Langc : REVEGETATIOX OF TRESTLE ISLAND. 



629 



lanceolata. It has occupied nearly one third of the section 

 and next summer, I think, the thistle will keep the cows off the 

 grass, and as the West section is a willow island, the East sec- 

 tion will be a thistle island. 



During September, 1900, there was over 5 inches of rain and 

 now water once more surrounds the East section and the cows 

 have not been there since about October ist. 



The West Section in the Season of 1900. The lake has risen 

 about two feet since September i5th this year and the south 

 half of the section is under water. Fire and cattle have thus 

 far never invaded this section. The willows are thriving. There 

 are probably five species of them, but Salix amygdaloidcs 

 forms the thicket. There are a few thrifty cottonwoods, and 

 aspens, one balsam poplar, and one slippery elm, Ulmus fulva. 

 Although sumac, hazel, box-elder, silver maple, wild haw, 

 flowering dogwood and three species of oak grow within half 

 a mile and most of them within a stone's throw of the island, 

 not one individual of all these has been found on either section 

 of Trestle island. 



Last spring several of the willow species, when they were 

 only about 24 months old, bloomed 'for the first time and pro- 

 duced fruit. A count on May nth revealed 38 staminate indi- 

 viduals and 27 pistillate individuals of Salix amygdaloides in 

 flower. The count was then made to include older trees of 

 the same species along the cycle path near the island and of a 

 total of 135 trees counted 74 bore male and 61 bore female 

 flowers. Although a number of the trees were measured last 

 year, only a few recent measurements of October 12, 1900, 

 can be given here. 



There are many willows on this section of the size of those 

 measured, while the two cottonwoods and the aspen measured 

 are the largest that could be found and the elm is the only indi- 

 vidual present. The average size of the large vigorous Salix 



