approximately V2 gram of poison. A special tool was used to create a pocket 

 between bark and wood of the tree so the tabs could be inserted. This tool 

 is a small bark peeling spud smilar to a bent screw-driver. Forcing the tool 

 straight into the tree through the bark, a vertical slit is started which readily 

 opens when it is pried back with the spud. Then the spud is slid between 

 wood and bark for about two inches. One of the tabs is applied at the edge 

 of the slit, the spud is withdrawn, and the tab forced into the bark pocket. 

 Over 500 trees have been treated in this manner and results show that pine 

 trees up to four or five inches in diameter and from 15 to 30 feet high may 

 be killed with only one tab. However, if the top is limby and there are many 

 heavy branches, it is much safer to insert one or two more tabs since the 

 time involved is only a matter of a few seconds. 



Hardwood trees may be killed by using the same method. However, 

 because of the irregular branching habits of hardwoods with the tendency 

 to form spreading crowns, it is necessary to use more insertions per tree than 

 is the case with pine. Another difference between hardwood and softwood 

 trees is that the soft woods can be treated throughout the year, while the 

 bark on hardwoods becomes so tight that it is not possible to make satis- 

 factory bark pockets except during the normal peeling season (roughly 

 from late May to early August). 



Trees treated in this manner usually show wilted foilage in a few days 

 and dead crowns within a month. 



L. C. Swain 



OTHER ACTIVE PROJECTS 



Utilization of Low Grade Wood. L. C. Swain 



Possibilities of Propagating High Sugar-Producing Types of Sugar Maples. 



C. L. Stevens, S. Dunn 



The Characteristics of Sap Flow. C. L. Stevens 



Reproduction Studies. C. L. Stevens 



A Study of White Pine Stands. H. B. Kriebel 



Inheritance of Insect Resistance in Eastern White Pine H. B. Kriebel 



Fruits 



(See Horticulture) 



Horticulture 



Varieties of Tree Fruits That Hold the Spotlight. 



The following varieties of winter apples yielded well at the Horti- 

 cultural Farm and were held in good saleable condition in common cold 

 storage until May. Idared, Redwell, and Fireside are red or red-striped 

 varieties of good quality and appearance that should be planted on a limited 

 scale for further testing elsewhere in the state. Crescent has been our high- 

 est quality yellow plum and is very hardy. Redcoat plum has developed ex- 



29 



