- 7 - 



Specifications cf paraff inic-type "raw" oils preferred for manufacturing oil 

 emulsions and miscible oils for use on fruit trees in Green-Tip to Delayed- Dormant, 



Good Quality, Better Quality 



Low Cost, Safe Higher Cost, Safer 



Viscosity (Saybolt, at lOOop,) 90 



Gravity (A.P.I» degrees) 28 (minimum) 



Unsulfonated residue (A.S.T.M.) 75 " 



120 seconds -- 

 31 (minimum) 

 90 " 



Homogeneity 



A relatively narrow boiling 

 distillate portion of petroleum. 



* The following methods of testing oils are to be used: Viscosity: 

 Kinematic, A.S.T.M. Designation: D445-39T. Conversion to Saybolt 

 Universal Viscosity, A.S.T.iil. Designation: D446-39, A.P.I. Gravity: 

 A.S.T.M. Designation: D287-39, Unsulfonated Residue: A.S.T.M, 

 Designation; D483-40. 



— Ellsworth H. Vilieeler 



********** **:*********)(<***J(<Jt: ****** ****** 



MANAGING SIVlALL F0R5STS 



(This article is included in FRUIT NOTES not because some orchards resemble 

 a forest, but because forest trees are included in many of our fruit farms.) 



Harvesting the timber crop is a very important part of a management program. 

 Harvest cuttings are made principally to obtain cash from the mature trees rather 

 than improve the remaining trees. The manner in which this operation is performed 

 decides whether the forest will be completely destroyed or left in shape to pro- 

 duce another crop in 5 or 10 years. There are several methods of harvesting the 

 crop, namely clear cutting, leaving seed trees, cutting to a diameter limit, and 

 last, selective cutting or selective logging. 



There are some points in favor of the first three methods mentioned, but the 

 best method is selective logging, or selective cutting. It is the best way to 

 harvest a small forest of mixed age. In the small forest the farmer looks over 

 each tree to decide w'hether he should cut it now or allow it to grow. This 

 method combines both stand improvement and harvest cutting. In this selective 

 cutting, there are such trees as those that are diseased or insect infested, the 

 limby, crooked, or scarred trees, the old ones and less desirable varieties are 

 cut which benefit the remainder. The other trees that are cut are those that 

 have passed the best growing period or can be sold more profitably now than in the 

 future. And so it is recommended that trees of low quality or over mature be cut 

 for sale right now. Another advantage of selective logging is that each tree can 

 be harvested at its highest value. 



Too often trees are cut just when they arc making their most rapid grovith. 

 Sometimes this may be justified by high market prices or by the cnmer's need for 

 cash. Frequently however, he takes a real loss by cutting too soon. It is 

 possible for the owner to find out exactly how fast trees are growing by using the 

 following formula: P _ 400 P _ Percentage of grovrt;h in last year 



ND 

 N -; Number of rings in the last inch 



D _ Diameter of tree 



