EXPERIMENT STATION REPORTS. 109 



When trees are mulched, care should be taken to protect them from 

 mice which sometimes girdle large, bearing trees, and are very destruc- 

 tive to young trees. It is not only advisable to keep the mulch a foot 

 or two away from the trunks, about which a mound of earth should 

 be placed, but the trunks themselves should be wrapped with wooden 

 veneers, building paper or similar materials. 



Cultural experiments are being carried on in a number of orchards. 

 Arrangements have been made to divide the trees into four to six plots, 

 each of which is treated in a different way. The object of these experi- 

 ments is to ascertain just which method will be found best for the soil 

 and climate where the orchards are located. The growth of the trees, 

 the quantity, flavor, color and shipping quality of the fruit will be 

 noted. 



Although it will be several years before final results can be reached, 

 the experiments have gone far enough to show that under ordinary 

 conditions the best results cannot be obtained in a sod orchard unless 

 a sufficient amount of mulching material is provided to prevent the 

 growth of grass under the trees. 



The Prevention of Black Rot of the Grape. — Although this disease 

 has been very troublesome in most of the states farther south it has 

 done comparatively little harm in Michigan. For the most part the 

 Michigan vineyards are upon elevated, rolling locations where the soil 

 is of a sandy nature. The weather also during July and August is 

 generally hot and dry, all of which conditions are unfavorable for the 

 development of the fungus that causes black rot. During the last two 

 years, however, the rain fall during the summer has been unusually 

 heavy and there has been a considerable amount of hot, muggy weather. 

 In 1905, the black rot appeared in several vineyards in the vicinity of 

 Lawton and Paw Paw and reduced the crop to a noticeable extent. It 

 is more than probable that, if the present season resembles that of last 

 year, the vineyards in which the disease has appeared will suffer very 

 seriously and it will most likely spread to others in the vicinity. 



It has been known for nearly twenty years that if Bordeaux mixture 

 is used in the vineyards the loss from black rot will be largely, if not 

 entirely prevented. Several persons whose vineyards were attacked 

 last year have obtained power spraying outfits and have already made 

 two or three applications. Two of these parties have undertaken 

 systematic experimental work in co-operation with the department to 

 ascertain just when the spraying should be done to secure the best re- 

 sults and the number of app>lications that will be necessary. 



The Potato Blight and Rot. — In a general way what has been said 

 regarding the black rot of the grape applies to the blight of the potato. 

 This disease seldom fails to do much harm to the potato crop in the 

 eastern states but for the reasons given for the comparative freedom 

 from rot in the Michigan vineyards it has only been during the last 

 two or three years, when the summers have been unusually wet and 

 muggy, that it has done noticeable harm in Michigan. This disease 

 also yields readily to spraying with Bordeaux mixture and several par- 

 ties are carrying on experiments to ascertain just how many applica- 

 tions may be made with profit, and the best time for spraying. 



Numerous other experiments are being carried on in a co-operative 



