-iO BrLLETix OF Wisconsin Natural History Society. Vol. 1, No. 1. 
The only place where I have found 6^. inyrtilloides is in the 
same ravine at Fox Point where the balsam poplar grows. Wheel- 
er mentions it as occurring in Larkins' tamarack sw^amp. 
A word should be said of the relative frequency of shrubby 
and tree-like forms of willows. The only species which in this 
region ever assume the tree form are S. nigra and aiiiygdaloidcs. 
Except in the swamps, of which we have spoken, the tendency of 
these species seems to be to become trees in all cases ; where we 
find them as shrubs, we may be reasonably sure that they are quite 
young. The largest willows I know of in the region (aside from 
S. alba in cultivation) are in a group of three on the road to Elm 
Grove, about half way between the County Poor Farm and the 
Waukesha line. The largest of these has an estimated height of 
sixty feet, the others are slightly lower. Their breast-high diam- 
eters are 23, 25 and 29 inches^ respectively. Their trunks seem 
to be sound, and they are remarkable for the fact that they have 
no branches until a considerable height above the ground. Most 
willows divide almost immediately above the ground, if they do 
not come out of the root in divided shoots. Trees of a size ap- 
proximating these three are very rare in this vicinity. 
As to the relative numbers of the various species, .S'. ainygda- 
loides is by far the most common ; next come 6^. nigra and flnvi- 
atilis; the others are comparatively infrequent, although in the 
localities where they occur at all, they are not usually solitary. 
General Remarks on Distribution* 
In the map illustrating the distribution of plants in Eastern 
Wisconsin (7) a narrow strip of what is there called the Hard- 
wood and Conifer Group, stretches southward along Lake Michi- 
gan to the vicinity of Port Washington. This group is charac- 
terized by the presence among the hardwood forests of the pines, 
hemlocks and other conifers native to this state, in more or less 
great numbers. The group is one with essentially northern char- 
acter, as compared to the Maple and Maple and Beech Groups, 
lying to the southwest of it, and the regions still further south- 
west where the oaks predominate. 
Now the fact is remarkable that quite a number of northern 
trees are found in limited localities in the region under discussion, 
such as one would be more apt to look for in the Hardwood and 
Conifer Group. The vellow birch has already been mentioned, 
so has the balsam poplar and the white birch. To these should 
be added the white pine, which at the time of the first settlement 
7. Atlas of Wisconsin Geological Survey. 
