-7- 



2, Occasionally suckers are present or arise later from the area below the 

 wounds. Some of these suckers that extend above the wounded surface may be used 

 as "inlay scions" at the top end« 



3. Trees leaf out and often fruit the first season after the bark and cambium 

 layer are destroyed aromid the tree trunkl Horrever, the vigor of these completely 

 girdled trees vary considerably. On some trees the foliage and fruit appear normal j 

 foliage may be light in color but fruit size normalj and on other girdled trees 



the foliage may be light in color and sparse and the fruit small. 



The reason why completely girdled trees leaf out and often fruit the first 

 season after the bark and cambium layer are destroyed around the tree trunk is 

 because water and other materials which are taken up by the roots from the soil 

 pass up to the leaves through the vrood. In the leaves the water and the carbon 

 dioxide taken from the air by the leaves are united chemically, through the action 

 of sunlight, into glucose sugar. This sugar is the starting point for the synthe- 

 sis of all other carbohydrates and in turn for proteins, oils, waxes, and other 

 organic compounds which make up the bulk of the apple tree. After the manufacture 

 of the plant foods by the leaves, they move to other parts of the tree through the 

 phloem which is found in the baric. From the facts presented, it can be seen that 

 complete girdling will not deprive the top of the tree of v^ater and other materials 

 necessary for the manufacture of plant foods and that these materials v;ill be trans- 

 ported to all plant parts above the injured area. 



Reserve food stored in the roots enable the roots to function for some time, 

 often a year or two, thus keeping the top of the tree alive. However, a completely 

 girdled tree , unless repaired , will eventually'' die from starvation of the roots 

 for carbohydrates i 



— ^. J. Lord 

 //////////////// 



FTOGIGIDE COmiMTIONS 



The accompanying table indicates some of the advantages gained from mixing 

 fungicides in half and half strengths. T^relve categories are considered. Com- 

 bining two fungicides can contribute to more general control of diseases and to 

 better control of apple scab. The softening action of one on the other, each 

 at half strength, would improve safety and tolerance vathout losing any of the 

 virtues of either material at full strength. Improved wetting, nutrition, 

 back action, protectant action against scab and economy may be combined in one 

 spray by selecting two compatible materials each at half strength. 



The gains apply to the earl;y sprays and in the primary scab infection period 

 up to mid- June, Thereafter, the single fungicides are used at reduced strength 

 and preference is given to the materials leaving the least objectionable deposit, 

 having the greatest residue tolerance and leaving the fruit in the best natural 

 finish. 



E. F. Guba 



