28 Richard H. Boerker 
Tas_E oF Sort Moisture CoNTENT IN LicgHT CULTURES IN PER CENT. 
Depth 2 cm. 
Dates | Open Light Medium Shade Dense Shade 
IE /(POSE2s iaawnens create aries meet 12.3 15.3 19.8 
T:2 PBS We vary ater atrace ss eustieae | 12.0 19.0 19.3 
ia ieee O) ie eee ary ne RN oe | 6.1 Te") 18.0 
2 TAT Ol eiaene hesiaie ehascneetemens = 14.0 16.6 BiB 
Bi DATO ce ee ucie dotese 3 estes 14.4 17-0 DIB) 
AY Ate snooty tee 8 gee eee Cie as | 10.3 Tp 19.7 
| 
PANG) fad or eG OTe ILIESS) 16.8 19.9 
Soil depth was comparatively easily controlled, either by only 
partially filling the flats with soil or by using deeper boxes. This 
was done and the depths used were as follows: 
Shallow isomh (occas oe sa pei sleleseuets Cieteeote able eycheceneeetece 4.0 cm. 
IMeditim’ deep ssoil ts ay eee cee ee eer eer eee 9.0 cm. 
Vierya deepcsorl cn. pace peleyneie ta crore vae omen eeaterare eae 30.0 cm. 
The depth of the medium soil was the depth of all the other 
cultures used in the light, soil moisture, and soil texture experi- 
ments. No attempt was made to measure the soil moisture con- 
tent periodically in the soil depth cultures, except as noted in 
checking up the watering of the cultures. 
Soil moisture was controlled in the soil moisture experiment 
by watering the cultures at different intervals. The wet culture 
was watered every evening, the medium wet culture was watered 
every Wednesday noon and Saturday evening and the dry soil 
culture was watered only every Saturday evening. The soil 
samples that were taken were secured just before watering and 
were taken at first every Wednesday noon and every Saturday 
evening and later only every Saturday evening. Thus the soil 
samples represent the minimum water content of the soil at the 
end of one day, at the end of three and one half days, or at the 
end of seven days. In the following table are given the soil 
moisture per cents as taken at various depths according to the 
stage of development of the majority of the seeds or plants in 
the cultures concerned. 
