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Natural vegetation occurs in distinct types adapted over time to
specific environments. Various vegetations can influence the soil
quite differently as noted in sign 14. The major types (Life Zones)
are:
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Forest
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Shrub*
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| Oak (dry) Forest* (everywhere)
Bur-Black-White-Red oaks, Black cherry, Shagbark hickory |
Old Field (Arboretum, Eagle Heights)
Bluegrass with invading oak forest shrubs and saplings |
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| Climax (mesic) Hardwood (Eagle Heights,
Maple Bluff) Sugar maple, Basswood, Elm, White ash |
Wet Meadow (drained or silted)
(Arboretum, Cherokee) pussywillows, Red osier dogwood |
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| River Swamp (Yahara and Wisconsin
river) Silver maple, Elm, Green ash, Swamp oak, Willow,
Hackberry |
Dredged Ditch-Bank & Shores (here,
Arboretum, farmlands) Willows, Boxelder, Elm, Cottonwoods,
Green ash |
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| Open-Dry |
Open-Wet |
| Short-lived Weeds (everywhere;
croplands; here; see signs 8,
22) |
Deep Marsh (here and by Picnic Point;
see signs 2, 3,
30) Cattails, Bulrushes |
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| Old Field, Pasture, Roadsides, Lawns
(everywhere) see sign 2. Bluegrasses and other
Eurasian and
American long-lived weeds |
Wet Meadow (Arboretum and Cherokee)
Tussock sedge and Bluejoint grass. If water rises, goes
to cattail; if siltation occurs, goes to ragweed |
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| Prairie (Arboretum restorations; see
signs 13, 20) relics; holds own especially with fire, but goes
to old field if disturbed |
Lowland Weeds (disturbed or drained
wetland) (Arboretum, farms, spoilbanks), Nettle, Giant ragweed |
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| Sand Barrens (Wisconsin River and
Arboretum) (some desert and prairie species) |
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*All three shrub communities and the oak woods are being invaded by
dense masses of Eurasian honeysuckles and buckthorns that gained
entry with livestock grazing. See sign 8 (29) for some common
native shrubs.
Settlement
has caused a great expansion of the weed floras, both native and
introduced (150 kinds), and the elimination of many native floras
(some 2,000 kinds), especially the prairie (320 kinds), removed
either by plow and cow, bulldozer and herbicides, or by forest
invasion if left unburned. Upland erosion, siltation in the deep
marshes, and drainage and grazing in wet meadows have allowed
invasion of all by shrubs, along with the Oak forests which are
slowly changing to maple with fire protection.
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