Each one of the breeding plot rows should be numbered to correspond with the "register num ber" of the ear from which it is planted, as will be explained under the heading of "Register num ber." The breeding plot should be well protected from foreign pollen, by being planted as far away as possible from other varieties of corn.
Detasseling.
Every alternate row of corn in the breeding plot should be completely detasseled before the pollen matures, and all of the seed corn to be taken from the plot should be selected from these forty-eight detasseled rows. This method absolutely prohibits self-pollination or close-pollination of the future seed. By self-pollination is meant the transfer of pollen from the male flower (tassel) of a given plant to the female flower (silk) of the same plant ; by close-pollination, as here used, is meant the transfer of pollen from the male flower of one plant to the female flower of another plant in the same row, both of which grew from kernels from the same seed ear. It is recommended that no plants in any of the rows which appear im dwarfed, im mature, bar ren or other wise unde sirable, b e allowed to mature pol len. 0 c c a sionally, an entire should be de tasseled be cause of the general infe riority of the row as a whole. These are only pre cautionary measures needing fur ther study, while the value of de tasseling to insure cross-pollination is an established fact. De tasseling is accomplished by going over the rows as many times as may be necessary and carefully pulling out the tassels as they appear. Indeed, great care should be exercised in this part of the work in order not to injure the plants and thereby to lower the yields. The tassels should not be cut off, as this produces an external injury and at the same time the stalk is often deprived of several unde veloped leaves. But the tassel should be allowed to develop far enough so that it can be separated alone at the top joint by a careful pull. It is now determined that the detassel ing of the breeding rows is necessary. This insures cross-pollination and mark edly increases the yield of succeeding crops.
Seleetion of field rows and seed ears.
As the crop matures, the corn from each of the de tasseled breeding rows is harvested. First, all of the ears on the row which appear to be good and which are borne on good plants, in a good position, and with good ear shanks and husks, are harvested, placed in a bag, with the number of the row, and finally weighed, together with the remainder of the crop from the same row. No seed ears should be taken within two or three rods of the inside ends of the rows. The total weight of ear corn which every detasseled row yields should be determined and recorded, for the yield is the primary factor in deter mining the rows from which all of the ears for the next year's seed selection must be taken. Each lot of ears from each of the detasseled rows, and each single ear of the ninety - six ears ultimately selected for seed, is kept labeled with the num ber of the row in which it grew, and finally with its own ear number also, and permanent records are made of the number and the description of the ear, the performance record of the row, and the like, so that, as the breeding is continued, an absolute pedigree is established, on the female side, for every ear of corn which may be produced from this seed so long as the records are made and pre served. It should be the plan to record every fact that bears on the question of efficiency of the plants. We also know absolutely that we have good breeding on the male side, although the exact indi vidual pedigree of the males cannot be known and recorded.
Planting for eross-pollination.
In order to insure cross-breeding to the greatest possible extent, the plan given in Table I should be adopted, varied, perhaps, to meet the necessities of individual cases. The greatest care should be given to the lay-out.
In this plan, the breeding plot is considered by quarters. Each quarter contains twenty-four rows and each row is planted with corn from a separate seed ear. All even-numbered rows are detasseled and seed for the next year's breeding plot is taken from the six best-yielding detasseled rows in each quarter, four ears being taken from each selected row. making ninety-six ears in all.