CANE SUGAK. 



In Louisiana, after plant cane and first ratoons have been grown, the land 

 is sown with cow peas ( Vigna unguiculata] , using from one to three bushels per 

 acre ; in August or September the peas are ploughed in and cane planted in 

 October. According to Stubbs, the crop of cow peas above ground is often 

 removed as fodder for cattle, planters who do this holding that the roots supply 

 sufficient nitrogen for the crop, but Stubbs states that when the green crop is 

 ploughed in an average increase over plant and first ratoon cane of 7*42 tons 

 per acre is obtained over that obtained when the green crop is removed for 

 fodder ; the amount of nitrogen afforded by a crop of cow peas is, according to 

 Stubbs, about lOOlbs. per acre. 



In Mauritius there are four crops used as green manures : 



1. The Pois d' Achery (Phaseolm lunatus}. 



2. The Pois Muscat.* 



3. Pigeon Pea (Cajanm indicus}. 



4. Indigo sauvage (Tephrosia Candida}. 



The first two are pea vines growing in dense thick matted masses. The 

 pigeon pea is a shrub growing to a height of four or six feet ; the indigo 

 sauvage is also a shrub, but of rather less robust habit. The system generally 

 followed is to grow cane up to third ratoons ; the land is then planted with one 

 or other of the above crops, the time during which it is rested under the 

 leguminous crop being from one to three years, dependent on the land 

 available. Where land sufficient for one year's rest only is available, the pois 

 muscat is generally grown ; the pois d' Achery is generally allowed to grow for 

 two years, and the pigeon pea and indigo for three or four. All four crops are 

 planted from seed, which is sown about 15 to 18 inches apart. Where no land 

 can be spared to rest, one or other of the above crops is occasionally sown 

 between the rows of cane, and after a few months' growth cut down and 

 buried. 



Although the benefits of green manuring are undoubted, it must be 

 remembered that the expenses connected with it are not small, and very 

 possibly where virgin soil can be had in abundance it may for a time be more 

 economical continually to take in new land than to renew the fertility of old. 

 The benefits of green manuring are most pronounced on estates which have 

 continually to plant on the same soil ; such estates are found in Mauritius, 

 Barbados, and other small islands. 



Besides placing in the soil a supply of readily available nitrogen, green 

 manuring has other advantages. 



* In Sugar and the Sugar Cane I, in error, stated that the Pois Muscat was Mucuna 

 atropurpurea ; the Pois Muscat is, I now find, economically identical with the Velvet Bean of 

 Florida classed as Mucuna puriens var utilis ; the only difference is that the Pois Muscat has 

 a black and the Velvet Bean a mottled seed ; this statement is based on the studies of 

 Bort, in Bull. 141, U.S.D.A. Bureau of Plant Industry, where the Velvet Bean is redescribed as 

 Stizolobium deeringanum.(N .D.) 



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