Story of a backyard open oak woodland: part 2

This is Part 2 of the saga of how we turned our small backyard from scrawny lawn to lush open oak woodland. Access Part 1 with this link.

Kathie and I live in the Village of Shorewood Hills and the word “wood” in the name is apropos. According to the early history of the village, there were open areas and then there were patches of woods that went back to presettlement times. The native trees are all oaks, mostly white (Quercus alba), although there are also some mature bur oaks (Q. macrocarpa). It’s a great area to live in, and although we have large branches hanging over the roof, so far we haven’t had any roof damage.

I think most gardeners would agree that you can’t get a good lawn if its too shady. After 36 years of mowing a scrawny lawn, and with lots of experience doing restoration work at Pleasant Valley Conservancy, we decided to turn our backyard into an open oak woodland.

Kathie started the conversion in the fall of 2011, so this is now the sixth growing season. The species list below shows 48 species, including 5 State-listed species. Pretty good, considering that the area is about 40 X 66 feet.

The original lawn was killed in the summer of 2011 with glyphosate and by late fall the ground was bare. It was planted with oak woodlands seed mix, and then hand-weeded the following summer. Each year a few new species have been added, and hand weeding continues.

Early summer 2012

Late summer 2017

The table gives the current flora. The only species on the list that might be questioned is the lily, whose identity is uncertain. This came from a former next-door neighbor, who did not like the color!

	Latin name	Common name	State-listed
1	Actaea alba	White baneberry
2	Actaea rubra	Red baneberry
3	Adiantum pedatum	Maidenhair fern
4	Agastache nepetoides	Yellow giant hyssop	****
5	Agastache scrophulariaefolia	Purple giant hyssop
6	Anemone virginiana	Woodland thimbleweed
7	Apios americana	Hot peanut
8	Aquilegia canadensis	Wild columbine
9	Arisaema triphyllum	Jack-in-the-pulpit
10	Asarum canadense	Wild ginger
11	Asclepias purpurascens	Purple milkweed	****
12	Aster lateriflorus	Calico aster
13	Aster novae-angliae	New England aster
14	Aster sagittifolius	Arrow-leaved aster
15	Bromus latiglumis	Ear-leaved brome
16	Campanula americana	Tall bellflower
17	Cimicifuga racemosa	Black cohosh
18	Cryptotaenia canadensis	Honewort
19	Elymus riparius	Woodland wild rye
20	Erigeron strigosus	Daisy fleabane
21	Eupatorium purpureum	Purple joe-pye weed
22	Eupatorium sessilifolium	Upland boneset	****
23	Geranium maculatum	Wild geranium
24	Hackelia virginiana	Stickseed
25	Hasteola suaveolens	Sweet Indian plantain	****
26	Hydrophyllum virginianum	Water leaf
27	Impatiens sp.	Jewel weed
28	Lilium spp	Trumpet lily
29	Mertensia virginica	Bluebells
30	Monarda fistulosa	Wild bergamot
31	Napaea dioica	Glade mallow	****
32	Osmorhiza longistylis	Smooth sweet cicely
33	Phlox divericata	Woodland phlox
34	Podophyllum peltatum	May-apple
35	Polygonatum biflorum	Smooth Solomon's seal
36	Prenanthes alba	Lion's foot
37	Ratibida pinnata	Yellow coneflower
38	Rudbeckia hirta	Black-eyed Susan
39	Smilacina racemosa	False Solomon's seal
40	Solidago flexicaulis	Zig-zag goldenrod
41	Solidago speciosa	Showy goldenrod
42	Solidago ulmifolia	Elm-leaved goldenrod
43	Tradescantia ohiensis	Common spiderwort
44	Trillium grandiflorum	Large-flowered trillium
45	Uvularia grandiflora	Bellwort
46	Veronicastrum virginicum	Culver's root
47	Viola soraria	Door-yard violet
48	Zizia aurea	Golden Alexanders

A good year for purple and white prairie clover!

The prairies have benefitted greatly by the extensive rains from mid June-late July. Especially, our dry prairies on the South-facing Slope are lusher than we  have ever seen them. Virtually all prairie species are thriving, but two species that are particularly fine this year are purple and white prairie clover (Dalea purpurea and D. candida ). Even before they bloomed there were large amounts of plants on the south slope (Units 2 and 3). A week ago, white prairie clover was in full bloom, and this week it is purple prairie clover, which, because of its color, is spectacular. You can actually tell these two species apart in the vegetative stage, since D. purpurea leaves are smaller and more delicate.

Both of these species are characteristic of dry prairies, with D. purpurea (C value of 7) being more common than D. candida (C value of 8). Since it is a nitrogen-fixing legume, D. purpurea is often added to seed mixes for CRP plantings, although I doubt whether this delicate species adds significant nitrogen to the soil.

D. purpurea was present at Pleasant Valley Conservancy on the south slope (the “goat prairie”; Unit 1) even before restoration began (1995-97), and we have spread it widely from collected seeds. D. candida was not here and was introduced from seeds collected at two high-quality prairie remnants

 

Purple prairie clover on the South Slope. Lots of other species are thriving on this slope, including compass plant, lead plant, spiderwort, and all the warm-season grasses. Note also the oak grubs.

Purple prairie clover

Controlling invasive plants: skills versus strategies

The skills needed to remove invasive plants are deceptively easy to learn. Cutting, pulling, digging, and girdling require little formal training. (That’s why volunteers can be used.) Even spraying is a straightforward activity.

However, the strategies involved are much more difficult. DANGER! If you use the wrong strategy you may be doing more harm than good, or at least may be wasting your time. In my 25 years of restoration work I have watched some strategies completely fail, most of which were applied out of ignorance.

Key strategies: Recognition, identification, timing, choosing the appropriate technique, (mechanical or chemical?), team organization. Knowledge and judgement are key.

Developing strategies: Start with knowledge of the bad actors, read the scientific literature, government manuals (but don’t assume they are infallible). Use the Internet judiciously. Especially avoid undocumented suggestions from others. (Lots of misinformation is passed around.)

Learn the important plant characteristics: monocot or dicot; Latin name; life cycle; clonality; habitat; phenology; annual, biennial, or perennial; herbaceous or woody.

Important items: Early detection monitoring, location maps, risk assessment (triage, see below), measurement (size of population; scattered, patchy, massive), identification, timing (season), choosing the appropriate technique, (mechanical or chemical; often combined).

Understand herbicide chemistry, biochemistry, fate in soil or environment. Read the label. Experiment! Mark your experiments with flags or stakes. With rare exceptions, you can’t eradicate invasive plants without at least some use of herbicides.

Nothing can replace extensive field experience! Get out there and take notes

Risk assessment (triage). Place the target into one of these 5 categories

1.     Eradicate everywhere

2.     Eradicate in high-quality areas

3.     Control spread

4.     Control if time available

5.     Ignore [can’t stand competition?]

Early detection is important

Set up a thorough survey method; AT DIFFERENT SEASONS OF THE YEAR!!

Use of a plant’s characteristics to help detect it: fall color; flowering (especially important); early appearance; size; habitat (prairie, savanna, woodland, wetland); legacy effects (history of the site).

Keep coming back to sites already restored, because it is almost certain there will be more plants to deal with, either plants missed or new growth. Don’t assume the site is clean! Unfortunate but true.

Don’t let the word “native” seduce you. Among others, sandbar willow, Canada goldenrod, and smooth sumac are native, but are generally “malignant” under present conditions.

For successful invasive plant control, a strong work ethic is needed. Get it done!

Don’t let these things happen:

·       You pulled the wrong thing.

·       You sprayed the wrong thing.

·       You worked at the wrong time.

·       You worked at the wrong site.

If you are using contractors, monitor them closely. Until they have a “track record”, it is best to have a manager on the site while a contractor is working.

Here is a link to a well thought-out strategy of invasive plant control, the BradleyMethod, first used in Australia.