26 The Bulletin 



3. Tillage may aiigmeut chemical activities. 



/. By aiding in setting free plant food. 



g. By promoting nitrification. 



h. By hastening the decomposition of organic matter. 



4. Tillage indirectly protects the fruit plantation : 



i. By destroying weeds. 



;. By destroying insects and breaking up their breeding places. 

 Generally, the peach orchard should be given clean culture all the 

 early part of the growing season throughout its lifetime, beginning in 

 the spring of the first year after the trees are set. 



In normal seasons the orchard should be plowed in the spring just 

 as soon as the ground is in suitable condition to work properly. The 

 date of starting the tillage will be influenced, no doubt, by the charac- 

 ter and condition of the cover crop. The handling of the cover crops 

 will be discussed at another place. 



Some growers during the first two seasons confine the tillage to strips 

 along each side of the rows of trees, enlarging the strips so that by 

 the third season the entire surface will be tilled. 



The ground should first be plowed with a turn plow, throwing the 

 soil towards the trees one year, and aAvay the next. The plowing should 

 be done shallow, not over 3 or 4 inches. By plowing relatively deep, 

 say 5 to 6 inches, when the trees are very young, deeper plowing can 

 be done when the trees are older without so much danger to the roots. 

 Extreme care should be exercised so as not to injure the roots or the 

 trees with tillage implements. The ploAv may be used closer to young 

 than to old trees, as their roots are slightly deeper in the ground. In 

 any case the space next to the trees should be plowed with an orchard 

 harrow to prevent injury to the roots. 



Various modifications of the harness are in use to prevent injury to 

 the trees. Several forms of traceless harness have been designed to 

 enable a span of horses to be driven quite close to the trees without 

 injury. 



The character of the soil will in a large measure determine the tillage 

 implement. If the soil is light, sandy, and not much compacted, it 

 may not be necessary to plow; but some type of cultivator or disk will 

 serve to pulverize the surface soil to such a depth as to form a mulch 

 3 to 4 inches deep. After plowing, if the surface is rough, it will be 

 found advisable to follow with a disk and thou to harroAV to make a 

 mulch and to level the surface. 



In the western part of the State where many poach orchard soils are 

 sometimes so rocky iliat the disk harroAV cannot be used, the spring- 

 tooth harrow gives the best results. Where trees are large, a tillage 

 implement of the extension type is more useful for stirring the soil 

 near the trees. 



After the initial plowing in the spring, subsequent cultivations are 

 mainly to preserve a dust mnlch 3 to 4 inches deep to prevent excessive 



