Importance of Leaf Area in Berry Production 



The total yield of berries in the spring is governed largely by the number of leaves per plant 

 the preceding fall. The following results from controlled leaf area on Fairfax are typical of 

 results on a total of ten varieties in three places and for two years, reported in 19H4 by Darrow 

 (U. S. D. A.) and Beaumont (Md.). 



Leaves f Results in June 1935 >, 



per plant 

 Variety Fall 1934 Leaves Berries Flowers Clusters 



Fairfax 2 — leaves 14.5 12.2 15.5 1.8 



« 4 — " 17.0 3G.3 47.G 4.0 



« 6 — " 31.8 59.0 72.5 4.3 



« 8 — " 25.3 69.7 84.0 5.3 



« 10 — " 32.5 77.3 97.1 7.3 



The larger the number of leaves per plant during the fall, the larger the crop the following 

 spring. Plants in a thickly set matted row with only two or three leaves per plant may be expected 

 to yield only about one-fifth those in spaced rows with ten leaves or more per plant. In these 

 experiments leaves were limited to ten per plant but indications are that with more leaves per 

 plant the crop may be increased in proportion. Fruit bud formation in the strawberry takes 

 place in the fall. It seems likely that the extent of it is determined very largely by leaf area. 

 Fall application of fertilizer, especially nitrogen fertilizers, tends to increase the size and vigor 

 of the plants formed rather than to stimulate runner production. It, therefore, aids in developing 

 a larger leaf area and greater fruit bud formation. All of this seems to indicate that by applying 

 fertilizer in late summer or fall, the effect of nitrogen in increasing total production can be had 

 to a large extent without the softening effect which often comes with the use of lots of nitrogen 

 in spring applications. In practice all of this means select fertile soil, set plants early, give them 

 good cultivation, and use any other means to get the largest number of leaves per plant at the 

 time fruit buds are being formed, which is in the fall except in regions far South. 



Early Rooted Runner Plants Are More Productive 



In Ohio in 1928 yield records were kept of berries from runner plants in twenty-five rows of 

 Premier formed in different months during the season. 



Yield 

 No. of Total per plant 



plants rooted yield in quarts in quarts 



Parent plant 375 48.8 0.13 



Plants rooted in June 162 21.9 0.14 



« " " July 1,989 79.0 0.06 



" " " Aug 3,884 131.1 0.04 



" " « Sept.-Oet. 15 1,127 13.9 0.01 



" " " Oct. 16-Nov 3,375 23.2 0.009 



It will be noted that plants formed in June and July are fifteen times as productive as those 

 made in late October and November. These results check with those made at several other places. 

 If the runner plants had been cut as soon as the new plants were rooted and earlier plants had not 

 helped make and maintain the later ones, the yield differences would probably have been even 

 greater. However, these are sufficient to show the importance of getting good plants, having the 

 ground in good condition and setting the plants out early, so that they can make a good number 

 of early runners which will develop into the most highly productive plants. 



Early runners were saved and carefully spaced. These plants had built up a tremendous leaf area 



by late October. 



15 



