IOWA ACADEMY OF SCIENCE 
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Co. and the Iroquois Iron Co., there is an overlapping of the two above 
mentioned zones, so that separation is not as easily made. 
Belt (2) includes a number of new species of annuals and other 
herbs such as the following: goosefoot or lamb’s quarter ( Chenopo - 
dium album L.), pepper grass ( Lepidium apetalum Willd.), Lepidium 
virginicum L., blue vervain ( Verbena hast at a L.), horse weed (Eri- 
geron canadensis L.), evening primrose ( Oenthera biennis L.), five 
finger ( Potentilla canadensis L.), dandelion ( Taraxacum officinale 
Weber), Aster sp., yarrow ( Achillea Millefolium L.), sour dock ( Bumex 
crispus L.), crab grass ( Digitaria samguinalis L.) Scop, wild let- 
tuce ( Lactuca scariola L.), Solidago sp., blue grass (Poa prat ensis 
L.), Eragrostis megastachya (Koeiler) Link. The willow ( Salix alba 
var. caerules ( Sm ) Koch) is the first tree to come in. In a large num- 
ber of instances, these trees are killed showing that they are present to 
as great an extent as is allowed by external factors. 
The next belt (belt 4) will include a territory extending from Lake 
Michigan beginning with 83d St. and reaching westward to Marquette 
Ave. Thus Russel Square and Bessemer Park are included in this 
tract. This belt does not show marked difference as to annuals, but 
such perennials, as trees, add a few characters that were not present in 
the former zone. The willow becomes a conspicuous representative, 
not partially killed but in a good thriving condition. In addition, the 
cottonwood ( Populus deltoides) (Marsh) forms another representa- 
tive of this region, followed by the elm ( TJlm.us Americana L.), the ash 
{Fraximus americana L.), and sycamore ( Plat anus O ccident alis L.) 
The trees named after the cottonwood were characterized by a foliage 
that was very scant. Many show a spotting of the few leaves that are 
present, as well as curling. These conditions serve the purpose of cut- 
ting down the leaf area. The annuals found in belt (4) have much 
more foliage and furthermore will have better tone and quality, if 
such a thing can be said of a weed. In addition the following species 
will be noted: reed grass ( Phragmites communis Trin) Bidens , In- 
dian rice ( Zizania paiustris L.), Steironema quadriflorum (Sims) 
Hitch), loosestrife, ( Lythrum alalum Push), Gerardia paupercula 
(Gray) Britton. 
The willow is the outstanding tree. At Calumet Park this tree is 
the most common and is in a vigorous condition. The cottonwoods 
are next in line. As shrubbery in such a locality as is being studied, 
is in the majority of cases planted in a park and as trees serve as a 
protective agent by obstructing the action of smoke and gases, the ef- 
