CONTRIBUTIONS FROM THE WISLEY LABORATORY. 311 



777. Series 2. — Experiments in the Open in ordinary Garden Soil. 

 The plants chosen for this series of experiments were radishes, 

 turnips, and French beans. 



Radishes. — The site of this experiment was the fruit-experiment 

 field. The soil is very sandy, but even in the driest weather, provided 

 it is kept loose at the surface, retains sufficient moisture to keep plants 

 growing and to appear moist at a depth of about three inches. It 

 dries very quickly at the surface, however, so that seeds are apt to lie 

 some time without germinating unless they are watered. Water was 

 therefore applied three or four times until the plants had attained their 

 first rough leaves. 



The ground was divided into three plots, each twelve feet square, 

 called Plot A, Plot B, and Plot C, respectively. 



Plot A was dressed with bacterized peat at the rate of two tons to 

 the acre,* the peat being distributed over the surface and hoed in. 



Plot B received no peat or other manure. 



Plot C received a dressing of untreated peat at the same rate and 

 hoed in in the same way. 



This land had received no manure since 1910, and had been growing 

 plum stocks up to the spring preceding the sowing. The variety of 

 radish called ' French Breakfast ' was sown, twenty grams being sown 

 on each plot. The seed was protected from birds by placing broom 

 branches on the beds, and they were watered at intervals for a few days 

 as noted above. 



The seed was sown on May 20, and the plants were all removed and 

 weighed on July 9. No difference was to be seen in the growth of the 

 plants on the respective plots, nor was there any difference in the rate 

 of germination. 



The following table shows the weights from the several plots: — 





Number of 



Gross weight. 



Average weight. 





Plants. 



Tops. 



Roots. 



Total. 



Tops. 



Roots. 



Total. 



Plot A 



Bacterized peat 

 Plot B 



No dressing . 

 Plot C 



Untreated peat 



276 

 318 



Grms. 

 2590 

 2710 



Grms. 

 3420 

 4220 



Grms. 

 6oiO 

 6930 



; Grms. 

 9-4 

 8-5 



Grms. 

 123 



132 



Grms. 

 21-7 



21-7 



324 



2755 



3875 



6630 



8-5 



1 



12 



20-5 



* Two tons of peat to the acre is, of course, in no way comparable with 

 even the smallest addition of peat used in the flower-pot experiments, viz. one 

 in eight of the compost. To have used it at the same rate would have meant 

 the addition of the treated peat at the rate of about 700 tons to the acre ! This 

 is, of course, altogether out of the bounds of practical horticulture. Prof. 

 Bottomley suggested to us that from 1 ton to 2 tons to the acre would be a 

 sufficient dressing, and in a book published since this Report was in type, and 

 issued with the authority of Prof. Bottomley, a dressing of only £ ton when 

 used outdoors is recommended, presumably as a result of further experience, 

 while 1 part of peat to 10 (or 20 in the case of bulbous plants) of soil is considered 

 the proper quantity for pot plants. 



