MACHINERY 



1947 



soil, leaving more or less of a mulch to prevent evapora- 

 tion. Similar claims are made for corrugated and 

 tubular rollers. 



A so-called subsurface packer, consisting of a series 

 of wheels with wedge-shaped tread, is on the market, 

 for which many claims are made. 



2267. One form of roller pulverizer or packer. 



The Montana Experiment Station has been instruct- 

 ing the farmers of the state how to make their roller 

 pulverizers of concrete. A circular has been issued 

 describing and illustrating this method in detail. It is 

 stated in this circular that the roller should weigh not 

 less than 225 to 250 pounds to a foot of width. This is 

 provided the roller is not used on moist soil. The con- 

 crete roller described is about 19 inches in diameter. 



The planker (Fig. 2268) or clod-smasher is a home- 

 made wooden implement which is very useful for crush- 

 ing clods and for surface-smoothing. In fact, on some 

 Hawaiian soils the wooden planker has been successful 

 in pulverizing the top soil when both the disc- and Acme 

 harrows have failed. The planker is effective in listed 

 corn after the first plowing when the soil tends to be 

 cloddy. The weight of the planker may be gaged 



2268. The planker. 



according to the type of soil. The planker is more gen- 

 erally successful when the surface soil is rather dry. 

 When the soil is wet and sticky, it may cause more 

 harm than good by causing excessive packing of the 

 soil. This also applies more or less to the roller. 



Cultivators. 



The term cultivator is applied to a number of tillage 

 tools. These are surface tillage tools but are usually 

 equipped with shovels or discs instead of teeth and 

 some of them till the soil to a slightly greater depth 

 than the harrow. 



Cultivators are more generally used between the 

 rows of growing crops, corn in particular. Corn-stubble 

 is, however, frequently cultivated in the spring with a 

 corn-cultivator previous to listing the corn. The main 

 purpose of cultivators is to destroy weeds, pulverize 

 and ventilate the soil, and thereby conserve moisture 

 and plant-food. 



2269. Garden or truck cultivator. 



The cultivator has developed from the single-shovel 

 and double-shovel cultivator, which cultivated only 

 one side of a row, to the single straddle-row and double 

 straddle-row types. The single- and double-shovel types 

 have also developed into cultivators having from five 

 to fourteen shovels which are used for cultivating 

 between two rows. 

 These are used 

 almost exclusively 

 now for garden and 

 truck crops. Fig. 

 2269 illustrates a 

 common type of 

 garden cultivator. 

 These are made for 

 both horse- and 

 hand-power. 



Corn - cultivators 

 are of several types. 

 There are single- 

 row walking-culti- 

 vators with and 

 without tongues, 

 and single-row and 

 double-row cultivators. The tongueless or "speechless" 

 walking-cultivator is a rather old type and its use in 

 the corn-belt now is rather limited. When standing 

 still it was likely to fall in a heap if not held steady. 



The single-row four-shovel walking-cultivator with 

 a tongue (Fig. 2270) is a very effective corn-cultivator, 

 particularly for second plowing. However, a strong 

 man is required to operate a walking-cultivator, 

 especially during second plowing when considerable 

 care is required not to injure the corn and at the same 

 time to effect thorough cultivation and destroy weeds. 



Riding-cultivators are in very general use now for 

 corn-cultivation. Fig. 2271 illustrates a common type 

 of four-shovel single-row riding-cultivator. The shovel 

 gangs are hung on springs and the shovels themselves 

 are also sometimes fitted with springs better to with- 

 stand shock. The operator regulates the depth of the 

 shovels by hand levers, maintains the required depth, 

 and guides the gangs with his feet, the guiding being 

 frequently aided by a hand lever. 



Corn-cultivators now have four, six, eight, and some- 

 times ten shovels. While the four-shovel types do very 

 good work, the six-shovel types effect a rather more 



2270. Walking single-row four-shovel tongue cultivator. 



2271. Riding single-row four-shovel cultivator. 



