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This paper reports a continuation of trials in which corn is grown in cultivated slits in previously established sods of several single grasses and legumes. An attempt was made to estimate the nitrogen needs of the corn under different intercrops and to determine which intercrops were most adaptable and desirable in this system. Some data on soil moisture under the different systems are reported.With adequate nitrogen, yields of corn in intercrops varied from around 80% of, to approximately the same as, the yields obtained under conventional systems. Among the legumes, Ladino clover and birdsfoot trefoil survived longest as intercrops. While all intercrops competed strongly with the corn for nitrogen, competition by the grasses was most severe and little difference was shown among the grasses with respect to survival and adaptability. Changes in soil moisture were more rapid under intercrop systems because of deeper and more rapid penetration of rainfall and because of utilization of moisture by the intercrop.

T HE relative ability of different corn hybrids to thrive and yield well and to compete with each other at different fertility levels is of agronomic interest. Some hybrids are reputed to yield well under favorable conditions while others are better ab'e to withstand unfavorable conditions and yield relatively better on "poor" soils. Variations in nitrogen content of corn grain and stover also occur. Data reported here bear on this subject although the experiment was set up for another purpose. Materials and MethodsIn 1947 two single-cross hybrids, WFg X Hy and K4 X L31 7, were planted in alternate 40-inch rows in rod-square plots receiving different water and fertility treatments. These fertility treatments were begun the year before this experiment and are given in the footnote to Table 1. Prior to these treatments the plots had been under uniform management in a crop rotation study for several years and were uniform in yielding ability. The soil is a productive brown silt loam that is naturally fertile in potassium and moderately fertile in phosphorus. The plots have all been limed and have pH values of 6~o to 6.5. The plots were in corn in 1946, following oats with sweet and red clover in 1945.Corn was drilled by hand May 10, and the stands were adjusted by thinning to a rate of 15,ooo stalks per acre 2 weeks later. Growing conditions were generally poor during 1947· Total rainfall for July, August, and September was 6.3 inches~about 6o% of the 36-year average-and was poorly distributed. Nearly all the rain from mid-July to mid-September came during the, week of August 20. High temperatures, with daily averages around go°F, prevailed at pollination time.These entire plots were husked by hand by individual rows, and field weights of ear corn were obtained. After a month's storage in a drying shed, the ear corn was weighed again and shelled. The shelled corn was then weighed and run through a mechanical divider to obtain a sample for analysis. Moisture in this grain sample was determined electrometrically, and total nit~ogen was determined by the standard Kjeldahl method.The stover was cut by individual rows at harvest time and weighed immediately to obtain field weights. Several stalks were selected at random and were chopped to obtain the stover sample. These samples were weighed and later dried on a sand bath in the laboratory and reweighed to determine moisture in the field stover. These dried samples were prepared and used for the nitrogen analysis.The Student method for paired data was used in compaying hybrids because the hybrids were grown in alternate rows in the same plot, and the data are suited to this method. This method was also used in comparing fertility treatments. In this case plots were paired when they differed only by the treatment being studied.