THE PASSING OF THE TREES 185 



Study 24. Observations on the Decay of Fallen Trees 



Any natiiral 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 (wliite oak, linden, etc.). 

 Inhabits I ^^^^ ^^ ^^^^ (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 foimd in the logs, with 

 notes on their situation, occurrence, etc. 



