352 STATE BOARD OF AGRICULTURE. 



that Hopperburn, if not identical to, at least resembles Tipburn very closely, 

 led to the presumption that bordeaux mixture might be a factor in the con- 

 trol of that trouble also. The potato plats at the Station were sprayed 

 weekly with 5-5-50 bordeaux mixture, five applications being made during 

 the growing season. The sprayed and unsprayed plots were kept under 

 careful observation throughout the season and at no time were leaf hoppers 

 as numerous in the sprayed as in the unsprayed plots. On September 5th 

 hill counts made for Hopperburn showed 1.71 percent in the sprayed versus 

 27.75 percent in the unsprayed plats. Bordeaux mixture was instrumental 

 therefore in the control of Hopperburn. The spray does not kill the leaf 

 hopper but merely acts as a repellant. Vines covered with bordeaux mixture 

 are not relished by the insect and it flies away to other hosts or other potato 

 fields which are not sprayed. For best results the first apphcation of bor- 

 deaux should be when the vines are 5 or 6 inches tall, followed by a second 

 sprajdng about a week later. At least two subsequent applications should 

 be made at intervals of 10 to 14 days. Getting the vines covered with bor- 

 deaux mixture early will ward off the overwintering adults and at the same 

 time insure freedom from the ravages of the first generation nymphs. The 

 subsequent sprayings will repell the adults of the first generation which come 

 back about a month later to lay eggs for the second generation. This re- 

 sults in the losses from Hopperburn being reduced to a minimum. 



MISCELLANEOUS PROJECTS. 



There are many problems connected with the developing of a ' 'new agri- 

 cultural territory,' ' such as the Upper Peninsula, that may or may not be of 

 general interest, yet demand attention for those who are interested. Land 

 clearing, muck soil management, sandy soil management, and other similar 

 problems are among those here reported to which the Station is giving at- 

 tention. 



Manj^ of these projects are co-operative where two or more interested parties 

 or organizations are assisting the Station in the sohdng of the problems to 

 the common good of all. 



Fig. No. 23. County cooperative barley and oat test, Delta County 1920. 



