid is that it is also active against many (but not all) desirable forbs. Grasses are unaffected, so that one should be able to kill the sunflower clone and plant the area with a prairie grass mixture. According to its label, clopyralid has a fair persistence in soil, so it acts as a pre-emergent heribicide as well as a post-emergent one. When woodland sunflowers first started to make themselves evident, soon after we had cleared areas for savanna restoration, I assumed that once they were in full sun they would die off. Else, why were they restricted to woodland areas? It is possible that given a long enough period of time, the sunflowers will die back in full sun, or be outcompeted by savanna or prairie species. So far, this hasn't happened to us. Perhaps I'm being too impatient, but then again, how much time do I want to wait? |
