The growing period for an apple tree begins as early as growth starts in the spring and continues up to about midsummer. If cultivation is to stimulate growth as much as possible, it should be done during this period. The first object of cultivation in the early spring is to loosen up, aerate, and dry out the soil, which is usually too wet at that time. As cultivation is continued the soil will become fined and firmed again by the time drier weather comes on. A fairly deep digging and lump crushing tool is the best implement to use up to this time, and a disk or spring-tooth harrow meets these requirements. After this period is passed and during drier weather, cultivation is carried on for a different purpose, namely, to conserve moisture by making a thin dust mulch of soil over the surface. This is best accomplished by shallow-going implements of which the spike-tooth harrow, the acme harrow, or a light wheel cultivator are best. As the season and the amount of rainfall vary, so must tillage operations be varied. In an early dry season begin with the lighter implements earlier. In a late wet season keep the digging tools at work later. As soon as the soil is in good physical condition the principal object of tillage is to modify moisture conditions. As a matter of practice three to four harrowings at intervals of a week to ten days are necessary. Sometimes more, sometimes less are required, according to the character and condition of the soil and the season. The later moisture-conserving tillage should also be carried on every week or ten days, according to weather conditions. It is good practice to stir the soil after every heavy or moderately heavy rain. Use the smoothing tools after light to medium rains and the heavier tools after packing or beating rains. In practice from five to eight or ten of these cultivations are necessary. The drier the season the more necessary does frequent cultivation become. A COVER CROP is so closely associated with tillage that it is usually considered a part of the system. It should be sown in midsummer as soon as tillage ceases. This time will vary from July first to August fifteenth, depending on the locality, the rainfall, the crop of fruit on the trees, and on how favorable the conditions for securing a good stand of the cover crop are. The farther south the locality, or the earlier the fruit, the sooner the crop should be sown. Absence of sufficient rainfall necessitates a continuation of the cultivation, both because it is necessary to conserve all the moisture possible and because it is difficult to get a good stand of a cover crop--especially of one having small seeds--at a dry time in midsummer.