18 
generally found on the old pruned branches, it is necessary to 
exercise unusual care in pruning and treating the cut surfaces. 
This same fungus was obtained from other plants. In 1916 it 
was found on an English haw. This particular tree had branched 
close to the ground and consisted of two main stems each about 
five inches in diameter at the base and about twelve to fifteen 
feet high. One of these branches was entirely dead, the wood 
was badly decayed and the surface was well covered with the 
brackets of the fungus, the latter extending from the ground to 
practically the tip of the branch. The Park workmen removed 
this branch but in 1917 new fruiting bodies of Polystictus verst- 
color developed at the base of the other branch. 
Very typical specimens of Polystictus hirsutulus Schw. were 
collected on an English oak. These were located on one of the 
larger branches and were associated with extensive decay of the 
wood. 
The fruiting structures of other higher fungi were collected. 
An unidentified polypore was taken from several large wild cherry 
trees. Schizophyllum alneum Schr. was collected on dead 
branches of Ailanthus in the Botanic Garden and on sumac in the 
Park. Pleurotus ostreatus Jacq. was collected on the sugar 
maple. A species of Stereum was secured from the English oak 
and the black birch 
In connection with the more intensive survey of the condition 
of the trees in a limited section of the Park, it was observed that 
a large number of the decayed areas were associated with previous 
pruning operations. Extensive decayed places were found on 
225 trees where limbs had been removed. Of these 157 were 
classed as major decays and 68 as minor. It has also been noted 
above that the fruiting structures of the decay-producing or- 
ganisms were frequently found adjacent to pruned surfaces. 
Obviously, since wood-destroying fungi are essentially wound- 
parasites, it is particularly important to prevent their entrance at 
the places where limbs are removed. 
As noted in the previous report the most serious disease en- 
countered was one affecting the gray and white birches in both 
the Park and the Botanic Garden. The trouble was much more 
apparent in the Garden on account of the large number of the 
