or when plants are wet with dew reduces mechanical shatter. Draper -type 

 windrowers can often be used advantageously to concentrate light growth 

 and speed up a harvest. It is usually necessary to narrow a conventional 

 swath to accommodate most combines. A grass board on each side of 

 the mower cutterbar works satisfactorily under some conditions, but the 

 use of a "Roto-Windrower" 1 narrows the swath without concentrating it 

 too much and causes less mechanical shatter. 



In the West, most grass and small legume seed crops have to be 

 mowed, windrowed, and combined from the windrow, if earlier than usual 

 harvest recommendations are followed. Direct combining during most 

 years without using a suction seed reclaimer, results in seed yields that 

 are about the same as those obtained by combining from the windrow at 

 the usual time. In areas where strong winds, rain, and low humidity menace 

 seed production, preharvest chemical spraying to cure the crop for direct 

 combining may be practical. 



Method -of -harvest studies in the West for crimson clover, subclover, 

 and similar crops were discontinued in 1959 because it appears that an- 

 swers have been found to enable growers to reduce their field shatter 

 losses. The answers for crimson clover are: (1) Harvest at the earlier 

 than usual time and obtain about 22 percent more seed than at the usual 

 time, or (2) combine the crop directly using a suction seed reclaimer as a 

 harvesting adjunct and obtain about 26 percent more seed than by normal 

 methods. For subclover: Harvest at the earlier than usual time and obtain 

 37 percent more seed, or directly combine, using a suction reclaimer, and 

 obtain 184 percent more seed. 



These good results from harvest time studies also have prompted 

 research attention aimed at developing more efficient mowing methods 

 for both subclover and crimson clover. The studies were urgently needed 

 because of high crop moisture usually encountered during earlier than 

 usual harvests and because crops at this stage of growth are green and 

 tough. Tested were rotary field choppers, different types of mowing bars, 

 and swath dividers. 



The choppers were equipped with vertical, rotating, flat cutters and 

 were adjusted to just touch the ground. Their use in subclover gave an 

 estimated 27.5 percent increase in yields. While this increase was not the 

 maximum attained, it show^s that increased yields are possible with the 

 proper type of equipment. 



The several types of mowing bars were tested in subclover because 

 subclover is probably the most difficult of any crop to mow when being 

 harvested for seed. It develops its seed near the surface of the groxind 

 and has to be mowed close to and sometimes under the surface of the 

 ground. Single sickle mowers plug up quickly when they dig into the ground 

 or cut dense subclover close. Earlier than usual harvests, when the crop 

 is green and tough, aggravate these difficulties. 



Of the mowing bars tested, a 7-foot, double-sickle (both moving) 

 bar with sickle blades spaced 3 inches apart and with a 1 1/2 -inch oscil- 

 lation was the only one that cut a 230-foot test swath without plugging and 



^This attachment, as used in tests in South Carolina, was patterned after a similar attachment developed and 

 tested at the Ontario Agricultural College, Canada. 



