The problem now is to make use of these large sets, and not allow them to go to waste. It has been shown that these clams when transplanted will grow much faster, and will not perish; therefore, clam farming offers both the possibility of saving these natural sets and utilizing barren ground.
Methods of spat collecting have been constantly referred to in connection with clam farming, especially by the Rhode Island Fish Commission, and the impression has been given that clam farming can never become a success until some practical method of spat collecting has been found. With the soft clam there is no need of any method of spat collecting, as the natural set is more than sufficient for restocking the barren flats. All that is necessary is to utilize the enormous natural sets. If this is done, the barren flats of Massachusetts can be made productive.
The main difficulty is in devising some method of obtaining the small clams with sufficient rapidity. As the nature of the soil and the size of the clams vary, no one method can apply to every case, and it depends upon the ingenuity of the clammer. The methods used at present are: (1) digging with an ordinary clam hoe, which is slow work; (2) digging in shallow water, so that the clams may be washed out; (3) digging a series of trenches across the heavy set area, and scooping out the clams washed in these trenches; (4) carrying both sand and clams by the dory load; (5) by using a sieve, in the form of a cradle, which washes the clams out in the water. This last method is the most successful for small clams, and has been used by the commission in obtaining seed clams for their experimental beds. By using a cradle 3 by 2 feet, covered with sand wire netting, clams which ran 3,000 per quart, were obtained by 3 men at the rate of 2 bushels an hour,—an amount sufficient to plant from 1/25 to 1/10 of an acre.
Another problem of importance is the transportation of seed clams, as in many instances the clams will have to be carried some distance. The best method of shipping seed clams is to pack them dry in damp sea weed, putting them in small packages, so they will not be crushed by their own weight. The best though most expensive method is to pack the clams in crates, such as are used for strawberries. It has been found that clams kept in water are not in such good condition as those shipped dry, and it is of the utmost importance that the clams be in good condition when planted.
The length of time a clam will live out of its natural element depends upon the temperature; in cold weather it will keep for several days, and even weeks; while in warm weather the seed clam will be in poor condition after one day's exposure.
Preparing the Grant.—Usually the ground needs no preparation, and the clams can be planted at once. It is a good plan to remove any mussels and any of the enemies of the clam from the grant.
Planting the Clams.—The planting of the seed clams is perhaps the easiest work of the clam culturist, as it necessitates merely the sowing of the seed on the surface of the flat. The small clams when left this way burrow into the ground as soon as the water is over them, and require no planting on the part of the culturist.
Working the Farm.—This style of farming requires no cultivation for the growth of the clams. Once planted, the farmer has no further work until the time when he is ready to dig them. The clams grow better when undisturbed than when the soil is upturned by frequent digging. Protection from man and the natural enemies of the clam demand the attention of the owner at all times.
Harvesting the Clams.—The time of digging will vary as to the size of clam desired and the rate of growth on the grant. The clam farmer can cater to a particular trade by regulating the size of the clams marketed. He may find it more profitable to market a small clam after a short period of growth, or vice versa, on the same principle that a farmer raises hogs for the market.
North of Boston, in localities favorable for fast growth, such as the Essex and Ipswich rivers, by planting large seed of at least l½ inches in the spring, marketable clams of 2½ to 3 inches can be obtained in the fall after six months' growth. Here the clams grow only during the summer months, and nothing would be gained by leaving them over winter. In this way a crop each year can be raised on these farms. In other localities of slower growth it will take from eighteen to twenty-four months to raise a crop. The clam farmer will have to regulate the size of the seed and length of growth to best suit the needs of his farm.