Download Ecology

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Ecology
General Directions
Spend at least an hour, focused, exploring (or revisiting old haunts) in Schmeeckle Reserve.
Depending on your walking speed, allow at least 10-15 minutes additional travel time each way to
get from CNR to the Reserve and back. Try to balance extent of travel in the reserve with intensity
of observation.
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If at all possible, read the material below first, including the data sheets. That way, you can
spend most of your time actually studying the ecology of Schmeeckle Reserve communities
instead of stumbling down the trail reading the handout.
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Equip yourself with a PENCIL and ERASOR for most effective field note taking.
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Depending on circumstances, the visit might be a relatively structured class trip, or an
independent experience. In either case, collaboration with other students is really encouraged!
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Please stay on roads, trails, and boardwalks. You can get closer to nature by getting off the
beaten path, but the Schmeeckle Reserve communities simply can’t take the collective impact
of a campus full of students and professors trampling their seedlings, compacting their soils, or
in the case of lake and stream, stirring up their bottom.
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For the same reason, please don’t collect any specimens or even fragments except under the
specific advice of your professor.
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Your professor will also let you know about modifications in procedure or assignment.
Route Suggestions
A convenient place to start your trip, even to rendezvous with other class members, is the pavilion
where Reserve Street meets the reserve at the north end of campus. [Historical note: Reserve
Street had its name before there was a Schmeeckle Reserve! If you look closely, you can see
evidence that the street used to go straight north through what is now an intentionally naturalized
trail. The manhole covers and maybe the smell demonstrate that the sewer line still crosses the
reserve, and the fire plugs testify to the water line that is present. There are buried phone lines
too.]
The fireplugs don’t add much to natural esthetics, but they do make good reference points. There
are three, spaced about equally along the half mile span of the Reserve north of the pavilion.
Proceed north into the reserve, looking for wetlands communities at the south end, then uplands
communities further north. The second fireplug on the left, a full quarter mile north of the campus,
marks a contrast between relatively young woods to the south and Chilla Woodlot to the north.
Chilla Woodlot hasn’t been logged since around the turn of the century, and includes most of the
largest, oldest trees in the reserve. If you choose to concentrate your time in the northern part of
the reserve, you may come across upland openings on the otherwise continuous woods there:
one to the left (west) on a slight hill near North Point Drive, and one a short distance through the
woods to the right (east) over a narrow boardwalk.
Eventually, work your way east from the Reserve Street Trail over the University Trail boardwalk,
cross Michigan Avenue (four-lane, watch for cars!), and visit Joanis Lake. [Historical note: Joanis
Lake was excavated in 1977 to provide fill for the construction of the Sentry Insurance building and
to provide a lake for the campus. At this time, the part of Michigan Avenue that crosses the
reserve was built, first as a haul road for fill. Michigan Avenue has a somewhat self-contained
storm sewer, which at first was built in such a way that it began draining the Schmeeckle Reserve
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wetlands! Modifications to prevent this rapidly followed. The “naturalization” of Reserve Street was
undertaken to compensate for the environmental degradation caused by the extension of Michigan
Avenue.]
The lake itself is a groundwater lake with no input or output. [Historical note: When the lake was
excavated, the small creek to the east was actually detoured around the lake, to avoid likely
nutrient pollution . . . of the lake, not of the stream.] The surrounding terrestrial communities, like
most of the southern part of Schmeeckle Reserve, range from very wet to well-drained, depending
on how the weather has been recently as well as on alteration of ground water movement caused
by significant construction such as the Highway 51 bypass and the Sentry Golf Course.
If you return to the campus by walking west along Maria Drive, you’ll pass the fitness course. The
course and the rapelling tower are on a lobe of high ground that extended into the wetlands.
[Historical note: that high ground is the accumulation of Stevens Point street sweepings, which
were emptied there for many years before the reserve was established. As a matter of fact, both
the fields and dorms in the northern part of the campus are built on fill over former wetlands.] Much
attention was paid to enhancing the vegetation of the wetlands that interfinger with the fitness
course in an effort to make the site reflect the overall wilderness esthetics of the reserve.
Extensive plantings of wetland species were made, and the present vegetation represents an
interesting mix of pre-existing, planted, and newly arrived species.
Study Suggestions
The data sheets will ask you for observations on three different communites that you observe in
Schmeeckle. There is no set route for you to follow, but you should be alert to vegetation change
and try to visit some contrasting sites. Take notes on your observations or, if you’re really
organized, construct the observation sheet as you go.
No matter where you go look for evidence of the following:
 biological signs of the season
 different biological communities
 ecotones (boundaries or transitions between communities)
 environmental contrast between communities, especially moisture and shade
 kinds of plants, whether easily detected or not
 growth form of conspicuous plants
I. Ecological Seasons
Ecologists fine-tune the calendar from our standard four, three-month season. One such scheme
is the one below, modified from a system developed by a fine Illinois ecologist named Kendeigh.
Ecologists also pay particular attention to the springtime increase and fall decrease in the length of
the day, the photoperiod. The vital activities of many plants and animals are timed by
physiological reference to this natural calendar. At our latitude, days follow a sine-wave of length
from about 15 hours in late June to 9 hours in late December.
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II. Recognizing and Naming Biological Communites
Find a comfortable place where you can look at any vegetated part of Schmeeckle Reserve. Then
enjoy some time out of the building and think about what you’re seeing.
Ecologists view the organisms which occur and interact together in a particular place as biological
communities. (Then they argue about whether or not this is a good idea!) Look your surroundings
and see if you can see distinctions among communities. You might want to walk around a little if
you feel like you are in the middle of a single community with no others in sight. Examples of
communities that some have recognized in Schmeeckle Reserve are:
meadow
mixed hardwood/conifer forest
aspen grove
alder thicket
cattail marsh
vernal pond (dries up in summer)
lake
There are many other possibilities, though, and the only guidelines are those of biological insight
and common sense.
The big question is whether or not these communities are really natural entities, or just the
imaginings of humans who need pigeon holes to organize their thinking. The land plants of
Schmeeckle Reserve obviously stay put, but the animals come and go according to their instincts,
impulses, crises, and seasonal responses. We can see the influence of plant composition on many
the community names chosen above.
You obviously represent something more special that your individual organs considered
individually. Does Chilla Woodlot, as a community, similarly have capacities beyond the trees,
shrubs, herbs, insects, birds, mammals, fungi, etc. which make it up? (This is a thought question.
No written answer is necessary!)
IV. KINDS of Plants and their Niches (Ecological Occupation)
Vascular plants, which comprise most of the plant kingdom, have well-developed water- and foodconducting systems which give them the potential to grow large on land. Most of the conspicuous
plants in Schmeeckle Reserve are vascular. The lake ecosystem is an exception. Vascular plants
are the principal primary producers on the reserve and are at the base of many of its food webs.
Bryophytes, also members of the plant kingdom, are mostly photosynthetic land plants too, but are
non-vascular. For lack of a well developed system for moving water and food, they can never grow
much into the air beyond their source of water or deep into the substrate beyond their source of
light. In Schmeeckle Reserve, look for bryophytes especially on tree bark, in tree tops (good luck!),
and on rocks or logs which are high enough not to get covered by fallen leaves. Bryophytes are
numerous, but not very productive primary producers in Schmeeckle Reserve.
Lichens have an ecology very much like bryophytes, but are actually wildly different: each lichen is
composed of a fungus and a unicellular alga living collectively in a place where neither could
survive alone. In Schmeeckle Reserve, as elsewhere, lichens occupy sites similar to those of
bryophytes except they don’t do well in deep shade. Like bryophytes, they are numerous, but no
very productive.
Algae, unless in partnership with other organisms, are basically aquatic. Look for filamentous
algae in standing or flowing water. Too small to observe directly, many unicellular Schmeeckle
Reserve algae, especially diatoms, are lurking beyond the capacities of our vision in water and on
wet soil. Most of the primary production in Joanis Lake is accomplished by algae, though there are
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also some aquatic vascular plants. The algae are essential to the other organisms in the lake, both
as primary producers and in oxygen production.
Fungi literally permeate the logs, dead leaves, and soil of Schmeeckle Reserve. Their microscopic
threads ooze enzymes which gradually digest the litter. Other fungi parasitize living plants, and sap
their strength. Whether living by decay or as pathogens, the visible products of the fungi are likely
to be their fruiting bodies: reproductive structures such as mushrooms on a log or brackets on a
dead tree. The majority of the vegetation decay on Schmeeckle Reserve is accomplished by fungi.
Bacteria are the most numerous but the most elusive denisons of Schmeeckle Reserve. Their
tiny, isolated, chained, or clustered single cells can essentially not be seen without removing them
from their natural setting, then culturing them to increase their numbers. Their signficance, though,
is enormous. Most of the animal decay in Schmeeckle, and significant mineral recycling in the soil
result from the activities of bacteria. Along with viruses, bacteria significantly affect the health and
population growth of the fauna. Look hard for bacteria on the field trip today. Right.
Animals of the greatest variety inhabit Schmeeckle Reserve. Many of the most important largely
escape our attention. From a plant perspective, the especially significant non-human animals
include
herbivores:
mammalian browsers, grazers, and harvesters of fruits and seeds - look for them and sign
of their activity
different kinds of insects and other invertebrates specialized to utilize virtually any plant part
from fruits to seeds to buds to foliage to inner bark to roots
pollinators:
insects like moths, butterflies, bees, and beetles, each with their special passions, seasons,
and styles
seed dispersers:
birds, especially, but also all the other fruit and seed eaters, especially storers like
chipmunks and squirrels
recyclers:
a largely unseen world of soil dwellers who collectively accelerate the recycling of organic
material that bacteria and fungi complete: earthworms, mites, millipedes, insects, and
many more
V. FORM of Plants
The form of plants can tell us a lot about the year-round climate. The lack of trees in prairies,
deserts, and tundra reflect the climatic severity of such places. Leaf fall in Wisconsin autumn
reflects the deciduous nature of practically all our vascular plants. It is no accident that broadleaved, evergreen trees are largely confined to climates with no winter and no dry season.
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Growth Forms, with Examples
(forms rare in our climate are shaded)
TREES
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Larger woody plants, mostly well above 3 m tall.
needle-leaved (mainly conifers) SHORT THERMAL GROWING SEASONS spruces and firs DROUGHTY
SITES jack pine SWAMPS baldcypress, tamarack
broad-leaved evergreen (many tropical and subtropical trees, mostly with medium sized leaves)
FOREST CLIMATE WITHOUT SEVERE COLD magnolia
evergreen-sclerophyll (with tough, evergreen, mostly smaller leaves) HOT DRY SUMMERS, MILD,
MOISTER WINTERS live oak
broad-leaved deciduous (leaves shed in Temperate Zone winter or tropical dry season) FOREST CLIMATE
WITH COLD OR DRY SEASON sugar maple
thorn-trees (armed with spines, in may cases with compound, deciduous leaves) SEMI-ARID
CLIMATES Acacia
rosette trees (unbranched, with a crown of large leaves--palms and tree ferns) TROPICS, OFTEN
WHERE SOIL INFERTILITY LIMITS OTHER TREES coconut palm
bamboos (arborescent grasses) MILD TEMPERATE AND TROPICAL CLIMATES golden bamboo
LIANAS
Woody climbers or vines.
WORLD WIDE, BUT GREATEST IMPORTANCE WHERE ATMOSPHERIC ENVIRONMENT IS MILD AND
HUMID wild grape, in Wisconsin developed best along rivers
SHRUBS Smaller woody plants, mostly below 3 m in height.
 needle-leaved SIMILAR TO CLIMATE FOR NEEDLE-LEAVED TREES Canada yew, dwarf juniper
 broad-leaved evergreen SIMILAR TO CLIMATE FOR BROAD-LEAVED EVERGREEN TREES,BUT WITH
INCREASED RANGE INTO HIGH LATITUDES most hollies, Rhododendron
 evergreen sclerophyll HOT DRY SUMMERS AND MILD, MOISTER WINTERS AND NORTHERN BOGS!
leatherleaf, bog laurel
 broad-leaved deciduous SIMILAR TO BROAD-LEAVED, DEDIDUOUS TREES, BUT EXTEND TO HIGHER
LATITUDES AND INTO MORE ARID REGIONS sumac, hazlenut
 thorn-shrubs ESPECIALLY IMPORTANT IN SEMI-ARID SUBTROPICAL CLIMATES blackberry
 malakophyllous shrubs SEMI-ARID CLIMATES sagebrush
 rosette shrubs SEMI-ARID CLIMATES yucca, agave, aloe, etc
 stem succulents Cacti, certain euphorbias, etc. SEMI-ARID CLIMATES WITHOUT SEVERE COLD
prickly pear cactus
 semishrubs Suffrutescent, that is, with the upper parts of stems and branches dying back in unfavorable
seasons. CLIMATES WITH SEASONALLY SEVERE TEMPERATURE OR MOISTURE CONDITIONS sweet
fern, steeplebush
 subshrubs or dwarf-shrubs Low shrubs spreading near the ground surface, less than 25 cm high.
GROUND LAYER IN HIGH LATITUDE CONIFER FORESTS wintergreen, partridgeberry
Epiphytes Plants, vascular or not, which grow on other plants, but are not parasitic.
 BEST DEVELOPED WHERE AIR IS WARM AND HUMID ALL YEAR many orchids and bromeliads, including
Spanish moss, most Wisconsin epiphytes are bryophytes and lichens
Parasites Vascular plants which derive their food and water from host plants.
 ECOLOGY REFLECTS THAT OF HOST PLANT mistletoe, dodder
Herbs Vascular plants without perennial above-ground woody stems.
 ferns UNDER CANOPY OR WHERE ATMOSPHERIC ENVIRONMENT NOT VERY STRESSFUL interrupted
fern
 graminoids Grasses, sedges, and other grasslike plants. NOTABLY SUCCESSFUL IN STRESSFUL
ENVIRONMENTS, BUT NOT USUALLY VERY SHADE TOLERANT little bluestem
 forbs Herbs other than ferns and graminoids. VERY DIVERSE ECOLOGICALLY red clover, goldenrod
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Bryoids
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Moss-like plants without vascular system.
lichens SUCCESSFUL EPIPHYTES; NEED PERIODIC WETTING AND GOOD LIGHT British soldier lichen
mosses USUALLY DROUGHT SENSITIVE, SHADE TOLERANT hair cap moss
liverworts VERY DROUGHT SENSITIVE, SHADE TOLERANT Marchantia
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(table after Whittaker, R.H. 1976. Communities and Ecosystems, p. 62)