60 BULLETIN 196, U. S. DEPARTMENT OF AGEICULTURE. 



Peas (Pisum sativum). 



The transition from the custom of growing a small patch of peas in the garden to 

 supply a few meals of a choice vegetable during the growing season to that of growing 

 hundreds of acres to supply a canning factory packing an article available at all 

 seasons is but an incident in the development of a great industry. The garden bed 

 was spaded, raked, and planted by hand. Brush was obtained from the orchard or 

 wood lot, and the rows "stuck" in order to insure the vines proper support. 'When 

 the green peas were picked and carefully prepared, they made what was at one time 

 styled a dainty dish. The fields are now cultivated, sowed, and the crop harvested 

 by machinery the same as any farm crop. There are several factories which take the 

 entire yield from more than 1,000 acres. The plants selected have sufficient rigidity, 

 no added support being necessary. The whole plant is hauled to the factory while 

 fresh and green, the same as a load of hay. 



The canning of peas dates back to the beginning of canning. Peas are one of the 

 three large crops packed. In this country the packing of peas is confined largely to 

 those States having a cool spring and plentiful rainfall. The southern limit of suc- 

 cessful growing seems to be from Maryland west to Indiana and northwest to Minne- 

 sota. Some peas are also grown on the highlands in Colorado and a few on the western 

 coast. Wisconsin, Michigan, New York, and Indiana lead in this crop. 



The pea used for canning belongs to the garden variety, Pisum sativum, of which 

 there are two general classes, the early, or round smooth pea, and the wrinkled pea. 

 The latter is much the sweeter. The Little Gem and Alaska are typical of the first 

 class, and Horseford's Market Garden, Admiral, and Advancers of the second. 



The peas are generally sown upon good ground, well prepared, as early in the 

 spring as frost will permit, and no subsequent cultivation given (except in California). 

 Instead of all being sown at one time, the seeding is made to extend over several 

 weeks, in order to prevent too many maturing at one time. When the peas are well 

 grown and ai'e still very tender, they are cut by mowing machines or special pea 

 harvesters, and are then loaded upon wagons and hauled to the factory. Until a few 

 years ago, the pods were picked fi'om the vines in the field and taken to the factory 

 in baskets or bags. This necessitated a very large force of men, women, and children 

 in harvesting, and added much to the cost of the product. There are only a few facto- 

 ries in the United States which follow this method at the present time, and it is limited 

 to a part of the pack. 



The vining machine, which is used for separating the peas from the pods while 

 they are still on the vine, is a very simple and ingenious device to accomplish a diffi- 

 cult task — the shelling of the tender pea so carefully that it will not be injured. It 

 consists of a large cylinder, perforated with many holes, which are large enough to 

 permit the peas to pass through, but not the vine. Within the cylinder is a heavy 

 shaft, bearing strong paddles or beaters. The cylinder is made to revolve rather 

 slowly and the beaters very rapidly, in the opposite direction. The vines are fed in at 

 one end of the cylinder, are carried upward by its motion, and fall upon the beaters, 

 which strike the pods, causing them to burst open and discharge the peas. The peas roll 

 out through the holes in the cylinder, and the vines pass out the opposite end. The 

 present vining machine is a modification of the podding machine which was invented 

 by Madam Faure. It was the first important step in the development of the pea- 

 canning industry. 



The next step in the process is that of cleaning, which consists of two operations; 

 first, passing the peas through a fanning mill to remove pieces of pods, leaves, and 

 dirt, and, second, washing, which is done in wire cylinders known as squirrel cages. 

 These cylinders are set on a slight incline and made to revolve slowly, so that peas 

 which enter at one end gradually roll out at the opposite end, and while doing so they 

 are well sprayed with pure cold water. After the washing, the peas are graded for 

 size. This is done by passing them over vibrating screens, which have holes of a 



