-5- 



That only about IS^^o of the apple trees in the U.S. were of non- 

 bearing age in 1940, compared v;ith about 24fo in 1930? Even thouch there 

 were only about l/o as many apple trees in the United States in 1940 as 

 in 1910, the production has not declined greatly owing in part to the 

 gradual shift to better soils, higher yielding varieties, less caustic 

 fungicides, and better all around orchard management. 



That an average ton of farm laanure contains about 10 pounds of 

 nitrogen, 5 pounds of phosphoric acid, and 10 pounds of potash? The amount 

 of manure produced annually per 1000 pounds of live weight is about 15 

 tons by cov/s, 12 tons by horses, 10 tons by sheep or fattening cattle, 18 

 tons by hogs, and 4.2 tons by chickens. 



That the guano birds of Peru consume about 5g- million tons of fish 

 annually, while the people of Peru consur.ie only 4 thousand tons. The guano 

 birds are considered to be araong the most important in the world because 

 of the enormous quantities of fertilizer for which they are responsible. 



That ragv:eed has at least one advantage to offset its disadvantage 

 as a spreader of hay fever? The ragweed borer has been found to be host 

 to several parasites of the Oriental fruit moth, a serious pest of peaches. 

 One experiment station has even recommended that ragv/eed be allovred to grow 

 in peach orchards in order to favor the development of these parasites. 



That apple scab, fungus disease Enemy !Jo. 1 of apples, is known in 

 all apple growing regions from the Atlantic to the Pacific? It is also 

 found in British Columbia and in Southern Canada, in European countries, 

 and in Australia, New Zealand and South Africa. The annual loss attributed 

 to this disease in the northern part of the United States alone is estimated 

 at v3, 000, 000 while for the entire United States the loss is approximately 

 !1^40,000,000. 



That the entrance of apple scab into a leaf or fruit is dependent to 

 a large extent upon temperature? If the temperature is 43° the process takes 

 about 15 hours, at 48° 11 hours, 59° 7 hours, 68° 4 to 5 hours, 75° 6 hours. 

 Higher temperatures tend to retard or prevent grovrth. Leaves must remain 

 wet about three times as long at 43° as at 68°. 



That spray lime if exposed for a period of time to the air, loses 

 its effectiveness as a corrective for arsenical burning? This is due to the 

 fact that thfe essential ingredient, calcium oxide, is changed into the car- 

 bonate form, calcium carbonate, by the absorption of carbon dioxide from the 

 air. In the carbonate form, the calciura is ineffective in preventing spray 

 injury. 



That 29^^ of the farm accidents in the United States have to dowLth 

 machinery? 22^^ involve animals; lO^o, excessive heat; 9^^, falls of various 

 kinds, 9^j, vehicular traffic, 6% lightning, and 15Jo other causes. 



That about 18,500 farmers in the U.S. lost their lives last year be- 

 cause of accidents? In addition, it is estimated that 100 times as many 

 were injured. Hazards are even greater no\/ because of new help. Greater 

 care must therefore be exercised to avoid accidents, particularly with trac- 

 tors and other farm equipment. 



