174 
THIRTEENTH REPORT. 
or birds are by far the most numerous in species. For example, the 
willows, poplars, Epilobiums, and many species of the Oompositae are 
well represented. All of these species are scattered far and wide by 
their wind borne seeds or fruits. Plants producing berries and pulpy 
fruits, like the dogwoods, hackberry, strawberry, huckleberry, cranberry, 
juneberry and wild cherries, were probably introduced through the agency 
of birds. Many of those whose seeds or fruits are not so easily transported 
are poorly represented on the islands or entirely absent; for example 
only one beech and one jack pine, both common on the mainland, were 
found. The hickories and the hazelnut are absent. 
The occurrence of two species is not easily explained. The tree known 
as the hackberry or sugarberry is common on Little Charity, one tree 
being fourteen inches in diameter and fifty feet in height. The fruit of 
this species is sweet and pulpy and eaten by birds, but, while it has 
reached Little Charity Island, not a single specimen was found on Char- 
ity Island although the latter is many times larger than Little Charity 
and situated about the same distance from the mainland. The tree has 
not been found by the writer on the adjacent mainland, but it is re- 
ported by W. H. Wallace as occasionally found near Bayport, Huron 
County. Apios tuberosa Moench, often called the wild bean or ground 
nut, is another puzzling case. This plant is a beautiful vine that twines 
and climbs over bushes. It bears numerous chocolate-colored or brown 
purple flowers in dense short racemes, but in the course of thirty years 
of observation in eastern Michigan it has never been seen to bear fruit, 
spreading instead by means of.tuberous enlargements of the rootstocks. 
It bears fruit abundantly in the south and has been reported to do so 
in Michigan, but it is believed that it only rarely fruits in this state and 
certainly not often within one hundred miles of Port Huron. It is com- 
mon on the mainland and frequent on Charity Island, and it is not clear 
how it could traverse the intervening seven miles of water. 
As a rule, sand binding plants are not very prominent, but on Little 
Charity Island the beach pea almost completely covers the sandy ground 
on the south side. On Charity Island the low juniper is fairly well es- 
tablished in the sand on the west side of the north end, and the sea sand- 
reed is abundant and holding down the sand on the shore near the light- 
house. The other characteristic shore plants are not abundant but are 
the same as on the mainland. The species noted are Pitcher’s thistle, 
Artemisia caudata, Calamovilfcv Ion gif alia, Agropyron dasystachyuin, 
and Juncus balticus littoralis. 
The usual weeds found on or near cultivated ground are few and on 
Charity Island confined mostly to the vicinity of the lighthouse and on 
Little Charity to the neighborhood of the fishing buildings. 
The distribution of trees and shrubs on Charity Island is much the 
same as on the mainland. Bed Oak is dominant on the sand ridges, es- 
pecially near the beach, and extends to the rich damp ground. Between 
the ridges and in rich ground on the east side of the north end, white 
elm. white ash, ironwood, red maple and basswood are frequent. The 
white pine trees that occur here are not generally very large or prom- 
inent but fine trees of red pine are found. 
The following list of plants found on the island contains 372 species 
(exclusive of the three unidentified thorns mentioned later). These 
species are all found on the mainland to the south but nearly 900 spe- 
