THE PASSING OP 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.). 



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 . A list of the carnivorous insects found in the logs, with 

 notes on their situation, occurrence, etc. 



Inhabits 



