Tom's Blog

Monday, May 30, 2016

Serious tree damage (windthrow) from storm 5-28-2016

We finally got the rain we wanted on Saturday afternoon (May 28 2016). Unfortunately, it was accompanied by extremely strong winds that did serious damage to trees at Pleasant Valley Conservancy. Kathie and I spent part of Sunday discovering just what sort of damage took place.

We have a lot of venerable oaks, both bur and white. The wind seemed to affect primarily bur oaks at the west end of the Conservancy, mainly at the top of the hill, although there were also some cherries and several shagbark hickories. The largest hickory at the conservancy came down (see photo here).

Largest hickory along the Mid Savanna Trail lost its whole top, converting this tree into a "snag".
This location is close to a large milkweed clone that provides prime Monarch habitat.
Fortunately, the milkweeds will be unaffected.
Most of the trees were not uprooted, but rather lost their tops. Some of them still retain enough living material to remain alive, but quite a few lost all living branches, remaining standing as snags.

The photos here give little idea of the extent of the damage, although they do show the type of destruction we observed. Kathie's notes, given below, give lots of details.

The gravel road should be clear in a few days, but the rest of the damage will have to wait, as we are in the middle of invasive plant season.

These big branches are from a large black oak that was standing exposed to the full brunt of the wind.
It lost its whole top and was converted into a snag.

The rest of the black oak shown above.
In the background is our prized bur oak, 280 years old.
Fortunately, it stands slightly downhill on the north side and was protected from most of the wind damage.
A small branch was knocked off.
********************************************************************************
Kathie's detailed notes

Here are my observations from the big storm that hit at PVC on Saturday, May 28, from about 4 to 5 pm.  Not a happy visit, all in all. But NOTHING we could have done to prevent it.

I will list what I saw in order as I travelled along the roads and lanes:

1. Nothing much in the lower areas, only several smallish branches from the black walnut at the entrance to the Pocket prairie, and a dead walnut down on the other side of the road.

2. Cherry tree down across gravel road between triangle and Unit 20.

3. Tree branch a little farther on, near first bluebird house.

4. Tree broken in 12A, down the hill from about the middle of Toby’s.

5. Giant dead oak in 12A blown down.

6. Can see tree down along mid savanna trail.  More later

7. Can see big branch/tree down in 11 D  ?  More later.

8. East overlook:  Big birch down across trail down to mid-savanna trail. Tore up root ball from E. overlook. Cedar tree blown over, leaning into other cedars.

9. Rocky Overlook:  South firebreak trail—cherry tree down near Rocky overlook.

10. BIG oak down in Unit 10 (along South Fire Break). [This one was uprooted!]

11. Also Unit 10:  Whole top of black oak across from oldest oak down across road.  Knocked relatively small branch off oldest oak. [See photo in this post]

12. Oak in middle of Unit 10 down: was one of two trunks.

13. Unit 8:  one/third of huge oak down. 

14. Unit 19A: small dead oak fell—#2338.

15. Ridge trail. Huge walnut in 19A fell to north—into other trees.  Also big dead birch fell across ridge trail. Also another birch, but not across trail.

16. South Firebreak: Unit 8, going east from Overlook:  2 big branches across firebreak.  Also 2 others nearby. One branch/tree down below that in Unit 5 (9?)

17. Unit 8: Dead walnut trunk leaning heavily into big oak.

18.  South firebreak, from Tom’s Prairie, going East along south firebreak:  2 oaks with branches down.  HUGE bur oak down right ON firebreak—big root ball.  Large basswood down below firebreak. Huge branch or half of oak down in Unit 10 and on firebreak.

19. North firebreak:  west of chairs.  Big oak down.

20.  Mid-savanna Trail  (see note 6 and 7):  small branches on trail.  HUGE hickory (#405) broke off at base. Fell mostly off trail, and just east of the big milkweed patch.

21. Broken tree farther along mid savanna trail. 

See also Kathie's Facebook page for her photos.

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

In the post given at this link there is a brief discussion of a straight-line wind called a derecho that happened some years ago. That storm mainly affected already dead black oaks that had been killed by oak wilt.

Friday, May 27, 2016

Eradication of invasive plants (2): perennials

This is the second of two posts on invasive plant control. Last week’s dealt with biennials.

The table at the end provides an overview of key perennial weeds and a summary of control methods.

Perennial weeds may start as seeds or from underground roots or rhizomes. The life span of perennials varies widely. Some last only a few years whereas others may last indefinitely. Because of their root systems, it is unlikely that a perennial will be eradicated by digging the plant up. Thus, permanent control of perennials almost always requires the use of an herbicide.

Eradication of most perennial weeds requires great effort and extended time periods, generally over a multi-year period. Neither fire nor mowing will eradicate any perennial weed, although these procedures may find good use along with herbicide.

Most of the weeds in the table are dicots and hence susceptible to broad-leaf-specific herbicides such as 2,4-D, clopyralid (Transline), metsulfuron methyl (Escort), and triclopyr (Garlon). The one monocot in the table, reed canary grass, is controlled by a grass-specific herbicide such as clethodim (Intensity). Under certain conditions it may also be possible to use a nonspecific herbicide for these weeds such as glyphosate (Roundup). Details on the manner of use are given in the herbicide label specifications.

In the rest of this post, I give our own experience for successful eradication.

Spotted knapweed This is more of a problem in dry, sandy areas. However, when our gravel road was redone about 6 years ago, the contractor brought in gravel that was contaminated with seeds of this species. Each year for the next few years we waited until it was in flower and then spot-sprayed each flowering plant along the whole roadside with aqueous Garlon 3A as a foliar spray. This was effective and by year 4 this species had been eradicated.

Spotted knapweed growing in contaminated gravel brought in for road repair


Canada thistle This is one of the few weeds that is listed by the State of Wisconsin as a noxious weed. As far as I know, it is the only thistle species that is a perennial. It forms an extensive underground rhizome system. However, it does not compete well with prairie plants so that it is often only a problem in the early years of a prairie restoration. In the early years of our restoration work, small or larger patches of this weed popped up in planted prairies or in open savannas. Some of the smaller (i.e. less than 6 feet) patches could be controlled just by mowing consecutively for several years at the time of flowering. Larger patches were controlled by mowing at flowering time and returning later to spray the resprouts with glyphosate or triclopyr. We haven’t seen Canada thistle at PVC for at least six years.

Crown vetch This is a very aggressive plant which is very difficult to control. It has an extensive rhizome system and the seeds, like many other legumes, are very long-lived in the soil. The key is to not let it get started. US Highway 18/151 is heavily infested (probably planted when the road was rebuilt) and it is now moving off onto some of the nearby county highways. I watched one nice prairie remnant over which I had no control get taken over by crown vetch over a period of ten years, despite frequent burns. At PVC we had a single patch of crown vetch pop up on the lower part of our south-facing slope. I have no idea where it came from. It is easy to spot when flowering, and I sprayed it immediately with Garlon 3A. It quickly died and has so far not returned.

Leafy spurge This is another plant that is troublesome along roadsides and is a potentially serious invader of natural areas. It has a deep tenacious root system and spreads rhizomatously. Fortunately, we have never had to deal with this nasty plant, although we see it spreading along US 14 between Middleton and Cross Plains. Currently, the recommended herbicide for leafy spurge is imazapic (Plateau), spraying twice in the growing season, late spring (before seeding) and in the fall just before a killing frost.

Birds-foot trefoil This legume was once planted extensively agriculturally and because of its long seed life (as bad as sweet clover!) it can be a problem in prairies that are being established on former cropped fields. It is not rhizomatous but forms a deep tap root from which stems arise that spread out along the top of the soil. Because of its low-growing character, it is hard to see until it flowers. We have been dealing with this in Toby’s, the Pocket, and Ridge Prairies since they were first established. Our procedure is to find the center of the plant and give it one or two brief spritzes with 20% Garlon 4 in oil. The plant should be dead within a week. Details of its ecology and control can be found in my earlier post.

Reed canary grass (in upland sites) Reed canary grass is a major problem in wetland systems but does occur occasionally in upland sites. We have been dealing with this in some of our savannas for at least 15 years. It generally occurs as relatively small patches which can best be found at the time of flowering. Spray each patch with Intensity. If that herbicide is not available an alternative is to cut with a hand clippers each plant about six inches to a foot above the base, tie the stems together in a bundle, and use a spray bottle to treat the cut stems with 50% Roundup. This is a fairly time consuming procedure but is effective.

Motherwort This perennial is primarily a problem in heavily disturbed areas. It appears fairly early in the spring, before most native species are still dormant, and should be sprayed with foliar glyphosate or a broad-leaf specific herbicide.

Latin name
Common name
Growth
Severity (1)
Control methods
Centaurea maculosa
Spotted knapweed
Biennial or short-lived Perennial
Especially dry prairies and sandy habitats; more serious in western states; don't let it get started!
Spring and fall spray with broad-leaf-active herbicide
Cirsium arvense
Canada thistle
Perennial
Moderate; generally outcompeted in well established prairies; don't let it get started!
Spring spray with broad-leaf-active herbicide; summer mow; fall spray with broad-leaf-active herbicide
Coronilla varia
Crown vetch
Perennial
Now a potentially serious invader of prairies and savannas; don't let it get started!
Spring and fall spray with broad-leaf-active herbicide
Euphorbia esula
Leafy spurge
Perennial
Now a potentially serious invader of prairies and savannas; don't let it get started!
Spring and fall spray with broad-leaf-active herbicide
Leonurus cardiaca
Motherwort
Perennial
Low
Broad-leaf herbicide
Lotus corniculatus
Birds-foot trefoil
Perennial
Moderate
Broad-leaf herbicide; longlife seed bank; difficult to eradicate
Lythrum salicaria
Purple loosestrife
Perennial
Low
spray with broad-leaf-active herbicide when found
Phalaris arundinacea
Reed canary grass
Perennial
Low
Spring and fall spray;summer cut followed by spray of cut stems
Trifolium repens
White clover
Perennial
Low; outcompeted in established prairies (except along edges)
Spring spray with broad-leaf-active herbicide
(1)    Severity refers to prairies and savannas only. Wetland habitats will be different.

Saturday, May 21, 2016

First "official" Monarch sighting in Wisconsin at Pleasant Valley Conservancy

According to Prof. David Hogg, Monarch specialist at UW-Madison, the first "official" 2016 sighting of Monarch butterflies in Wisconsin was made Thursday May 19 at Pleasant Valley Conservancy.

Here is the report: The first “official” 2016 sighting of Monarch butterflies in Wisconsin was made yesterday at Pleasant Valley Conservancy, specifically in the oak savanna habitat on the south facing hillside.  I’ve attached photos of the adult (female) and one of the eggs she deposited.  We (Cameron Fullerton and me) watched her flit from milkweed to milkweed, and it appeared that she laid eggs on a dozen or more stems.  We examined a number of milkweeds after she left, attempting to target those she had visited (not easy to do with the large number of milkweed stems in the patch) and were able to find four of her eggs on stems ranging from 4 to 9 inches tall.

The sighting was recorded with the Southern Wisconsin Butterfly Association  <https://wisconsinbutterflies.org/butterfly/sightings>.

Monarch season has begun!
Monarch butterfly on shoot of common milkweed (Asclepias syriaca). David Hogg photo

Monarch egg on milkweed leaf. David Hogg photo

Those interested in helping further the Monarchs at Pleasant Valley Conservancy are invited to be volunteers Sunday May 22, 2016 from 10 AM until 4 PM (or any fraction thereof). We will be planting swamp milkweed and meadow blazing star "plugs", favorite Monarch plants.

Friday, May 20, 2016

Monarch butterfly project at Pleasant Valley Conservancy: volunteers needed Sunday May 22, 2016!

Monarch butterflies need all the help they can get! Pleasant Valley Conservancy (PVC) has lots of Monarch habitat, but more is  needed to replenish the diminishing populations of these important and attractive migrating insects.

At PVC, thanks to Kathie's efforts, we have been awarded a grant from the U.S. Fish & Wildlife Service to encourage Monarchs. Among other things, this grant has supported the purchase of seedlings of two important Monarch plants: swamp milkweed (Asclepias incarnata) and meadow blazing star (Liatris ligulostylis).

Volunteer help is needed to plant these seedlings.

Meet at the PVC Barn at 4609 Pleasant Valley Road. Hours are from 10 AM until 4 PM. Bring your lunch. Drinks and desert will be provided.

For information, call Kathie at 608-238-5050.


Monday, May 16, 2016

Invasive plants (weeds) eradication (1): biennials

This is the first of two posts on weed control. It deals with biennial plants. The second post on perennials will be made next week. The table at the end of this post provides a survey of all the invasive plants that are potentially a problem in the Upper Midwest area.

It seems unfair that as soon as nice plants are blooming in our prairies and savannas that invasive plants are also thriving. Unfortunately, we can’t let the invaders get ahead of us!

Biennial plants grow from seed their first year but do not flower. The cold period during overwintering induces flower bud formation and the second year they send up flower stalks and set seed.

Whether biennials are a problem in restoration ecology depends to a great extent on whether a seed bank exists and how long their seeds remain alive in the soil. Although there is little information on seed bank longevity, for many purposes it may prove best to assume that the life in the seed bank is extended. Thus, it makes sense to always assume that there will be an overwintering seed bank and that new plants will be appearing the following growing season. If they don’t show up, consider that a bonus!

The control cycle for a biennial like garlic mustard runs something like this:

First-year plants
  1. First-year plants at the seedling stage may be visible sometime in April-May. While they are still at the cotyledon stage they can be killed by fire. This is best accomplished with a propane torch carried on a backpack.
  2. First-year plants past the cotyledon stage are generally mixed in with native species and will be hard to find until late in the summer/early fall. They remain green long into the fall, making them visible when native species have senesced and turned brown (late November or anytime in December before snowfall). Since there are no green native plants at this time, spraying with glyphosate is preferred since this herbicide has no soil residual. The plants will not show any response to the herbicide, but will not come up the following spring. This is a very effective time to deal with first-year plants since all first-year plants controlled in the fall will not have to be dealt with the following year.
Second-year plants


  1. Most effort on garlic mustard focuses on second-year plants. Spray new growth in early spring as soon as the plants are large enough to find, using a broad-leaf active herbicide.
  2. The earlier spraying can be initiated, the better.
  3. Return at weekly intervals, or more often if good growing conditions exist (depending on the weather).
  4. Flowering plants that were missed, or flowering plants discovered too late to spray should be mowed with a brush cutter or hand-pulled before they set seed. Arguments exist about whether pulled plants will go on to make viable seeds if they are just laid on the ground. Most cautious people assume that flowering plants will go on to set seed and thus bag them for disposal in a land fill.
  5. Once plants start to form seeds they should definitely be bagged.
  6. The area should be canvased at weekly intervals until the end of June, removing all flowering plants.
  7. It is vital to prevent any plants from making and dropping viable seeds.
  8. Experience has shown that eradication of garlic mustard requires many years, but it can be done.
Wild parsnip


Wild parsnip is generally easier to eradicate than garlic mustard. The same techniques are used, although the timing is different.

Sweet clover
            Sweet clover is probably the most expensive weed that we deal with in prairie restoration work. In contrast to garlic mustard, the control cost per person hour per acre is quite high, and most infested areas are almost impossible to eradicate. It is found primarily in prairie remnants, as a legacy of their former use as pastures. The seed bank can remain alive for many years, and seed germination is stimulated by fire. I discuss the history of sweet clover in the UpperMidwest in this post:


First-year plants
1.     Very difficult to find early in the growing season, as they are small and delicate.
2.     In late fall, after native plants have senesced, they will still be green and can be sprayed with glyphosate. This is very effective, but areas sprayed must be monitored in subsequent years.
Second-year plants
1.     Begin control as soon as significant patches are found, usually mid-June or early July in the Upper Midwest. From then on, sweet clover will probably continue to appear throughout the summer.
2.     Scattered plants should be hand-pulled or dug using a shovel (a Parsnip Predator is ideal). The whole site should be canvassed biweekly until fall.
3.     Sweet clover is often found in large patches, even up to several acres, making hand pulling not really an option. Wait until all plants are in flower and mow, either with a brush cutter or a tractor. Timing of mowing is critical. If too early, plant stubs can resprout and flower. If too late, the cut flowers lying on the ground can set seed.
4.     Return to mowed areas within a week or two and hand pull those plants that were missed.
5.     Sweet clover forms a long tap root, and when hand-pulling, it is important to get the whole root. There are dormant buds at the base of the stem which will start growing if the stem is broken without getting the root.
6.     A strategy that has worked well is to pass through each unit at least once a week, pulling all visible plants. In seriously infested areas, monitoring weekly from early June until the end of July, then returning in September when there is often a resurgence of smaller flowering plants. Never allow seed formation to occur.
7.     Once sweet clover control has started, it must be continued annually, because if any sweet clover plants are left to set seed, the initial control efforts will have been wasted.

Japanese hedge parsley
About 20 years ago this was considered a newly emerging noxious weed. Unfortunately, it is now well established, at least in the southern part of the Upper Midwest. Hedge parsley is probably more difficult to eradicate than garlic mustard, but is less noxious and hence is often overlooked.


Hand-pulling is the preferred control method although spraying with a broad-leaf-specific herbicide will also work.

The severity given in the table below is for prairies and savannas. Wetlands are different!

Common name
Growth
Severity]
Control methods
Alliaria petiolata
Garlic mustard
Biennial
High; mainly in shadier areas
Spring and fall spray; hand pull; don't let it get started!; eradication takes years
Arctium minus
Common burdock
Biennial
Low
Spring spray with broad-leaf-active herbicide
Cirsium vulgare
Bull thistle
Biennial
Low
Hand pull, dig or spray with broad-leaf-active herbicide
Daucus carota
Queen Annes lace
Biennial
Moderate; generally outcompeted in well established prairies
Hand pull, mow, or spray with broad-leaf-active herbicide
Dipsacus laciniatus
Cut-leaved teasel
Biennial
Low
Hand pull, mow, or spray with broad-leaf-active herbicide
Dipsacus sylvestris
Common teasel
Biennial
Low
Hand pull, mow, or spray with broad-leaf-active herbicide
Hesperis matronalis
Dames rocket
Biennial
Low
Hand pull, mow, or spray with broad-leaf-active herbicide
Melilotus alba
White sweet clover
Biennial
High
Hand pull, mow, or spray with broad-leaf-active herbicide first-year plants in fall; long-life seed bank; eradication very difficult
Melilotus officinalis
Yellow sweet clover
Biennial
High
Hand pull, mow, or spray with broad-leaf-active herbicide first-year plants in fall; long-life seed bank; eradication very difficult
Pastinaca sativa
Wild parsnip
Biennial
High
Hand pull, mow, or spray with broad-leaf-active herbicide; can be eradicated with hard work
Verbascum thapsus
Mullein
Biennial
Moderate; establishes on bare ground; generally outcompeted in well established prairies
Hand dig or pull; late fall spray with broad-leaf-active herbicide or glyphosate
Torilis japonica
Japanese hedge parsley
Biennial or winter annual
Moderate; mainly in shaded areas
Hand pull, mow, or spray with broad-leaf-active herbicide; difficult to eradicate
Centaurea maculosa
Spotted knapweed
Biennial or short-lived Perennial
Especially dry prairies and sandy habitats; more serious in western states; don't let it get started!
Spring and fall spray with broad-leaf-active herbicide
Cirsium arvense
Canada thistle
Perennial
Moderate; generally outcompeted in well established prairies; don't let it get started!
Spring spray with broad-leaf-active herbicide; summer mow; fall spray with broad-leaf-active herbicide
Coronilla varia
Crown vetch
Perennial
Now a potentially serious invader of prairies and savannas; don't let it get started!
Spring and fall spray with broad-leaf-active herbicide
Euphorbia esula
Leafy spurge
Perennial
Now a potentially serious invader of prairies and savannas; don't let it get started!
Spring and fall spray with broad-leaf-active herbicide
Leonurus cardiaca
Motherwort
Perennial
Low
Broad-leaf herbicide
Lotus corniculatus
Birds-foot trefoil
Perennial
Moderate
Broad-leaf herbicide; longlife seed bank; difficult to eradicate
Lythrum salicaria
Purple loosestrife
Perennial
Low
spray with broad-leaf-active herbicide when found
Phalaris arundinacea
Reed canary grass
Perennial
Low
Spring and fall spray;summer cut followed by spray of cut stems
Trifolium repens
White clover
Perennial
Low; outcompeted in established prairies (except along edges)
Spring spray with broad-leaf-active herbicide