THE PASSING OF THE TREES 185 
Study 24. Observations on the Decay of Fallen Trees 
Any natural woods, having a variety of fallen trees, or even 
of old stumps, will do for this study. The individual equip- 
ment needed will be sharp brick hammers or hatchets for 
stripping bark and digging into logs, and vials of alcohol to 
hold insects, pending their identification. A few axes will be 
needed for common use. 
The program of work will consist of taking some logs (or 
tree-stumps) to pieces, observing their condition and rate of 
decay in various parts, and collecting specimens of their 
inhabitants. 
The record of the work may consist of: 
1. Notes on the phenomena of decay in logs of several 
species: changes in color and hardness; relative rate of 
progress in bark, sapwood, heartwood, knots, etc.; plants 
growing in the residual heaps, etc. 
2. A table of the wood-inhabiting insects found, prepared 
with column headings as follows: 
Name of insect (ask instructor, if you do not know it). 
Stage found (larva, pupa or adult). 
Kind of tree (white oak, linden, etc.). 
Inhabits Part of wood (bark, sapwood, heartwood, etc.). 
Condition (sound, red-rotten, white-rotten, 
etc.). 
Burrow (depth, form, direction, etc.). 
Products (chips, borings, dust, etc.). 
Occurrence (rare, common, abundant, etc.). 
Remarks. 
3. Alist of the carnivorous insects found in the logs, with 
notes on their situation, occurrence, etc. 
