In the semi-arid region where crops of grain and also some varieties of field corn can be grown successfully, but where the clovers are not successful; it would seem practicable to sow a few pounds of sweet clover seed per acre at the same time as the grains, and to plow under the plants produced some time in the month of May the next season. The clover thus buried could be at once followed by corn or potatoes, or, indeed, by any kind of a cleaning crop. The high price of seed at present practically forbids growing clover thus. Whether sweet clover grown for renovating uses should be turned under the season in which it has been sown will depend largely on the growth that has been made. In many instances, the growth made is so rank as to justify plowing it under the following autumn. In other instances, better results will follow plowing it under the next season. It frequently happens that the growth made is so rank that a strong plow and also a strong team are necessary to do the work properly. =Value on Alkali soils.=--This plant has been grown to some extent to aid in removing alkali from soils superabundantly impregnated with the same. It will grow, it is claimed, under certain conditions on such soils so surcharged with alkali as to prohibit almost every other form of vegetable growth. The extent to which it may be thus used profitably had not yet been fully demonstrated. But where it can be grown on such soils, the fact that it takes up and removes relatively large quantities of alkali would appear to be well established. =Destroying the Plants.=--Should the conditions be found so favorable to the growth of the plant that it persists in growing where it is not wanted, it will soon cease to appear, if prevented from going to seed. Ordinarily, the blossoms appear only during the second year of growth. If, therefore, the plants are cut off when in bloom, seed forming will not only be prevented, but since sweet clover is a biennial, the plants will die. When thus dealt with, the only source from which other plants may come while extermination is being thus sought is from seed lodged in the soil and still capable of germinating. CHAPTER XII MISCELLANEOUS VARIETIES OF CLOVER