498 IOWA DEPARTMENT OF AGRICULTURE. 



an old lake of water in former times, and where the water level varies from 

 twenty to twenty-five feet below the surface of the ground. This orchard has 

 been very healthy and productive, and last fall it produced more than two 

 thousand bushels of first-class apples, while across a slough not more than 

 fifty rods from it in my old orchard, many Wealthy trees were killed by sun- 

 scald, because they failed to ripen at the proper time after protracted sum- 

 mer droughts. 



I have lost many Wild Goose plum trees on account of sun-scald after 

 they have failed to ripen at the proper time in the fall, but I have been very 

 successful in growing them when they were grafted on« the limbs of the 

 Black Hawk plum. In 1866 I had twelve acres of hazel bushes on the north 

 side of my farm adjoining a large body of tall timber, and all over the hazel 

 thicket there was a good stand of young burr oak and jack oak trees from 

 ten to fifteen feet high. But in 1871 I fenced the hazel thicket and about 

 twenty acres adjoining it for a cattle pasture. About 1884 nearly all of the 

 hazel bushes had been destroyed by the cattle, and until 1888 I had never 

 seen trees grow faster than the oaks in my hazel thicket; but in 1890 they 

 made but little growth and afterwards they died faster than I could use them 

 for fuel, fence posts and other purposes until now, when there are only a few 

 of them left. As young oaks stood in other hazel thickets, which had not 

 been disturbed by cattle, and continued to grow rapidly, the cause of my 

 trees dying was not hard to explain. When the hazel bushes were destroyed 

 the ground was covered very soon with a good stand of blue grass, and as 

 it was closely cropped by from thirty to forty head of cattle, it was not long 

 until the humus in the surface soil was very scarce and the ground did not 

 contain enough of water to supply the wants of the oak trees, and they failed 

 to ripen before cold weather. 



There is not only a great scarcit}'' of humus and water in the soils of many 

 Iowa orchards frequently, but the same trouble extends to thousands of 

 farms in- Iowa where no attempts have been made to plant orchards. From 

 1855 until 1875 farm crops were much better in Iowa than during the last 

 thirty years. During the former period of time from twenty to twenty-five 

 bushels of spring wheat per acre was the rule; while during the latter. period 

 the crops became poorer, until ten bushels or less per acre were as much as 

 the best farmers expected and they quit growing spring wheat. But the de- 

 cline in the yields of oats, timothy and many other kinds of crops was nearly 

 as great as in wheat. If we should say that such poor crops were caused by 

 a decrease of the rainfall since 1875, the statement would not be true, as the 

 weather records at McGregor and Muscatine show .that the average annual 

 rainfall (including rain and snow) in the northern half of Iowa during the 

 last fifty years has been about thirty-four inches. We find that the average 

 annual rainfalls in Iowa have differed very much, but that during the peri- 

 ods of five or ten years they, have differed but little. The seven wettest years 

 at McGregor between 1850 and 1890 were as follows, viz: 1858, 1860, 1876, 

 1878, 1881, 1883 and 1890. The average for the seven years was forty-two 

 inches per year. The seven driest years were 1863. 1864, 1868, 1870, 1872, 

 1886 and 1889. The average for the seven driest years was twenty-four 

 inches per year. There was a difference of eighteen inches between the 

 averages of the seven wettest and the seven driest years. 



