458 BROOKLYN BOTANIC GARDEN MEMOIRS 
gardeners and foresters have intimated that they have observed indi- 
cations of an accelerated growth in height as a result of coniferous 
seedlings coming in contact with one another. The stimulation effect 
of contact, however, can be observed in the growth of crops and the 
Fic. 2. Showing growth of tomatoes im situ in contact and not in contact with 
one another. 
method of close growing of certain economic plants has its advantages. 
The configuration of plants, however, is greatly modified by close 
growing, as may be observed in the handling of single-stemmed 
chrysanthemums by florists, the growth of corn and various other 
TABLE I 
Showing Growth of Tomatoes (Lycopersicum esculentum Mill.) in Contact and Not tn 
Contact with One Another! 
Average Height and Diameter of Plants (Centimeters) 
| Percentage Gain by Contact 
Height | Diameter ies. * 
Height | Diameter 
Nonialess tannic satiate 19.41 .46 | 
Contact) pescni cise ere ee 47 | 60% | 295 
plants. The stimulative effect of contact of one plant with another 
is shown in Fig. 2. The tomatoes in this case were grown in a well- 
lighted conservatory in soil similar in all respects and the water 
supplied was such that each plant obtained similar amounts. (Cf. 
Table 1.) 
1 36 plants used. 
