46 



MINNESOTA STATE HORTICULTURAL SOCIETY. 



from oue-third to one-half the weight of water it would contain if 

 saturated. In this case, it was found that soil when satvirated would 

 hold fifty-five per cent, of water and, as the mulched contained about 

 twenty-four per cent., it was in excellent condition for root action, 

 even in a period of severe drouth. 



Use of mulch on a gravelly knoll. At the Experiment Station is 

 a vineyard partly located on a very dry, open gravelly knoll. The 

 vines on this part suffered severely about five years ago from 

 drouth. The following season, they were heavily mulched with 

 stable litter and trash of various sorts, such as is common about 

 most farms, and it has been kept mulched since that time. This 

 mulch had rotted a good deal and, consequently, added considerable 

 organic matter to the soil. As the result of this treatment, the vines 

 recovered and have since yielded good crops of fruit, and even in 

 the past verj'^ dry season gave a" bountiful harvest, not being ser- 

 iously affected by the dry weather. On Julj^ 25, tests were made for 

 moisture in the soil under the mulch in the dryer part of this vine- 

 yard and, as a result, the top-soil was found to contain 18.3 per cent, 

 of moisture and the subsoil twenty-one per cent. There was no land 

 close b}^ with which to compare this, but on the same date the soil 

 in an oat field at the station, which was apparently and, without 

 doubt, much better adapted to holding water than that in the vine- 

 yard, contained 3.8 per cent, of moisture, an amount so small that 

 the plants would be powerless to take up any water from it. This 

 would indicate an increase of 14.5 per cent, of water, which is equiv- 

 alent to eleven barrels in the upper foot of each square rod, or 1,760 

 barrels per acre, due to the use of mulch on the soil, and this con- 

 clusion seemed to be born out by the appearance of the vines. It is 

 my opinion that without the mulch the fruit would have entirely 

 dropped from the vines in the vine5^ard. On August 4th, the top- 

 soil in the vineyard contained 10.3 per cent, and the subsoil 17.5 per 

 cent, of water, thus showing that, while it had lost some water, it 

 still contained a sufficient amount to enable the roots to work sat- 

 isfactorily. 



Mulched blackberries on the north slope. In the following 

 table is shown the amount of moisture contained under a very 

 heavy mulch on several dates dviring the most severe portions of 

 the drouth of the past summer. The land where these observations 

 were made is on the north slope of a hill. The east end of it is a 

 little heavy, while the west end is rather loose and gravelly. The 

 land was used for growing blackberries, and the mulch consisted of 

 six inches of old hay put on in the spring. 



Table showing water in soil under a heavy mulch on north slope: 



DAT£. 



Top- 

 Sub 

 Top 

 Sub 

 Top 

 Sub 

 Top 

 Sub 

 Top 

 Sub 



soil 



