8 MISSOURI AGR. EXP. STA. RESEARCH BULLETIN 41 



operation the results here attained could not have been secured. 

 The field work was done in the summer of 1918. All computa- 

 tions were completed during the year following. The manu- 

 script has been subject to revision particularly in the light of new 

 information of a general nature bearing on tree growth in the 

 Ozarks. 



Measurements. These were made in part on trees cut in the 

 usual course of the company's operations ; in part on trees cut by 

 the company in the particular interest of this work. The trees 

 measured were grouped into four species; white oak (Quercus 

 alba L.), post oak (Quercus minor (Marsh.) Sargent), black jack 

 oak (Quercus Marilandica Muenchh.) and black oak (Quercus 

 velutina Lam.) Black oak was extended to include the closely 

 related red oak, Texan oak and Spanish oak. 



Numerically these four oaks are represented in this study as 

 follows : 



Post Oak 118 trees 



Black Oak 114 trees 



Black Jack 54 trees 



White Oak , 49 trees 



Total 335 trees 



The bole of each of these trees was cut into four-foot lengths 

 and a complete stem analysis was made with ring counts and the 

 usual measurements at each section with the exception of those 

 sections showing defects. 



Computation. The procedure followed in computing vol- 

 umes and other derived values from the recorded data has been 

 described in the Journal of Forestry,* in connection with a dis- 

 cussion of the mechanical conveniences employed and reference 

 is here made to that article for a detailed statement of the methods 

 used. 



RESULTS 



Diameter Growth. Diameter growth was studied by finding 

 the relation between the radial growth during a given decade and 

 the radius at the beginning of that decade. This relation is shown 

 in Figure 1 although, for obvious reasons diameters are here 



*Pegg, Ernest C, Mechanical Aids in Stem Analysis, Journal of Forestry, XVII; pp. 682- 

 5: Oct. 1919. 



